Bug#511603: linux-image-2.6.26-1-amd64: iwl4965 panic
On Mon, Jan 12, 2009 at 12:01:11PM -0600, Michael Ekstrand wrote: > For some time now, I have been experiencing kernel panics (system > frozen, caps lock LED blinking) when using my Intel 4965AGN wireless > card (in a Thinkpad R61). I have only noticed the problems when > connected to my school's WPA-PEAP network. It usually works for some > time and then panics; I am running in X11, so I do not have a dump > available presently. I have no problems when wireless is disabled. > > Based on the timing and the varying natures of networks in which I have > and have not observed the problem, I suspect that it is being triggered > by roaming between access points on the same network. I do not know if > the problem persists or not when using a multi-AP unsecured network. I > have no problems on my home network, which is secured with WPA-PSK and > has a single access point. I am using wpa_supplicant in roaming mode to > manage wireless connectivity. > > I am using firmware from the firmware-iwlwifi package version 0.14. We'll know better when we've got a panic log, but this sounds quite a bit like #502326, which is fixed by a newer firmware image for the 4965 chipset. FWIW, I needed NETCONSOLE and the laptop's wired interface to get the panic log on my machine. After you're able to get a panic log, try installing a new firmware image from http://www.intellinuxwireless.org/?n=downloads&f=ucode and see if it helps. Make sure you reload the module to get the new firmware image loaded (or just reboot). noah signature.asc Description: Digital signature
Bug#511603: linux-image-2.6.26-1-amd64: iwl4965 panic
On Tue, Jan 13, 2009 at 04:24:03PM -0600, Michael Ekstrand wrote: > > I have tried to get a netconsole running, but so far have had no > > success. If I can get a crash with debug=1 this afternoon, I'll post > > any additional info it yields; otherwise, I'll try either the updated > > firmware or the snapshot build and see if I can last tomorrow without > > crashing. > > I have had a crash with debug=1, but it did not have any additional info > in /var/log/messages. That's not surprising. The kernel is likely dead before it gets to write the messages out to the file. You'll really need to set up netconsole... noah signature.asc Description: Digital signature
Bug#502326: Current status?
On Tue, Jan 13, 2009 at 02:03:10PM +0100, Oliver Bock wrote: > I'd like to know the current status of this bug as the root cause got > fixed upstream apparently. Is the fixed microcode already scheduled for > integration into "firmware-iwlwifi" already? The bug still occurs in linux-image-2.6.26-1-686 (2.6.26-13) even with the new firmware. I believe we also need http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.27.y.git;a=commitdiff;h=55d6a3cd0cc85ed90c39cf32e16f622bd003117b;hp=47cbb1107e4172f3632713d74dc8651a32ceb294 though I'm not completely sure why. It seems to me that, if the firmware fixes the problem, the above patch shouldn't be needed. In any case, I'm going to build 2.6.26 with the above patch for testing. If it helps, it'd be really helpful to get it included with an upcoming lenny revision. The lenny kernel is pretty much unusable to me with this bug present... noah signature.asc Description: Digital signature
Bug#505174: linux-image-2.6.26-1-686: After installed vmware-tools, the mouse stuck in debian (i'm running vmware workstation 6.5 in Win XP)
On Wed, Feb 25, 2009 at 11:27:56PM +, Orlando Agostinho wrote: > Package: linux-image-2.6.26-1-686 > Version: 2.6.26-13 > Followup-For: Bug #505174 Why is the is a followup for 505174? It doesn't seem at all related. > > I have vmware workstation 6.5 running in WIN XP. After, installed > debian lenny, the mouse stuck in debian lenny! > I've seen this as well, but since vmware seems to have caused it, and their software is most definitely non-free, I don't think this is a bug in Linux or anything else Debian needs to care about. FWIW, you can work around this by editing your xorg.conf and replacing vmmouse with mouse. noah signature.asc Description: Digital signature
Bug#524373: linux-2.6: /dev/mem rootkit vulnerability
On Thu, Apr 16, 2009 at 11:55:05AM -0400, Michael S. Gilbert wrote: > as seen in recent articles and discussions, the linux kernel is > currently vulnerable to rootkit attacks via the /dev/mem device. one > article [1] mentions that there is an existing patch for the problem, > but does not link to it. perhaps this fix can be found in the kernel > mailing lists. There's no vulnerability there. /dev/mem is only writable by root. The research (if there's really any research involved) just shows how you could hide files or processes by manipulating /dev/mem. That's been known for ages. That's why you don't let your users write to /dev/mem. If the attacker has root, who cares what means they use to hide their precese, you've already lost. noah signature.asc Description: Digital signature
Bug#524373: linux-2.6: /dev/mem rootkit vulnerability
On Thu, Apr 16, 2009 at 04:21:10PM -0400, Michael S. Gilbert wrote: > > i think that any flaw that allows an attacker to elevate his pwnage from > root to hidden should always be considered a grave security issue. Your argument sounds like the one used by RIAA, MPAA etc, based on the DMCA's anti-circumvention clause, to keep things like open source dvd players illegal. Just because something can be used for malicious purposes, doesn't mean its existance is a bad thing. There are reasons for /dev/mem to exist, and why you might want to manipulate kernel state through it. Many of these do not involve rootkits. The support for dynamically loadable kernel modules in Linux can be abuses similarly. Does that make it a "grave security issue"? But as Dann pointed out, we'll have CONFIG_STRICT_DEVMEM in the future to help minimize exposure. If you want to continue this discussion, I propose to do it outside the BTS. noah signature.asc Description: Digital signature
Bug#528504: linux-image-k7: K7 Image not availble
On Wed, May 13, 2009 at 12:35:47PM +0200, Francis Debord wrote: > I got a AMD Geode NX 1700, also know as AMD-AthlonXP-Mobile with > Multiprocessorsupport (an unlocked Athlon / thouroughbred II) on PCCHips > M848A Motherboard. > > When an other sad i686-kernel is working fine and will say i am lying, > he had to come here and bring out the proofs. > > Show me, what you know better than me! Francis, please refer to the following: spider:~$ cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 6 model : 4 model name : AMD Athlon(tm) processor stepping: 2 cpu MHz : 1200.122 cache size : 256 KB fdiv_bug: no hlt_bug : no f00f_bug: no coma_bug: no fpu : yes fpu_exception : yes cpuid level : 1 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr syscall mmxext 3dnowext 3dnow up bogomips: 2403.12 clflush size: 32 power management: spider:~$ uname -r 2.6.26-2-686 spider:~$ uptime 12:16:51 up 19 days, 6:58, 3 users, load average: 0.32, 0.25, 0.17 Uptimes of well over 100 days are common on this system. The 686 kernel fully supports the AMD Athlon process. noah signature.asc Description: Digital signature
Re: Debian Kernel Group Meeting
On Fri, Oct 23, 2009 at 11:06:55AM +0200, Bastian Blank wrote: > > > > xen dom 0 > > > > + > > Are you basing your patch on the PV-ops tree or on one of the SuSE > > forward ports? Based on your recent posts to xen-devel I had assumed the > > former but Ben's initial post suggested perhaps the later. > > It is based on the pv-ops tree. > > Bastian If this is the case, and if we assume that pv-ops xen support is eventually included upstream (which certainly appears to be the goal), why the deprecation notice? noah signature.asc Description: Digital signature
Re: Debian Kernel Group Meeting
On Fri, Oct 23, 2009 at 04:43:31PM +0200, maximilian attems wrote: > > If this is the case, and if we assume that pv-ops xen support is > > eventually included upstream (which certainly appears to be the goal), > > why the deprecation notice? > > who stepped to properly maintain the patch in the current > for the next stable release and more important during it's hole > lifetime!? AIUI, the pv-ops xen support is under active development and will be included in the mainline kernel. There will be no separate patch to maintain. DomU support is already mainline. See http://wiki.xensource.com/xenwiki/XenParavirtOps for details. noah signature.asc Description: Digital signature
Re: Debian Kernel Group Meeting
On Fri, Oct 23, 2009 at 05:08:15PM +0200, maximilian attems wrote: > you still didn't read or get my question: > Who will maintain the chosen pvops patch for the Squeeze lifetime? > > yes, this is the part of the work: > * backward port important fixes, securtiy patches > * read bug reports, decipher oopses and be able to fix them When I hear that this feature will be marked as "deprecated" in squeeze, I interpret that to mean that it is supported, but that it is a legacy feature and will be removed from future versions. In other words, I assume that the kernel team has already decided how things will be handled within squeeze. If this isn't what you mean by "deprecated", could you please clarify what your intentions are, regarding Xen dom0 suppport (pv-ops or otherwise), in squeeze, and in squeeze+1? I don't mean to trivialize the work that must go in to supporting pv-ops/dom0 support in squeeze. If nobody is volunteering to take on this task, I understand that it is a significant issue. I'm just hoping to get a clarification of what the actual situation is. Thanks. noah signature.asc Description: Digital signature
Re: 2.6.29 Kernel, Lenny backports
On Mon, Oct 26, 2009 at 09:04:04PM +, Steve Gane wrote: > I'm trying to use the linux-headers-2.6.29-bpo.2-686 package from > Lenny/backports, but aptitude says it depends on linux-kbuild-2.6.29, > which is not available in Lenny, or Lenny backports, or Squeeze. (This question should have been posted to debian-user or (even better) backports-users, not debian-kernel. (*) This list is used for coordination of development efforts.) I ran into this exact problem today, and took it to mean "You should be using 2.6.30 from backports.org instead". All is now well. noah * http://lists.backports.org/mailman/listinfo/backports-users signature.asc Description: Digital signature
Re: Linux image packages going to depend on python
On Sun, Nov 29, 2009 at 02:15:41PM -0600, Manoj Srivastava wrote: > Perhaps you should consider making the script just create a > ./fstab.new file, and not overwriting /etc/fstab? makes it easier to > test the script out without altering current setup. Keeping a copy of the original file, maybe in /var/backups, might be helpful as well. noah signature.asc Description: Digital signature
Bug#534591: linux-image-2.6.30-1-686: oops when removing i915 kernel module
Package: linux-image-2.6.30-1-686 Version: 2.6.30-1 Severity: normal While trying to debug X issues similar to #524340, I ran "modprobe -r 915", which resulted in the following kernel oops: [ 2417.824670] [drm] Module unloaded [ 2417.872150] BUG: unable to handle kernel NULL pointer dereference at 0010 [ 2417.872408] IP: [] klist_put+0xf/0x58 [ 2417.872590] *pde = [ 2417.872759] Oops: [#1] SMP [ 2417.873006] last sysfs file: /sys/module/video/refcnt [ 2417.873084] Modules linked in: usbhid hid ppdev parport_pc lp parport sco bridge stp bnep rfcomm l2cap bluetooth acpi_cpufreq cpufreq_conservative cpufreq_powersave cpufreq_userspace cpufreq_stats fuse dm_crypt snd_hda_codec_analog snd_hda_intel snd_hda_codec snd_hwdep arc4 ecb evdev serio_raw snd_pcm_oss snd_mixer_oss pcspkr psmouse i2c_i801 snd_pcm uvcvideo i2c_core videodev v4l1_compat iwlagn iwlcore mac80211 snd_seq_midi snd_rawmidi thinkpad_acpi cfg80211 rfkill snd_seq_midi_event battery led_class snd_seq nvram ac snd_timer snd_seq_device snd soundcore snd_page_alloc processor button ext3 jbd mbcache dm_mirror dm_region_hash dm_log dm_snapshot dm_mod sd_mod crc_t10dif ide_pci_generic uhci_hcd ata_generic ahci libata video(-) output ehci_hcd intel_agp agpgart piix scsi_mod ide_core e1000e usbcore thermal fan thermal_sys [last unloaded: i2c_algo_bit] [ 2417.876102] [ 2417.876102] Pid: 9065, comm: modprobe Not tainted (2.6.30-1-686 #1) 64781TU [ 2417.876102] EIP: 0060:[] EFLAGS: 00010246 CPU: 0 [ 2417.876102] EIP is at klist_put+0xf/0x58 [ 2417.876102] EAX: EBX: 0001 ECX: 0002 EDX: 0001 [ 2417.876102] ESI: EDI: f6455d78 EBP: 0080 ESP: f43f3f10 [ 2417.876102] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 2417.876102] Process modprobe (pid: 9065, ti=f43f2000 task=f7398550 task.ti=f43f2000) [ 2417.876102] Stack: [ 2417.876102] 0002 c03fccb8 0080 c030fd5f c040bd14 c040bd14 f6455d78 [ 2417.876102] f7398550 f822441c c026c291 f82244dc 093b9be0 f8220029 [ 2417.876102] c0145a54 65646976 c017006f f6bdd3c8 0246 f6bdd3c8 b7f28000 [ 2417.876102] Call Trace: [ 2417.876102] [] ? klist_remove+0x51/0x7a [ 2417.876102] [] ? bus_remove_driver+0x59/0x88 [ 2417.876102] [] ? cleanup_module+0xa/0x1a [video] [ 2417.876102] [] ? sys_delete_module+0x18e/0x1e7 [ 2417.876102] [] ? wb_timer_fn+0xf/0x27 [ 2417.876102] [] ? remove_vma+0x3e/0x43 [ 2417.876102] [] ? do_munmap+0x20e/0x228 [ 2417.876102] [] ? sysenter_do_call+0x12/0x28 [ 2417.876102] Code: 39 d3 75 e4 8b 06 fe 00 85 ed 74 08 85 ff 74 04 89 f8 ff d5 8b 46 04 5b 5e 5f 5d c3 55 57 89 c7 56 53 8b 30 89 d3 83 e6 fe 89 f0 <8b> 6e 10 e8 c7 e4 00 00 84 db 74 17 f6 07 01 74 0f ba 45 00 00 [ 2417.876102] EIP: [] klist_put+0xf/0x58 SS:ESP 0068:f43f3f10 [ 2417.876102] CR2: 0010 [ 2417.889612] ---[ end trace d76f27590b9dc7de ]--- -- Package-specific info: ** Version: Linux version 2.6.30-1-686 (Debian 2.6.30-1) (wa...@debian.org) (gcc version 4.3.3 (Debian 4.3.3-11) ) #1 SMP Sun Jun 14 16:11:32 UTC 2009 ** Command line: BOOT_IMAGE=/boot/vmlinuz-2.6.30-1-686 root=UUID=3308441b-88a7-45e3-84dd-9181366a0f1b ro quiet ** Tainted: G D (128) ** Kernel log: [ 14.283501] iwlagn :03:00.0: firmware: requesting iwlwifi-4965-2.ucode [ 14.343159] iwlagn :03:00.0: loaded firmware version 228.57.2.23 [ 14.545521] Registered led device: iwl-phy0::radio [ 14.545553] Registered led device: iwl-phy0::assoc [ 14.545577] Registered led device: iwl-phy0::RX [ 14.545600] Registered led device: iwl-phy0::TX [ 14.613964] ADDRCONF(NETDEV_UP): wlan0: link is not ready [ 16.403385] wlan0: authenticate with AP 00:22:6b:54:61:da [ 16.405475] wlan0: authenticated [ 16.405480] wlan0: associate with AP 00:22:6b:54:61:da [ 16.407676] wlan0: RX AssocResp from 00:22:6b:54:61:da (capab=0x401 status=0 aid=1) [ 16.407680] wlan0: associated [ 16.424259] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready [ 16.424626] wlan0: disassociating by local choice (reason=3) [ 27.056088] wlan0: no IPv6 routers present [ 74.397065] usb 5-1: new low speed USB device using uhci_hcd and address 2 [ 74.573135] usb 5-1: New USB device found, idVendor=046d, idProduct=c00e [ 74.573140] usb 5-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 74.573145] usb 5-1: Product: USB-PS/2 Optical Mouse [ 74.573148] usb 5-1: Manufacturer: Logitech [ 74.573273] usb 5-1: configuration #1 chosen from 1 choice [ 74.620014] usbcore: registered new interface driver hiddev [ 74.633498] input: Logitech USB-PS/2 Optical Mouse as /devices/pci:00/:00:1d.0/usb5/5-1/5-1:1.0/input/input10 [ 74.633628] generic-usb 0003:046D:C00E.0001: input,hidraw0: USB HID v1.10 Mouse [Logitech USB-PS/2 Optical Mouse] on usb-:00:1d.0-1/input0 [ 74.633650] usbcore: registered new interface driver usbhid [ 74.633654] usbhid: v2.6:USB HID core driver [ 80.324475] nepomukservices[3725]: segfault at 4 ip
Bug#542470: closed by maximilian attems (Re: Bug#542470: linux-image-2.6.30-1-686: IPv6 can not be disabled)
On Thu, Aug 20, 2009 at 10:47:56PM +0200, advocatux wrote: > Yep, I know I can add "ipv6.disable=1" in /boot/grub/menu.lst but this > method doesn't work always, it depends on which 2.6.30 kernel version > you're running. So this bug was closed when 2.6.30 was uploaded to unstable, no? We're not going to support anything less than 2.6.30 with the squeeze release. Are you claiming that something needs to be done in lenny and/or etch? It doesn't seem like it. noah signature.asc Description: Digital signature
Bug#502326: linux-image-2.6.26-1-686: crash in iwl3945
Package: linux-image-2.6.26-1-686 Version: 2.6.26-8 Severity: important My thinkpad X300 has recently developed a rather unpleasant case of instability related to the iwl3945 driver. This bug may be identical to #500914, though the symptoms, including stack trace, are slightly different. Unlike #500914, there's no reason to think that this bug is related to proximity to the access point, as mine is pretty much right outside my door. Also, the crash doesn't happen on boot, but usually happens within about 30 minutes or so. lspci -v reports this wireless interface as 03:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN Network Connection (rev 61) Subsystem: Intel Corporation Lenovo ThinkPad T51 Flags: fast devsel, IRQ 17 Memory at f9f0 (64-bit, non-prefetchable) [size=8K] Capabilities: Kernel driver in use: iwl4965 Kernel modules: iwl4965 Kernel output follows: [ 878.071717] iwl4965: Error wrong command queue 63 command id 0x0 [ 878.071717] [ cut here ] [ 878.071717] kernel BUG at drivers/net/wireless/iwlwifi/iwl4965-base.c:3465! [ 878.071717] invalid opcode: [#1] SMP [ 878.071717] Modules linked in: i915 drm rfcomm l2cap bluetooth uinput ppdev parport_pc lp parport ipv6 acpi_cpufreq cpufreq_powersave cpufreq_stats cpufreq_userspace cpufreq_conservative cpufreq_ondemand freq_table netconsole configfs fuse loop joydev snd_hda_intel snd_seq_dummy snd_pcm_oss snd_mixer_oss snd_seq_oss arc4 snd_seq_midi snd_rawmidi snd_pcm ecb crypto_blkcipher psmouse serio_raw snd_seq_midi_event pcspkr i2c_i801 i2c_core iTCO_wdt snd_seq iwl4965 firmware_class iwlcore rfkill mac80211 cfg80211 snd_timer snd_seq_device snd soundcore snd_page_alloc ac battery bay video output button intel_agp agpgart evdev thinkpad_acpi led_class nvram ext3 jbd mbcache ide_cd_mod cdrom sd_mod piix ide_pci_generic ide_core ahci ata_generic libata scsi_mod dock ehci_hcd uhci_hcd usbcore e1000e thermal processor fan thermal_sys [ 878.071717] [ 878.071717] Pid: 0, comm: swapper Not tainted (2.6.26-1-686 #1) [ 878.071717] EIP: 0060:[] EFLAGS: 00010092 CPU: 1 [ 878.071717] EIP is at iwl4965_irq_tasklet+0x2db/0x4de [iwl4965] [ 878.071717] EAX: 0047 EBX: f16b4000 ECX: EDX: 0092 [ 878.071717] ESI: 0001 EDI: f7599020 EBP: f759a058 ESP: f7493ec8 [ 878.071717] DS: 007b ES: 007b FS: 00d8 GS: SS: 0068 [ 878.071717] Process swapper (pid: 0, ti=f7492000 task=f748f520 task.ti=f7492000) [ 878.071717] Stack: 4001 0282 c010fca5 316b4000 0008 005b 005c [ 878.071717]f7599aa0 0006d38c 8000 f759f110 000a 0001 [ 878.071717]c0126867 0001 c036da68 c0126419 0046 c0372de0 00da [ 878.071717] Call Trace: [ 878.071717] [] lapic_next_event+0xc/0x10 [ 878.071717] [] tasklet_action+0x68/0xd0 [ 878.071717] [] __do_softirq+0x66/0xd3 [ 878.071717] [] do_softirq+0x45/0x53 [ 878.071717] [] irq_exit+0x35/0x67 [ 878.071717] [] do_IRQ+0x52/0x63 [ 878.071717] [] common_interrupt+0x23/0x28 [ 878.071717] [] module_param_sysfs_remove+0xf/0x23 [ 878.071717] [] acpi_idle_enter_bm+0x2a9/0x317 [processor] [ 878.071717] [] cpuidle_idle_call+0x5b/0x86 [ 878.071717] [] cpuidle_idle_call+0x0/0x86 [ 878.071717] [] cpu_idle+0xab/0xcb [ 878.071717] === [ 878.071717] Code: 8b 88 a8 00 00 00 66 8b 41 06 0f b6 d4 81 e2 bf 00 00 00 83 fa 04 74 17 0f b6 41 04 50 52 68 df 2d ae f8 e8 f0 95 64 c7 83 c4 0c <0f> 0b eb fe 0f b6 d0 f6 c4 40 89 54 24 28 8b 87 b0 23 00 00 75 [ 878.071717] EIP: [] iwl4965_irq_tasklet+0x2db/0x4de [iwl4965] SS:ESP 0068:f7493ec8 [ 878.071717] Kernel panic - not syncing: Fatal exception in interrupt -- Package-specific info: ** Version: Linux version 2.6.26-1-686 (Debian 2.6.26-8) ([EMAIL PROTECTED]) (gcc version 4.1.3 20080623 (prerelease) (Debian 4.1.2-23)) #1 SMP Thu Oct 9 15:18:09 UTC 2008 ** Command line: root=/dev/sda1 ro quiet vga=791 quiet ** Not tainted ** Kernel log: [7.526021] Registered led device: tpacpi::dock_batt [7.526021] Registered led device: tpacpi::unknown_led [7.526021] Registered led device: tpacpi::standby [7.529644] thinkpad_acpi: Lenovo BIOS switched to ACPI backlight control mode [7.529644] thinkpad_acpi: standard ACPI backlight interface available, not loading native one... [7.529644] input: ThinkPad Extra Buttons as /class/input/input1 [7.862017] input: Power Button (FF) as /class/input/input2 [7.908595] Linux agpgart interface v0.103 [7.910076] ACPI: Power Button (FF) [PWRF] [7.910163] input: Lid Switch as /class/input/input3 [7.937991] agpgart: Detected an Intel 965GM Chipset. [7.937991] agpgart: Detected 7676K stolen memory. [7.942542] ACPI: Lid Switch [LID] [7.942626] input: Sleep Button (CM) as /class/input/input4 [7.953152] agpgart: AGP aperture is 256M @ 0xe000 [8.01
Bug#502326: Acknowledgement (linux-image-2.6.26-1-686: crash in iwl3945)
And of course, the bug report should have mentioned iwl4965, not 3945. Retitled accordingly. noah signature.asc Description: Digital signature
Bug#502326: Acknowledgement (linux-image-2.6.26-1-686: crash in iwl4965)
Instability has gotten bad enough that I'm trying a homegrown 2.6.27.3 image. Uptime is approaching 20 hours, all with wireless active, and no sign of trouble, but it's way too soon to tell if it really made a difference... noah signature.asc Description: Digital signature
Bug#502326: Acknowledgement (linux-image-2.6.26-1-686: crash in iwl4965)
I've now confirmed that this crash will happen with 2.6.27.3 as well. :( I'll see about pursuing this with upstream. signature.asc Description: Digital signature
Bug#502326: upstream bug assigned
tags 502326 + upstream thanks This is bug http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1703 signature.asc Description: Digital signature
Bug#502326: firmware update
On Sat, Nov 29, 2008 at 01:57:12AM +0100, Moritz Muehlenhoff wrote: > > I can also confirm (2) that given the provided firmware by Zhu Yi the > > issue is fixed on the same 2.6.27.7 kernel I built and talked about > > before (1) for Lenny, using the iwl4965 driver. > > > > 1: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=502326#41 > > 2: http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1703#c53 > > Did anyone test, whether Zhu Yi's firmware also fixes this issue > with the standard Lenny kernel? I cannot confirm that it actually fixes anything with the current lenny kernels, because I've not been experiencing this bug recently. It seems to have something to do with the wireless network environment (number of wireless clients, a misbehaving client, or something along those lines) and the particular issues haven't come up recently. I can, however, confirm that the new firmware doesn't actually seem to *break* anything in lenny. noah signature.asc Description: Digital signature
Bug#1061445: linux-image-6.7-cloud-amd64: Built CONFIG_VIRTIO_BLK into kernel
On Wed, Apr 03, 2024 at 06:26:46PM +0200, Paul Menzel wrote: > Sorry, I have the feeling we talk past each other. I do not want to create > an initrd. I want to boot *without* an initrd, and the only missing piece is > building VIRTIO_BLK into the Linux kernel. > > Ubuntu also builds this into their “kvm” flavour [1]. > > If you think, that is unnecessary, could you please elaborate, how I would > achieve the goal with virtiofs? The cloud kernel generally targets VM guests on the Microsoft Azure and Amazon EC2 cloud environments, neither of which benefit from VIRTIO_BLK driver being statically linked as you describe. I think that's the primary reason for reluctance to make your requested change. For background, the Azure and AWS clouds present well-defined device models, making it straightforward for us to construct targeted kernel configs for them. noah
Re: ocfs2_dlmfs missing from the cloud kernel
On Fri, May 17, 2024 at 05:34:57PM +0200, Bastian Blank wrote: > > > how do I change this? > > You install the non-cloud kernel. > > The cloud kernel is limited in scope. And the decision was that not > everything you can do on platforms is in scope. To clarify the scope a bit, historically the cloud kernels have specifically targeted Amazon EC2 and Microsoft Azure. The rationale for this is that these providers present a consistent and reasonably well defined device model, meaning we can be sure what drivers and other kernel features are needed and which we can leave out. It is not intended to be usable on every cloud service. The module in question, ocfs2_dlmfs, is not, to my knowledge, generally useful in the cloud environments targeted by the cloud kernel. If we had the resources, it'd be great provide further optimized kernel builds, e.g. one for EC2 specifically, Azure specifically, GCP, and maybe some sort of OpenStack/QEMU VM definition. Unfortunately, we do not currently have those resources. So, IMO, a wishlist bug against src:linux asking for another build configuration would be a reasonable way to record an interest in such a change. The kernel team may be able to provide more context on which specific resources would be needed in order to support this. Maybe in the future it'll get implemented. noah
Re: Kernel features and Cloud (and GCE)
On Mon, May 27, 2024 at 03:37:08PM +0200, Emanuele Rocca wrote: > > So we have the problem that the Debian cloud kernel supports some, but > > not all, of the devices our shared users need, and we’re not sure of > > the right way to solve that. We wondered if we should switch the > > images to the generic kernel, or if there’s a way we could help the > > cloud kernel support more clouds, or if there’s a better solution we > > haven’t thought of. > > I think the best approach is enabling the needed modules one by one in > the cloud image following the procedure above. Andrew's question is a bit higher level than that, and mostly boils down to "Which cloud environments do we actually want to support with the cloud kernel?" We have declined requests to enable modules in the cloud kernel in the past, referring people to the standard kernel instead (see e.g. #969140). See also the previous discussion at #https://lists.debian.org/debian-kernel/2020/04/msg6.html We have not, as far as I can recall, ever explicitly stated a policy around this, nor have we documented what it would take for us to support more fine-grained kernel builds (i.e. what stops us from generating a kernel image targeting *only* GCP). noah
Re: Closing of buster-backports?
On Wed, Sep 07, 2022 at 07:37:45AM +0200, Alexander Wirt wrote: > > > Now that buster is LTS and no longer officially supported, should the > > > -backports pocket be closed? AFAIK, buster just receives the security > > > uploads by the -security pocket and shouldn't have -backports open > > > anymore. I hope I am not mistaken or missing anything? > > > > > > FTR, packages are still entering the -backports pocket and this > > > probably needs to stop(!?) > > > > Why should it stop? If people are willing to do the work to backport a > > package, why should it be blocked? The understanding is that the release as > > a whole will not be supported, but voluntary updates will continue. > > we (backports ftpmasters) asked that question some time ago. Consensus was > that the backports > maintainers doesn't want to support oldstable backports over its lts > lifetime. > > For that reason we will close oldstable-backports soon. The cloud team publishes images for various cloud environments (OpenStack, Amazon EC2, etc). The primary (and most popular, from the data I have) images use the main kernel, but we publish alternative images that boot the backports kernel by default. Is there a plan to continue offering new kernels for buster LTS? If we simply close the backports archive, we leave these users without a path forward without upgrading to bullseye, which is something they're evidently not ready for. We can cease publication of these images, which will limit new adoption, but it'd be nice to continue providing at least kernel backports. noah
Bug#890343: linux: make fq_codel default for default_qdisc
On Fri, Feb 26, 2021 at 06:58:50PM +0100, Vincent Blut wrote: > > > I think the distinction is that the other packages that tweak sysctl > > > values don't claim to be doing so on behalf of the kernel team. If > > > the > > > kernel team is responsible for the values being set, then the > > > settings > > > should come from a package that the kernel team owns, not some other > > > package. > > > > Right, maybe in linux-base? Although that might annoy derivatives that > > want different defaults. > > > > procps is the wrong place, not just because it's out of our hands, but > > because systemd applies sysctl configuration now and procps is > > optional. > > Is there a definitive answer from the kernel team about how this should be > implemented? In the meantime, Noah sent [1]. I've rebased https://salsa.debian.org/kernel-team/linux/-/merge_requests/309 against the current 'master' kernel branch on Salsa. Basic test results are below. It'd be nice if the kernel team could have a look and give feedback on the approach or recommend an alternative one if this isn't the one they'd like to pursue. # before reboot: admin@ip-10-0-0-136:~$ /sbin/tc qdisc qdisc noqueue 0: dev lo root refcnt 2 qdisc mq 0: dev ens5 root qdisc pfifo_fast 0: dev ens5 parent :2 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1 qdisc pfifo_fast 0: dev ens5 parent :1 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1 admin@ip-10-0-0-136:~$ sudo apt install ./linux-image-5.16.0-rc3-cloud-amd64-unsigned_5.16~rc3-1~exp2_amd64.deb Reading package lists... Done Building dependency tree... Done Reading state information... Done Note, selecting 'linux-image-5.16.0-rc3-cloud-amd64-unsigned' instead of './linux-image-5.16.0-rc3-cloud-amd64-unsigned_5.16~rc3-1~exp2_amd64.deb' The following additional packages will be installed: firmware-linux-free Suggested packages: linux-doc-5.16 debian-kernel-handbook grub-pc | grub-efi-amd64 | extlinux The following NEW packages will be installed: firmware-linux-free linux-image-5.16.0-rc3-cloud-amd64-unsigned ... admin@ip-10-0-0-136:~$ sudo reboot Connection to 18.236.97.48 closed by remote host. ... admin@ip-10-0-0-136:~$ uname -a Linux ip-10-0-0-136 5.16.0-rc3-cloud-amd64 #1 SMP PREEMPT Debian 5.16~rc3-1~exp2 (2021-12-01) x86_64 GNU/Linux admin@ip-10-0-0-136:~$ /sbin/tc qdisc qdisc noqueue 0: dev lo root refcnt 2 qdisc mq 0: dev ens5 root qdisc fq_codel 0: dev ens5 parent :2 limit 10240p flows 1024 quantum 1514 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64 qdisc fq_codel 0: dev ens5 parent :1 limit 10240p flows 1024 quantum 1514 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64
Re: Bug#1006346: cloud.debian.org: bullseye AMIs don't boot on Amazon EC2 Xen instances with Enhanced Networking
Control: reassign -1 src:linux Control: tags -1 + upstream > Amazon EC2 instance types with Enhanced Networking use the ixgbevf.ko > driver. The current AMIs successfully probe the ixgbevf driver and spawn > dhclient as expected, but dhclient appears to never receive a lease. Older > AMIs do work on this class of instance. Upstream commit 83dbf898a2d4 "PCI/MSI: Mask MSI-X vectors only on success" seems to introduce a regression that breaks the "Enhanced Networking" feature used on Amazon EC2 instances, which use PCI passthrough access to Intel ethernet devices using the ixgbevf.ko driver. Systems using this hardware seem to probe their network hardware as usual, and don't log any errors to the console, but are never able to communicate over the NIC. Device details: 00:03.0 Ethernet controller: Intel Corporation 82599 Ethernet Controller Virtual Function (rev 01) Physical Slot: 3 Flags: bus master, fast devsel, latency 64 Memory at f300 (64-bit, prefetchable) [size=16K] Memory at f3004000 (64-bit, prefetchable) [size=16K] Capabilities: Kernel driver in use: ixgbevf Kernel modules: ixgbevf The issue is present in Debian kernels in sid and experimental. The patch has been backported to stable branches including those used in our stable releaseѕ: The 5.10.x (released with v5.10.88) is e5949933f313. Since bullseye is currently using v5.10.92, it is impacted. The 4.19.x branch (released with v4.19.222) is 12ae8cd1c7e9. Since buster is still on v4.19.208, it is not yet impacted, but likely would be with the next kernel update. This issue has been reported elsewhere as well, for example Fedora CoreOS at https://github.com/coreos/fedora-coreos-tracker/issues/1066 I have confirmed that reverting e5949933f313 from 5.10.x results in a build that functions properly with this hardware on bullseye, but this is probably not a reasonable thing to do generally. noah
Bug#1007144: linux-image-cloud-amd64: Network doesn't come up on AWS Xen-based EC2 instances (ex c4.large)
Control: reassign -1 src:linux Control: forcemerge 1006346 -1 On Sat, Mar 12, 2022 at 01:21:23AM +, Reilly Brogan wrote: > I bisected this issue and it was introduced in kernel 5.10.88 as commit > e5949933f313c9e2c30ba05b977a047148b5e38c "PCI/MSI: Mask MSI-X vectors > only on success", thus present in linux-image-5.10.0-11-amd64 which uses > the 5.10.92 kernel (and all newer versions of the package). I've already reported this as https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1006346 The change implicated has been backported to all the upstream stable branches, so this basically impacts all the current Debian kernels (or will, once they're updated).
Bug#1006346: cloud.debian.org: bullseye AMIs don't boot on Amazon EC2 Xen instances with Enhanced Networking
>From the upstream discussion on the linux-pci mailing list [*]: > Yes. My understanding is that the issue is because AWS is using older > versions of Xen. They are in the process of updating their fleet to a > newer version of Xen so the change introduced with Stefan's commit > isn't an issue any longer. > > I think the changes are scheduled to be completed in the next 10-12 > weeks. For now we are carrying a revert in the Fedora Kernel. > > You can follow this Fedora CoreOS issue if you'd like to know more > about when the change lands in their backend. We work closely with one > of their partner engineers and he keeps us updated. > https://github.com/coreos/fedora-coreos-tracker/issues/1066 Ideally we can revert the upstream commit from the stable kernels, since otherwise Debian users on AWS Xen instance types may be stuck using older, unsafe kernels. Especially if we have time to include the change in the upcoming bullseye and buster point releases. If the kernel updates for those stable updates have already been built, though, it might be too late to matter. By the time we publish our next kernel builds, the AWS Xen update may be complete. noah * https://lore.kernel.org/linux-pci/c4a65b9a-d1e2-bf0d-2519-aac718593...@redhat.com/
Bug#1006346: cloud.debian.org: bullseye AMIs don't boot on Amazon EC2 Xen instances with Enhanced Networking
On Sat, Mar 19, 2022 at 10:41:39AM +0100, Salvatore Bonaccorso wrote: > > >From the upstream discussion on the linux-pci mailing list [*]: > > > > > Yes. My understanding is that the issue is because AWS is using older > > > versions of Xen. They are in the process of updating their fleet to a > > > newer version of Xen so the change introduced with Stefan's commit > > > isn't an issue any longer. > > > > > > I think the changes are scheduled to be completed in the next 10-12 > > > weeks. For now we are carrying a revert in the Fedora Kernel. > > > > > > You can follow this Fedora CoreOS issue if you'd like to know more > > > about when the change lands in their backend. We work closely with one > > > of their partner engineers and he keeps us updated. > > > https://github.com/coreos/fedora-coreos-tracker/issues/1066 > > > > Ideally we can revert the upstream commit from the stable kernels, since > > otherwise Debian users on AWS Xen instance types may be stuck using > > older, unsafe kernels. Especially if we have time to include the change > > in the upcoming bullseye and buster point releases. If the kernel > > updates for those stable updates have already been built, though, it > > might be too late to matter. By the time we publish our next kernel > > builds, the AWS Xen update may be complete. > > Wehere one can track the update status for their Xen version directly > or is following the above the only reference? It's just for reference; the deployment timeline isn't published. As far as I know, it's also subject to change in the event that unexpected issues arise or it's preempted by some high severity issue. > How frequent is this particular combination of hardware/software? We > have the change already applied for a while in bullseye, buster would > be impacted new since the last update done for security fixes The impacted instance types aren't the most common, as they're not the latest generation. So I expect that the majority of the impact is felt by people or organizations that haven't yet been able to make time to switch to newer instance types. The implication here, of course, is that many of these deployments may be production environment where stability is prioritized over migration to the new thing. We get a little bit of data about what instance types are used with Debian on AWS, but it's incomplete as it only reflects usage by AWS customers who use access Debian via the AWS Marketplace. Consider it something like popcon data; it's essentially opt-in. If the data we get from the Marketplace covering the past 3 days worth of activity is representative of the Debian usage in general, then it looks like roughly 1% of Debian users on AWS are trying to use the impacted instance types. > Are there workarounds for the affected users of this combination? I > see some options listed in > https://wiki.debian.org/Cloud/AmazonEC2Image/Bullseye People can use newer generation instance types, which are not impacted. Depending on the use case, that could be a trivial change, but it could also be disruptive. Newer instance types aren't based on Xen at all and expose a different hardware device model to the instance. Debian supports the newer instance types, but the end user workload may still need additional nontrivial qualification. > If we revert the commit it reverts a fix for a bug with Marvell NVME > devices. > > But we cannot just revert the commit for the cloud images. Understood. > If we know something about the release schedule from Amazon to update > their Xen instances (which is the way to move forward, since upstream > won't revert the commit) then we should leave the status as it is for > bullseye (and now for buster). For bullseye there is there is > CVE-2022-0847 fixes they would need to pick up. Yes, the problem will go away when the Xen fleet is updated. It sounds like we're looking at roughly a 3 month timeline, after which point the patch won't be a problem. However, until then, people who need to use Xen instances will be stuck either running an unsafe kernel or building their own. noah
Re: Generating a cloud / VM kernel package
On Sat, Aug 26, 2017 at 05:18:45PM +0100, Ben Hutchings wrote: > > Thomas, can you elaborate why you think this a good idea? Is this about > > boot time of the kernel image? The thing I really do not want to have is > > additional kernel source uploads to the archive for just those cloud > > kernel images, but you already considered that a bad idea (from what I > > read between your lines). > > When the Google Cloud people talked to me about slow booting, it turned > out that reconfiguring initramfs-tools to MODULES=dep made a big > improvement. That is likely to be a sensible configuration for most > cloud images. I'm not sure that'll work for us. The image generation is not generally expected to occur on cloud instances (though in practice it certainly may). OTOH, the list of required modules may be small enough for us to enumerate the ones we need for booting in /etc/initramfs-tools/modules. I will look into this, and we'll see what it does to boot times. noah signature.asc Description: PGP signature
Re: Generating a cloud / VM kernel package
On Mon, Aug 28, 2017 at 01:31:31AM +0100, Ben Hutchings wrote: > > OTOH, the list of required modules may be small enough for us to > > enumerate the ones we need for booting in /etc/initramfs-tools/modules. > > ...and then you could use MODULES=list. initramfs-tools will still > follow module static dependencies in this case. > > > I will look into this, and we'll see what it does to boot times. > > Note that the saving will mainly be in time to load the initramfs - > which on Google Compute Engine is done through BIOS disk services that > have very low performance. The mere presence of the unneeded modules > in the initramfs won't cause them to be loaded into the kernel and > shouldn't make much difference to the time taken to boot after this > point. On Amazon's HVM instance families, the initramfs is read from "local" disk, which may be network-attached or actually local. I haven't profiled load times in great depth, but my guess is that reading and uncompressing the image would be the biggest contributors to the load time. In my experimentation, uncompressing an 18 MB initramfs takes roughly 500 ms of clock time when read from network storage. That's not completely insignificant, but considering the fragility of MODULES=list or MODULES=dep, I'm not sure it's the best place to look for optimizations right now. noah signature.asc Description: PGP signature
Re: Generating a cloud / VM kernel package
On Sun, Aug 27, 2017 at 04:16:50PM +0200, Thomas Goirand wrote: > Basically, the only thing that I want to see is a specific config for > that kernel, nothing else. Otherwise, it's going to be too much > maintenance work. Indeed, it should *not* be a different source upload, > that's too much work as well. There also may be some optimization that > we could do. > > Also, I don't see this happening without a prior agreement from the > kernel team (which means probably that Ben has to agree). On our side, > we could prepare a list of kernel modules that we do *not* want. You might consider looking at what Ubuntu did to their kernel. https://insights.ubuntu.com/2017/04/05/ubuntu-on-aws-gets-serious-performance-boost-with-aws-tuned-kernel/ suggests that they did more than just disable some modules, but it's light on details. If we're able to come up with a specific list of proposed changes, we'll probably be able to have a more fruitful conversation. noah signature.asc Description: PGP signature
Bug#910049: linux-image-4.18.0-1-cloud-amd64: Please enable Amazon ENA NIC support
Package: linux-image-4.18.0-1-cloud-amd64 Version: 4.18.8-1 Severity: wishlist Tags: patch Control: affects -1 cloud.debian.org The cloud variant of the kernel packages does not currently enable CONFIG_ENA_ETHERNET, meaning it is not able to drive the network hardware on modern AWS instances. A patch for enabling this is attached. I have tested it with the linux sources from stretch-backports on an AWS m5d instance and confirmed that the ENA driver is properly enabled and functional. --- /mnt/config.amd64_none_cloud-amd64 2018-10-01 20:47:28.803906526 + +++ .config 2018-10-01 20:58:42.155319362 + @@ -4,7 +4,7 @@ # # -# Compiler: gcc-6 (Debian 6.3.0-18+deb9u1) 6.3.0 20170516 +# Compiler: gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516 # CONFIG_64BIT=y CONFIG_X86_64=y @@ -57,6 +57,7 @@ # CONFIG_COMPILE_TEST is not set CONFIG_LOCALVERSION="" # CONFIG_LOCALVERSION_AUTO is not set +CONFIG_BUILD_SALT="" CONFIG_HAVE_KERNEL_GZIP=y CONFIG_HAVE_KERNEL_BZIP2=y CONFIG_HAVE_KERNEL_LZMA=y @@ -1935,7 +1936,8 @@ # CONFIG_NET_VENDOR_ALACRITECH is not set # CONFIG_NET_VENDOR_ALTEON is not set # CONFIG_ALTERA_TSE is not set -# CONFIG_NET_VENDOR_AMAZON is not set +CONFIG_NET_VENDOR_AMAZON=y +CONFIG_ENA_ETHERNET=m # CONFIG_NET_VENDOR_AMD is not set # CONFIG_NET_VENDOR_AQUANTIA is not set # CONFIG_NET_VENDOR_ARC is not set
Bug#910049: Acknowledgement (linux-image-4.18.0-1-cloud-amd64: Please enable Amazon ENA NIC support)
Submitted the patch in more complete form at https://salsa.debian.org/kernel-team/linux/merge_requests/68
Bug#896165: linux: request packaging of bpftool
On Fri, Apr 20, 2018 at 02:07:40PM +0200, Simon Horman wrote: > I would like to request packaging of bpftool which has been > included in upstream Linux tree since v4.15-rc1. I expect this can > be done in a similar manner to the way that perf, also present in > the upstream Linux kernel tree, is packaged. I've started some work on this. It's not ready to be merged with the kernel packaging but does build. Please see https://salsa.debian.org/noahm/linux/commits/bpftool and feel free to send improvements. noah signature.asc Description: PGP signature
Bug#896165: linux: request packaging of bpftool
On Fri, Apr 20, 2018 at 02:07:40PM +0200, Simon Horman wrote: > I would like to request packaging of bpftool which has been > included in upstream Linux tree since v4.15-rc1. I expect this can > be done in a similar manner to the way that perf, also present in > the upstream Linux kernel tree, is packaged. Please see https://salsa.debian.org/kernel-team/linux/merge_requests/72 It's not ready for merge, but hopefully it gets some good feedback and I can get it ready before long. I expect that applying the same patch to the 4.18 branch for sid will be straightforward. Is the plan for buster to include 4.18, or 4.19? Or something else? noah signature.asc Description: PGP signature
Bug#896165: linux: request packaging of bpftool
On Mon, Nov 19, 2018 at 11:34:26PM -0800, Noah Meyerhans wrote: > Please see https://salsa.debian.org/kernel-team/linux/merge_requests/72 Ugh. We cannot currently package bpftool in Debian. There are several GPLv2-only files in its source tree, and it links unconditionally against the GPLv3 libbfd. :( There is work underway to make libbfd optional, so the situation may change before too long: https://www.mail-archive.com/netdev@vger.kernel.org/msg254808.html noah signature.asc Description: PGP signature
Bug#896165: linux: request packaging of bpftool
On Tue, Nov 27, 2018 at 09:50:17AM -0800, Jakub Kicinski wrote: > > > Please see https://salsa.debian.org/kernel-team/linux/merge_requests/72 > > > > Ugh. We cannot currently package bpftool in Debian. There are several > > GPLv2-only files in its source tree, and it links unconditionally > > against the GPLv3 libbfd. :( > > If we relicense the GPLv2-only files to be GPLv2-only OR BSD-2-Clause > - like the majority of bpftool sources - would that work? > > I wanted to make sure GPLv2-only + BSD-2-Clause will satisfy the > license requirement when linking against libbfd, before I start chasing > people for acks on the relicense :) Yes, the BSD 2-clause license is OK. GPLv2 or greater would be OK, too. It's really just GPLv2-only in this case that's causing the problem. noah signature.asc Description: PGP signature
Bug#915229: src:linux: Updated driver needed for Amazon ENA ethernet
Package: src:linux Severity: important ENA is an ethernet adaptor used on Amazon EC2 cloud instances. Version 2.0.2 of the ENA driver was added to the mainline kernel as of version 4.20. This version includes fixes for various bugs, some of which result in kernel panics, and is needed in order to enable access to features available on newer hardware. It is also needed in order to support the recently announced arm64-based instances. I have opened https://salsa.debian.org/kernel-team/linux/merge_requests/77 to backport ENA 2.0.2 to 4.19 for buster. I have a WIP branch for stretch's 4.9 kernel at https://salsa.debian.org/noahm/linux/tree/stretch+ena2 This requires a bit more effort as 4.9 contains a much older version of the driver. Thanks noah
Bug#915231: src:linux: Enable PCI_HOTPLUG for arm64
Package: src:linux Version: 4.9.130-2 Severity: wishlist Tags: stretch Amazon recently announced arm64-based EC2 instances. These instances rely on PCI_HOTPLUG functionality to support attach/detach of resources such as ethernet interfaces and block devices. PCI_HOTPLUG is enabled for arm64 in buster and sid, but not stretch. Please enable PCI_HOTPLUG for arm64 in order to support EC2 on arm64. Thanks noah
Bug#915231: Proposed fix submitted on salsa
Control: tags -1 + patch Merge request: https://salsa.debian.org/kernel-team/linux/merge_requests/80
Bug#915229: src:linux: Updated driver needed for Amazon ENA ethernet
Control: tags -1 + patch Merge request for Linux 4.9 (stretch): https://salsa.debian.org/kernel-team/linux/merge_requests/81
Bug#918188: linux: FTBFS on arm64
On Fri, Jan 04, 2019 at 06:57:21AM +0100, Salvatore Bonaccorso wrote: > > LD vmlinux.o > > MODPOST vmlinux.o > > GEN .version > > CHK include/generated/compile.h > > UPD include/generated/compile.h > > CC init/version.o > > LD init/built-in.o > > ./drivers/firmware/efi/libstub/lib.a(arm64-stub.stub.o): In function > > `handle_kernel_image': > > ./debian/build/build_arm64_none_arm64/./drivers/firmware/efi/libstub/arm64-stub.c:63: > > undefined reference to `__efistub__GLOBAL_OFFSET_TABLE_' > > ld: ./drivers/firmware/efi/libstub/lib.a(arm64-stub.stub.o): relocation > > R_AARCH64_ADR_PREL_PG_HI21 against external symbol > > `__efistub__GLOBAL_OFFSET_TABLE_' can not be used when making a shared > > object; recompile with -fPIC > > /<>/Makefile:1010: recipe for target 'vmlinux' failed > > make[5]: *** [vmlinux] Error 1 > > Makefile:152: recipe for target 'sub-make' failed > > make[4]: *** [sub-make] Error 2 > > Makefile:24: recipe for target '__sub-make' failed > > make[3]: *** [__sub-make] Error 2 > > make[3]: Leaving directory > > '/<>/debian/build/build_arm64_none_arm64' > > debian/rules.real:190: recipe for target > > 'debian/stamps/build_arm64_none_arm64' failed > > make[2]: *** [debian/stamps/build_arm64_none_arm64] Error 2 > > make[2]: Leaving directory '/<>' > > debian/rules.gen:400: recipe for target 'build-arch_arm64_none_arm64_real' > > failed > > make[1]: *** [build-arch_arm64_none_arm64_real] Error 2 > > make[1]: Leaving directory '/<>' > > debian/rules:41: recipe for target 'build-arch' failed > > make: *** [build-arch] Error 2 > > dpkg-buildpackage: error: debian/rules build-arch gave error exit status 2 > > https://buildd.debian.org/status/fetch.php?pkg=linux&arch=arm64&ver=4.9.144-1&stamp=1546572157&raw=0 The problem was introduced with upstream commit 27b5ebf61818749b3568354c64a8ec2d9cd5ecca. Reverting that commit fixes the build, but there may be a better option. signature.asc Description: PGP signature
Re: Possibilities for a special Azure or cloud Linux package
On Fri, Dec 15, 2017 at 08:03:51PM +0100, Bastian Blank wrote: > > > We at credativ are responsible for maintaining the Azure cloud images. > > > We got asked by Microsoft to explore the possibilities of introducing a > > > specialised Linux image for this plattform into Debian. The main > > > enhancements we look at would be: > > > - faster boot of the instance, > > > - smaller memory footprint of the running kernel, and > > > - new features. > > > > However, if it is possible to create a single flavour that provides > > those sorts of enhancements for multiple cloud platforms, I think that > > would be worthwhile. > > I have some initial findings for a kernel using a derived config. I > reduced the boot time by 5 seconds (from 30 to 25). The installed size > was reduced from 190 to 50MB. > > Microsoft published a patch set against 4.13 and 4.14 > https://github.com/Microsoft/azure-linux-kernel > they would like to add. > > Now the question is if other cloud providers would like to follow such a > path by using and careing for a specialised linux image for this > platforms? I'd be interested in helping to support work for a cloud kernel and verifying its functionality on EC2. I can't, however, make a lot of promises about how much time I can commit to this effort. In our previous thread on this topic[1] it was suggested[2] that a tuned initramfs config might go a long way toward reducing boot times. It's not an investigation to which I've been able to devote much time, unfortunately, but I think we should pursue that path to completion before we look at patching the kernel or providing custom builds. Has this been done on any cloud platform yet? noah 1. https://lists.debian.org/debian-cloud/2017/08/msg00025.html 2. https://lists.debian.org/debian-cloud/2017/08/msg00032.html signature.asc Description: PGP signature
Bug#969140: linux-image-5.7.0-0.bpo.2-amd64: Please enable CONFIG_F2FS_FS in the cloud image kernel
On Sat, Aug 29, 2020 at 11:43:21AM +1000, Hamish Moffatt wrote: > > > Could you please enable CONFIG_F2FS_FS in the cloud kernel? > > [...] > > > > What makes you think f2fs will be commonly used in cloud deployments? > > > I don't know that it will be, but as it supports encryption and compression > and benchmarks shows it performs at least as well as ext4, I don't see why > it couldn't be a good choice for virtual machines. It seems at least as > useful in a cloud deployment as minix and hpfs which are included in this > flavour. This sounds like a good argument for turning off minix and hpfs to me. ;) Is F2FS usable as a Debian root filesystem? Does it support all the features (file capabilities and POSIX ACLs, for example) that are commonly used on Debian systems? The cloud team, for what it's worth, does not have any plans to switch from ext4 in the forseeable future. (We probably would not do so unless Debian made the change distro-wide.) That doesn't mean we shouldn't consider enabling it, but I'd like to see a clearer use case. My small amount of research into it (mostly reading wikipedia and a couple of the reference sources) suggests that it's most popular on phones and similar devices, not cloud instances. Do you see use cases involving manipulating filesystems for those type of devices in cloud VMs? Or something else? How are crypto keys handled for its encryption functionality? The cloud kernel is not expected to be useful for 100% of people, even in cloud environments. In cases where specific functionality is needed that isn't available in the cloud kernel, the generic kernel is available and I'd probably recommend that. noah
Bug#969443: src:linux: none
Package: src:linux Version: 4.19.132-1 Severity: important Tags: buster When used in virtual machine environments, Linux on amd64 is able to report "steal time" to the guest. This functionality has been supported by Linux on amd64 for years, but was only added to arm64 with Linux 5.5. As Debian and arm64 are increasingly used in virtual environments, including cloud environments, the ability to report steal time is increasingly important for system monitoring and performance analysis. Thus, I'd like to request that CPU steal time accounting support for arm64 be backported to buster, if possible. noah
Bug#969443: arm64: please backport stolen time support to buster kernel (Re: src:linux: none)
On Wed, Sep 02, 2020 at 06:09:46PM -0700, Jonathan Nieder wrote: > > Subject: src:linux: none > > It looks like you forgot to include a subject line? *sigh* Computers are hard. > The relevant series is a4b28f5c6798 (Merge remote-tracking branch > 'kvmarm/kvm-arm64/stolen-time' into kvmarm-master/next, 2019-10-24). > It may be possible to try applying it if you are interested. That is the series I had in mind, yes. I will open a merge request once I have one prepared and tested. > That said, for this kind of issue that is about new features instead > of hardware support, my advice would be to use a more current kernel > from backports instead. That's not an option for users requiring security support. While the prevelance of arm64-based clouds is still relatively low, it is growing. As it becomes more common, the lack of visibility into CPU steal time will become a significant issue for people running in these environments, hence the "important" severity. noah
Bug#969443: Info received (Bug#969443: arm64: please backport stolen time support to buster kernel (Re: src:linux: none))
Control: tags -1 + patch I've submitted a merge request containing a proposed fix at https://salsa.debian.org/kernel-team/linux/-/merge_requests/268 Tested in an arm64 KVM environment with steal time reporting; validated its behavior against that of the sid kernel.
Bug#972709: Wishlist/RFC: Change to CONFIG_PREEMPT_NONE in linux-image-cloud-*
On Sun, Nov 22, 2020 at 03:53:32PM -0800, Flavio Veloso Soares wrote: > Unfortunately, I couldn't find many comprehensive benchmarks of kernel > CONFIG_PREEMPT* options. The one at > > [1]https://www.codeblueprint.co.uk/2019/12/23/linux-preemption-latency-throughput.html > seems to be very thorough, > > [...] > > Not particularly. I'm used to latency benchmarks showing e.g. average, > 90th percentile, 99th percentile, as well as worst. I don't think Ben was talking about specific benchmarks. The web page you cites lacks basic measurements one would expect to see from *any* meaningful performance benchmark. Comparing maximum latency is fine, but it's not really relevant by itself. If a configuration change improves the worst case (100th percentile) but negatively impacts the 50th percentile, is that a change worth making? Maybe. But without having that data at all, the benchmark really isn't worth much at all. It's totally reasonable for us to consider making this change, but we should have comprehensive data about the impact of doing so. What impact does the change have on different classes of workloads? e.g. high tps, CPU-bound, IO-bound, etc. It's entirely possible that the proposed change improves performance under certain workloads, but negatively impacts others. Without knowing the impact in more in more detail, which would allow us to evaluate the tradeoffs, I don't think there's a compelling reason to make a change. noah
Bug#977005: cloud: Additional modules to disable
Package: src:linux Version: 5.9.11-1 Severity: wishlist Per discussion in the recent cloud-team meeting, there are several additional modules that can be disabled in the cloud kernel. The proposed candidates for removal is below; please feel free to critique specific entries if you think there's a need to leave them enabled. fs/coda/coda.ko (CODA_FS) fs/reiserfs/reiserfs.ko (REISERFS_FS) fs/hpfs/hpfs.ko (HPFS_FS) fs/hfsplus/hfsplus.ko (HFSPLUS_FS) fs/hfs/hfs.ko (HFS_FS) fs/jfs/jfs.ko (JFS_FS) fs/nilfs2/nilfs2.ko (NILFS2_FS) fs/minix/minix.ko (MINIX_FS) fs/ecryptfs/ecryptfs.ko (ECRYPT_FS) Thanks noah
Bug#977615: arm64: memory corruption bug
Package: src:linux Version: 4.19.160-2 Severity: important Tags: upstream fixed-upstream Control: fixed -1 5.9.15-1 Control: fixed -1 5.10~rc7-1~exp1 Control: found -1 5.9.11-1 Opening a bug for visibility. Arguably this could be Severity: grave given that memory corruption can lead to data loss. It has been fixed upstream in 4.19.161, 5.9.12, and 5.10. I'm not sure about the status for 4.9/stretch LTS. There is a memory corruption bug impacting arm64. The upstream fix was made in 5.10 with commit ff1712f953e2 ("arm64: pgtable: Ensure dirty bit is preserved across pte_wrprotect()"). The upstream commit [1] describes the issue as: With hardware dirty bit management, calling pte_wrprotect() on a writable, dirty PTE will lose the dirty state and return a read-only, clean entry. Impact from the issue has been observed in the real world on systems running redis, as described at https://github.com/redis/redis/issues/8124 (note in particular comments [2] and [3], where the kernel connection is made). 1. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ff1712f953e27f0b0718762ec17d0adb15c9fd0b 2. https://github.com/redis/redis/issues/8124#issuecomment-745791340 3. https://github.com/redis/redis/issues/8124#issuecomment-745838911
Bug#977615: arm64: memory corruption bug
> Thanks. Pending currently with the ongoing rebase in the v4.19.y > series in > https://salsa.debian.org/kernel-team/linux/-/merge_requests/295 . > > Just we need to check if this warrants a regression update issued > earlier via stable-updates. If possible, I'd vote for an release via stable-updates, and I'd be happy to put together a merge request for such a release. It seems that the bug is triggered during relatively uncommon circumstances (CoW and MADVISE_FREE used together), but in places where it is triggered, the impact is severe and there is no practical workaround. noah
Bug#890343: linux: make fq_codel default for default_qdisc
On Thu, Apr 23, 2020 at 03:34:06PM -0700, Matt Taggart wrote: > #890343 was originally opened against systemd asking to install the upstream > systemd sysctl.d/50-default.conf file that sets: > > net.core.default_qdisc = fq_codel > > As explained in #950701 (and the systemd debian changelog) the debian > systemd maintainers felt that systemd in debian should not be changing > kernel policies (and I agree). > So #890343 was reassigned to linux to consider changing the default. > > fq_codel is better in every way than pfifo_fast and I am unaware of any > reason why it would not be a better default. (but don't trust me, ask the > kernel networking experts) > > Can we change it? I strongly agree that we should make this change for the bullseye release. I'm looking into provding a patch to implement the switch to fq_codel by default, but it appears to require something more than just a kernel config change. I have tried the following with the 5.10 kernel from the current sid branch: CONFIG_NET_SCH_FQ_CODEL=m CONFIG_DEFAULT_FQ_CODEL=y CONFIG_DEFAULT_NET_SCH="fq_codel" Then we don't see any change at all to the qdisc in use: admin@ip-10-0-0-162:~$ grep -i fq_codel /boot/config-$(uname -r) CONFIG_NET_SCH_FQ_CODEL=m CONFIG_DEFAULT_FQ_CODEL=y CONFIG_DEFAULT_NET_SCH="fq_codel" admin@ip-10-0-0-162:~$ /sbin/sysctl net.core.default_qdisc net.core.default_qdisc = pfifo_fast admin@ip-10-0-0-162:~$ tc qdisc show dev ens5 qdisc mq 0: root qdisc pfifo_fast 0: parent :2 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1 qdisc pfifo_fast 0: parent :1 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1 admin@ip-10-0-0-162:~$ ip link show dev ens5 2: ens5: mtu 9001 qdisc mq state UP mode DEFAULT group default qlen 1000 link/ether 02:47:e2:7c:be:ff brd ff:ff:ff:ff:ff:ff altname enp0s5 If we statically link the fq_codel module into the kernel, then we see: admin@ip-10-0-0-162:~$ grep -i fq_codel /boot/config-$(uname -r) CONFIG_NET_SCH_FQ_CODEL=y CONFIG_DEFAULT_FQ_CODEL=y CONFIG_DEFAULT_NET_SCH="fq_codel" admin@ip-10-0-0-162:~$ /sbin/sysctl net.core.default_qdisc net.core.default_qdisc = fq_codel admin@ip-10-0-0-162:~$ /sbin/tc qdisc show dev ens5 qdisc mq 0: root qdisc fq_codel 0: parent :2 limit 10240p flows 1024 quantum 1514 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64 qdisc fq_codel 0: parent :1 limit 10240p flows 1024 quantum 1514 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64 admin@ip-10-0-0-162:~$ ip link show dev ens5 2: ens5: mtu 9001 qdisc mq state UP mode DEFAULT group default qlen 1000 link/ether 02:47:e2:7c:be:ff brd ff:ff:ff:ff:ff:ff altname enp0s5 So in this case, we have fq_codel configured, but not as the root qdisc for the interface. If we manually set it: admin@ip-10-0-0-162:~$ sudo /sbin/tc qdisc add root dev ens5 fq_codel Then we get the following configuration: admin@ip-10-0-0-162:~$ /sbin/tc qdisc show dev ens5 qdisc fq_codel 8001: root refcnt 3 limit 10240p flows 1024 quantum 9015 target 5ms interval 100ms memory_limit 32Mb ecn drop_batch 64 admin@ip-10-0-0-162:~$ ip link show dev ens5 2: ens5: mtu 9001 qdisc fq_codel state UP mode DEFAULT group default qlen 1000 link/ether 02:47:e2:7c:be:ff brd ff:ff:ff:ff:ff:ff altname enp0s5 I believe that this is what we want. Is that accurate? The recent thread at https://www.mail-archive.com/netdev@vger.kernel.org/msg380410.html also seems relevant. noah
Bug#890343: linux: make fq_codel default for default_qdisc
On Sun, Jan 17, 2021 at 10:29:44PM -0300, Ivan Baldo wrote: > I think we want the mq qdisc to distribute the load between cores, to > support very high speed network cards or too slow CPUs. Yep, you're right. Though it's not about CPU cores, but about tx queues on the NIC hardware. > Also, if net.core.default_qdisc = fq_codel is used, it also has the mq > qdisc and fq_codel childs for each CPU core, so that's the default behavior > in other distros. Yep, so I think the behavior when we set the default qdisc to fq_codel in the kernel config has the effect we're looking for, after all. noah
Bug#890343: linux: make fq_codel default for default_qdisc
On Wed, Jan 20, 2021 at 10:22:16PM +0100, Vincent Blut wrote: > My proposal would differ from yours though in that it would not touch the > kernel > configuration but would instead consist in patching procps to provide a > configuration file (let's say default_qdisc.conf) to set the value of the > net.core.default_qdisc variable to fq_codel via sysctl. > This would allow to benefit from FQ_Codel without depending on a specific > Linux > version. We could do that. However, in the past (earlier in this bug, even) it's been pointed out that other packages should not be responsible for setting kernel policies, so changes like this should be the responsibility of the kernel packages. That seems like a sensible position to take. One possible way for the kernel team to take ownership of this would be for it to introduce a new "debian-kernel-sysctl" package or something like that to provide some sysctl.d drop-in files. It could then set net.core.default_qdisc, and potentially others in various scenarios. Such a package can be installed indepdendently of whether the user is running a Debian-provided kernel package. The other alternative is the one I've proposed, which involves changing the compile-time defaults in Debian's kernel packages. This obviously only affects users of those packages. However, I think that's fine; people who are building their own packages may very well be starting from Debian's config, in which case they'll still get this change, or may be constructing their own configuration from scratch, in which case they're assuming ownership of all the parameters. noah
Bug#890343: linux: make fq_codel default for default_qdisc
Control: tags -1 + patch A proposed patch is at https://salsa.debian.org/kernel-team/linux/-/merge_requests/309
Bug#890343: linux: make fq_codel default for default_qdisc
On Wed, Jan 20, 2021 at 11:39:16PM +0100, Vincent Blut wrote: > > We could do that. However, in the past (earlier in this bug, even) it's > > been pointed out that other packages should not be responsible for > > setting kernel policies, so changes like this should be the > > responsibility of the kernel packages. That seems like a sensible > > position to take. > > If this is the position of the kernel team, then fine. But some packages *do* > tweak kernel parameters using the sysctl interface mechanism. So does the > kernel > team provides documention about what is acceptable? I think the distinction is that the other packages that tweak sysctl values don't claim to be doing so on behalf of the kernel team. If the kernel team is responsible for the values being set, then the settings should come from a package that the kernel team owns, not some other package. AFAIK, there are no guidelines or policy anywhere in Debian about whether or not a package can provide its own sysctl settings. noah
Bug#809293: linux-image-3.16.0-4-amd64: network regression in 3.16.7-ckt20-1+deb8u1 breaks ipv6 ike/ipsec negotiations
Package: src:linux Version: 3.16.7-ckt20-1+deb8u1 Severity: normal Following the recent kernel security update, racoon(8) from ipsec-tools can no longer negotiate an IPSec security association with an ipv6 peer. IPv4 does not appear affected. Racoon logs the following: Dec 28 13:20:42 amarth racoon: ERROR: recvmsg (Resource temporarily unavailable) Dec 28 13:20:42 amarth racoon: ERROR: failed to receive isakmp packet at isakmp.c:238: Resource temporarily unavailable This happens when trying to read an IKE (udp port 500) message from the peer. Downgrading to 3.16.7-ckt11-1+deb8u3 resolves the problem. My first guess was that it was related to the recently added net-add-validation-for-the-socket-syscall-protocol.patch fix, so I tried backing that out, but it didn't help. Then I realized that there were a lot more changes between 3.16.7-ckt11-1+deb8u3 and 3.16.7-ckt20-1+deb8u1 than what were described in the DSA. I'm attempting to identify the specific commit (at least to the debian packaging repo, if not the actual ckt kernel) Thanks Noah -- Package-specific info: ** Version: Linux version 3.16.0-4-amd64 (debian-kernel@lists.debian.org) (gcc version 4.8.4 (Debian 4.8.4-1) ) #1 SMP Debian 3.16.7-ckt20-1+deb8u1 (2015-12-14) ** Command line: BOOT_IMAGE=/vmlinuz-3.16.0-4-amd64 root=/dev/mapper/amarth--vg-root ro include console=tty1 console=ttyS0,115200 ** Not tainted ** Kernel log: [7.248625] systemd[1]: Starting Syslog Socket. [7.264080] systemd[1]: Listening on Syslog Socket. [7.269054] systemd[1]: Starting Journal Service... [7.292065] systemd[1]: Started Journal Service. [7.537734] systemd-udevd[205]: starting version 215 [7.922679] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input4 [7.930230] ACPI: Power Button [PWRF] [8.020609] shpchp: Standard Hot Plug PCI Controller Driver version: 0.4 [8.041411] ipmi message handler version 39.2 [8.093982] intel_rng: FWH not detected [8.098337] IPMI System Interface driver. [8.102708] ipmi_si: probing via SMBIOS [8.106607] ipmi_si: SMBIOS: io 0xca8 regsize 1 spacing 4 irq 0 [8.112626] ipmi_si: Adding SMBIOS-specified kcs state machine [8.118574] ipmi_si: Trying SMBIOS-specified kcs state machine at i/o address 0xca8, slave address 0x20, irq 0 [8.152503] input: PC Speaker as /devices/platform/pcspkr/input/input6 [8.177073] EDAC MC: Ver: 3.0.0 [8.192219] EDAC MC0: Giving out device to module i5000_edac.c controller I5000: DEV :00:10.0 (POLLED) [8.201979] EDAC PCI0: Giving out device to module i5000_edac controller EDAC PCI controller: DEV :00:10.0 (POLLED) [8.313606] [drm] Initialized drm 1.1.0 20060810 [8.328595] dcdbas dcdbas: Dell Systems Management Base Driver (version 5.6.0-3.2) [8.364313] ipmi_si ipmi_si.0: Found new BMC (man_id: 0x0002a2, prod_id: 0x0100, dev_id: 0x20) [8.373025] ipmi_si ipmi_si.0: IPMI kcs interface initialized [8.414596] iTCO_vendor_support: vendor-support=0 [8.419814] iTCO_wdt: Intel TCO WatchDog Timer Driver v1.11 [8.425511] iTCO_wdt: Found a 631xESB/632xESB TCO device (Version=2, TCOBASE=0x0860) [8.433453] iTCO_wdt: initialized. heartbeat=30 sec (nowayout=0) [8.613050] [drm] radeon kernel modesetting enabled. [8.618713] [drm] initializing kernel modesetting (RV100 0x1002:0x515E 0x1028:0x01B2). [8.626780] [drm] register mmio base: 0xFC2D [8.631475] [drm] register mmio size: 65536 [8.635822] radeon :0e:0d.0: VRAM: 128M 0xD800 - 0xDFFF (16M used) [8.644525] radeon :0e:0d.0: GTT: 512M 0xB800 - 0xD7FF [8.652220] [drm] Detected VRAM RAM=128M, BAR=128M [8.657090] [drm] RAM width 16bits DDR [8.660836] [TTM] Zone kernel: Available graphics memory: 1026588 kiB [8.667472] [TTM] Initializing pool allocator [8.673206] [TTM] Initializing DMA pool allocator [8.679313] [drm] radeon: 16M of VRAM memory ready [8.685456] [drm] radeon: 512M of GTT memory ready. [8.693034] [drm] GART: num cpu pages 131072, num gpu pages 131072 [8.720561] [drm] PCI GART of 512M enabled (table at 0x7A60). [8.727459] radeon :0e:0d.0: WB disabled [8.731806] radeon :0e:0d.0: fence driver on ring 0 use gpu addr 0xb800 and cpu addr 0x88007921 [8.742676] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013). [8.749358] [drm] Driver supports precise vblank timestamp query. [8.755595] [drm] radeon: irq initialized. [8.759790] [drm] Loading R100 Microcode [8.759855] ipmi device interface [8.776300] radeon :0e:0d.0: firmware: direct-loading firmware radeon/R100_cp.bin [8.784408] [drm] radeon: ring at 0xB8001000 [8.789518] [drm] ring test succeeded in 1 usecs [8.794319] [drm] ib test succeeded in 0 usecs [8.799096] [drm] Radeon Display Connectors [8.803346] [drm] Connector 0: [8.806463] [drm] VGA-1 [8
Bug#809293: linux-image-3.16.0-4-amd64: network regression in 3.16.7-ckt20-1+deb8u1 breaks ipv6 ike/ipsec negotiations
On Mon, Dec 28, 2015 at 03:22:52PM -0800, Noah Meyerhans wrote: > Following the recent kernel security update, racoon(8) from ipsec-tools > can no longer negotiate an IPSec security association with an ipv6 peer. > IPv4 does not appear affected. > > Racoon logs the following: > Dec 28 13:20:42 amarth racoon: ERROR: recvmsg (Resource temporarily > unavailable) > Dec 28 13:20:42 amarth racoon: ERROR: failed to receive isakmp packet at > isakmp.c:238: Resource temporarily unavailable > > This happens when trying to read an IKE (udp port 500) message from the > peer. > > Downgrading to 3.16.7-ckt11-1+deb8u3 resolves the problem. git-bisect of the debian packaging repo suggests that the problem was introduced in 3.16.7-ckt17. Looking at the git logs for that release, the only commit that is obviously related to ipv6 and udp is f3106f: Author: Eric Dumazet Date: Tue Jul 14 08:10:22 2015 +0200 ipv6: lock socket in ip6_datagram_connect() commit 03645a11a570d52e70631838cb786eb4253eb463 upstream. ip6_datagram_connect() is doing a lot of socket changes without socket being locked. This looks wrong, at least for udp_lib_rehash() which could corrupt lists because of concurrent udp_sk(sk)->udp_portaddr_hash accesses. But I haven't tested anything yet... noah
Bug#809293: linux-image-3.16.0-4-amd64: network regression in 3.16.7-ckt20-1+deb8u1 breaks ipv6 ike/ipsec negotiations
On Tue, Dec 29, 2015 at 11:39:46AM -0800, Noah Meyerhans wrote: > > Dec 28 13:20:42 amarth racoon: ERROR: recvmsg (Resource temporarily > > unavailable) > > Dec 28 13:20:42 amarth racoon: ERROR: failed to receive isakmp packet at > > isakmp.c:238: Resource temporarily unavailable > > > > This happens when trying to read an IKE (udp port 500) message from the > > peer. > > > > Downgrading to 3.16.7-ckt11-1+deb8u3 resolves the problem. > > git-bisect of the debian packaging repo suggests that the problem was > introduced in 3.16.7-ckt17. Bisecting the upstream kernel changes suggests the following commit as being the origin of the problem: commit bd0900e5eed6502b314402d36ec11f6d1a67de82 Author: Herbert Xu Date: Mon Jul 13 20:01:42 2015 +0800 net: Fix skb csum races when peeking commit 89c22d8c3b278212eef6a8cc66b570bc840a6f5a upstream. When we calculate the checksum on the recv path, we store the result in the skb as an optimisation in case we need the checksum again down the line. This is in fact bogus for the MSG_PEEK case as this is done without any locking. So multiple threads can peek and then store the result to the same skb, potentially resulting in bogus skb states. This patch fixes this by only storing the result if the skb is not shared. This preserves the optimisations for the few cases where it can be done safely due to locking or other reasons, e.g., SIOCINQ. Signed-off-by: Herbert Xu Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Luis Henriques I will confirm this by trying a build with this change reverted, and will also check to see if there have been followup changes upstream of the ckt kernels that might have corrected the problem. noah
Bug#952108: Cloud variant: please enable CONFIG_VHOST_SCSI
On Sun, Feb 23, 2020 at 12:28:53AM -0800, Josh Triplett wrote: > The normal Debian kernel configuration has CONFIG_VHOST_SCSI enabled, > but the cloud configuration does not seem to have it enabled. Please > enable CONFIG_VHOST_SCSI=m on the cloud configuration as well. Out of curiosity, where is this actually needed?
Re: virtio_mmio.device parameter unknown as kernel config option is disabled
On Thu, Mar 05, 2020 at 10:31:37PM +0100, João Mikos wrote: > I am experimenting with running a Debian Buster microVM under the > Firecracker hypervisor, using a stock Debian kernel (converted to > vmlinux format) and an initrd.img file. When booting the microVM with > this setup, I receive the following error message inside the microVM, > which halts booting: Hi João. I have extensive experience with Firecracker, with both Debian and other distros as the guest OS. In general, the expectation with Firecracker is that it will not work with distro kernels out-of-the-box, but that it requires a custom kernel specifically configured for MicroVM deployments. Keep in mind that Firecracker originally didn't even provide initramfs support, meaning that all device and filesystem drivers needed to be statically linked into the kernel. Although Firecracker has since added initramfs support, its goal of minimal feature sets and extremely fast boot times still encourages you to use a customized kernel. > I could trace this to the flag CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES > being disabled in the default Debian kernel config. ... > 1) Is there any specific reason for this flag to be disabled in the > Debian kernel? It's not generally useful, so it hasn't been deemed appropriate for inclusion in the standard kernel builds. It'll be up to the kernel team to decide if supporting Firecracker with the default kernel is a sufficiently interesting use-case to warrant changing it. IMO, it is not. > 2) If the flag is disabled for no specific reason, is there any chance > for this flag to be enabled in future Debian versions, so the > virtio_mmio module recognizes the .device parameter by default? You should open a wishlist severity bug against the src:linux package to officially request this change. noah
Re: virtio_mmio.device parameter unknown as kernel config option is disabled
On Fri, Mar 06, 2020 at 09:44:26AM +0100, João Mikos wrote: > Reflecting about what you said the default kernel might indeed not be > the best place to enable this, but maybe the cloud kernel could be a > good candidate instead. Official support for Firecracker might be a > stretch, especially due to the goals you've mentioned, but I am seeing > projects (e.g. Ignite) using Firecracker as a basis. Any such derived > project would be benefited by this change. But indeed, the kernel team > has the best view on whether they want to support (with all that > entails) any new flag or feature. On the contrary, tools that integrate Firecracker directly, like Ignite, Kata Containers, and firecracker-containerd, are the ones that will benefit the most from using a custom kernel. Indeed, all of those projects provide their own kernel images for use with Firecracker. These kernel images are configured to omit drivers for devices that are not present in Firecracker's device model, some of of which lead to long delays in the boot process while they probe for nonexistent devices. Support for Firecracker in the default Debian kernel could be interesting for experimentation, but I think you'd want to switch to a customized kernel as soon as possible before running in production. Given that the kernel in a Firecracker MicroVM is loaded by the host, rather than being embedded in the guest VM image, I think a kernel supporting Firecracker might be better handled in a manner similar to the user-mode-linux kernel package. https://packages.debian.org/buster/user-mode-linux That would be a package that'd be installed on the system hosting MicroVMs, where it could provide an uncompressed kernel image for use by Firecracker. noah
Bug#955366: Enable CONFIG_KSM in the cloud kernel
Package: src:linux Version: 4.19.98-1 Severity: wishlist Owner: no...@debian.org Relaying a request on behalf of an Amazon EC2 customer. The generic kernel enables CONFIG_KSM, but the cloud kernel disables this. The customer makes extensive use of KSM features in EC2 and would like to request that the feature be enabled for the cloud kernel. Since the cloud kernel is intended to be optimized for boot time and size for common cloud usecases, it's worth understanding how much code is actually enabled by CONFIG_KSM, and how this affects the size and boot time (if at all). noah
Bug#955232: Please add 9p kernel module to the cloud image.
On Mon, Mar 30, 2020 at 10:33:24AM +0200, Vincent Bernat wrote: > >> Please consider adding kernel module '9p' to the cloud image. It is > >> impossible to passthrough filesystem from hypervisor with the current cloud > >> image and there are no additional packages to install it. The only way that > >> I know to passthrough filesystem currently is to remove > >> linux-image-cloud-amd64 and install linux-image-amd64. > > > > The "cloud" images are specifically meant for running on public clouds, > > and don't support everything that could possibly be exposed to a VM. > > > > Is there a public cloud that supports 9p passthrough? > > Dunno about OP, but for me, it's also useful when using nested > virtualisation. Also, the limitation to "public" cloud seems quite > restrictive. Cloud kernel is used by cloud images, which can be used > directly with libvirt, for example. The "nocloud" VM images generated by the cloud team use the generic kernel, and they're what I'd recommend for use with libvirt and similar systems. The others are targeted toward specific cloud vendors and may not work entirely as expected outside those environments. Some of the supported cloud vendors do support nested virtualization and/or bare-metal host provisioning, so there are cases where 9p could be used to share data between hosts... I'm inclined to agree with Ben. The goal of the cloud kernel is not to support all possible cloud configurations. Host <-> guest filesystem sharing isn't a super common thing in cloud environments, and the generic kernel is always available if needed. Its featureset is a superset of that of the cloud kernel. Enabling 9p won't result in a drastic increase in the installed size, but it is something of a slippery slope. Virtio-fs appears to be the future for this type of use-case, and we do enable this for bullseye cloud kernels. I'd much rather encourage its use instead of the crufty old abuse of a network filesystem that is 9p. noah
What belongs in the Debian cloud kernel?
For buster, we generate a cloud kernel for amd64. For sid/bullseye, we'll also support a cloud kernel for arm64. At the moment, the cloud kernel is the only used in the images we generate for Microsoft Azure and Amazon EC2. It's used in the GCE images we generate as well, but I'm not sure anybody actually uses those. We generate two OpenStack images, one that uses the cloud kernel and another uses the generic kernel. There are open bugs against the cloud kernel requesting that configuration options be turned on there. [1][2][3] These, IMO, highlight a need for some documentation around what is in scope for the cloud kernel, and what is not. This will help us answer requests such as these more consistently, and it will also help our users better understand whether they can expect the cloud kernel to meet their needs or not. At the moment, the primary optimization applied to the cloud kernel focuses on disk space consumed. We disable compilation of drivers that we feel are unlikely to ever appear in a cloud environment. By doing so, we reduce the installed size of the kernel package by roughly 70%. There are other optimization we may apply (see [4] for examples), but we don't yet. Should we simply say "yes" to any request to add functionality to the cloud kernel? None of the drivers will add *that* much to the size of the image, and if people are asking for them, then they've obviously got a use case for them. Or is this a slipperly slope that diminishes the value of the cloud kernel? I can see both sides of the argument, so I'd like to hear what others have to say. If we're not going to say "yes" to all requests, what criteria should we use to determine whether or not to enable a feature? It's rather not leave it as a judgement call. noah 1. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=952108 2. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=955366 3. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=955232 4. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=947759
Re: What belongs in the Debian cloud kernel?
On Thu, Apr 02, 2020 at 10:55:16AM -0700, Ross Vandegrift wrote: > I don't think just saying "yes" automatically is the best approach. But > I'm not sure we can come up with a clear set of rules. Evaluating the > use cases will involve judgment calls about size vs functionality. I > guess I think that's okay. You certainly may be right. I wasn't able to convince myself either way, which is why I posted for additional opinions. > The first two bugs are about nested virtualization. I like the idea of > deciding to support that or not. I don't know much about nested virt, > so I don't have a strong opinion. It seems pretty widely supported on > our platforms. I don't know if it raises performance or security > concerns. So these seem okay to me, as long as we decide to support > nested virt, and there aren't major cons that I'm unaware of. IMO nested virtualization is not something I'd want to see in a "production" environment. Hardware-assisted isolation between VMs is critical for hosting mixed-trust workloads (e.g. VMs owned and controlled by unrelated parties without a mutual trust relationship). Current hardware virtualization extensions, e.g. Intel VTx, only have a concept of a single level of virtualization. Nested virtualization is implemented by trapping and emulating the CPU extensions, and by doing a bunch of mapping of nested guest state to allow it to effectively run as a peer VM of the parent guest in hardware. Some details at [1]. So not only is it painfully complex, but it's also quite slow. This is not to say that there aren't any legitimate use cases for nested virtualization. Only that I'm not sure it's something we want to be optimizing for. > Can you share more about the KSM use case? I'm worried about raising > security concerns for this one. KSM has had a history of enabling > attacks that are sorta serious, but also sorta theoretical. This might > cause upset from infosec folks that freak out about any vulnerability - > even when they don't really understand the magnitude of the risk. I don't have any direct experience with KSM. I can certainly see how it could help with certain classes of workload, though, if it's known that multiple processes with mostly identical state are running. I'm not sure I'd focus too much on the security implications of KSM, though, since it's widely enabled in Debian's generic kernel and kernels distributed by other distros. I don't want to cargo-cult it, but neither do I want to ignore prior art. I don't think there's any reason to drop support for applications making use of KSM in our cloud kernels, though. I can't think of any reason why the feature would be less useful in a cloud environment, and it could certainly save money by allowing the use of smaller instances. noah 1. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/virt/kvm/nested-vmx.rst
Re: What belongs in the Debian cloud kernel?
On Wed, Apr 01, 2020 at 03:15:37PM -0400, Noah Meyerhans wrote: > There are open bugs against the cloud kernel requesting that > configuration options be turned on there. [1][2][3] > 1. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=952108 > 2. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=955366 > 3. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=955232 So, the discussion thus far has focused on these specific requests more than I had hoped. So for now, so we can deal with the current requests, here's what happens if we enable them: These are the kernel .config changes: +CONFIG_VHOST_SCSI=m +CONFIG_KSM=y +CONFIG_NET_9P=m +CONFIG_NET_9P_VIRTIO=m +# CONFIG_NET_9P_XEN is not set +# CONFIG_NET_9P_DEBUG is not set +CONFIG_TARGET_CORE=m +CONFIG_TCM_IBLOCK=m +CONFIG_TCM_FILEIO=m +CONFIG_TCM_PSCSI=m +CONFIG_TCM_USER2=m +# CONFIG_LOOPBACK_TARGET is not set +CONFIG_ISCSI_TARGET=m +# CONFIG_XEN_SCSI_BACKEND is not set +CONFIG_9P_FS=m +CONFIG_9P_FSCACHE=y +CONFIG_9P_FS_POSIX_ACL=y +CONFIG_9P_FS_SECURITY=y +CONFIG_XXHASH=y Because CONFIG_KSM changes statically linked code, it results in a size increase of roughly 12 kB of the compressed kernel. The uncompressed kernel increases by about 852 kB in size. The boot time appears to be unchanged. I don't like the size increase, but this feature is enabled everywhere else and apparently does break some users if it's disabled, so we should enable it. The kernel package installed size increases by roughly 2 MB due to the additional modules we generate for 9P and VHOST_SCSI. So, I think the answer for these specific requests can be affirmative. The cost is small enough that if these features are useful to somebody, then we might as well enable them. noah
Re: What belongs in the Debian cloud kernel?
On Sat, Apr 04, 2020 at 10:17:20AM +0200, Thomas Goirand wrote: > > The first two bugs are about nested virtualization. I like the idea of > > deciding to support that or not. I don't know much about nested virt, > > so I don't have a strong opinion. It seems pretty widely supported on > > our platforms. I don't know if it raises performance or security > > concerns. So these seem okay to me, as long as we decide to support > > nested virt, and there aren't major cons that I'm unaware of. > > There's a big problem when activating nested virt. I have read that Live > migration of VMs can become impossible (ie: for all VMs that are also > host OS for virtualization). As much as I understand, this is because of > the difficulty to support nested MMU. I'm not sure if the situation has > changed or not, but last time I checked this was the case. Ben, do you > know if this has evolved? Remember, nested virtualization works today; nothing we have done would have prevented that. The question is about whether or not we care about enabling features to support use cases that only arise when nested virtualization is in use. The reason nested virtualization breaks live migration is that it shares state between the VM and the underlying hypervisor. The VM is, in a sense, no longer self contained. The nested VMs state is tracked by the parent VM in a VMCS structure, as shown in the nested-vmx.rst doc I linked previously, and the values in that struct need to be mapped to a corresponding list in the hypervisor. Migration would entail some coordination between the hypervisor and the outer VM, as the shared state would need to be kept in sync throughout the process. The sharing of state between the VM and the hypervisor hints at some of the potential security concerns around nested virtualization in mixed-trust environments. > So, when I'm being asked about it, my answer from an OpenStack operator > point of view, is always a big "NO !". I want to be able to service my > compute nodes. This means being able to live-migrate the workload away, > otherwise, customers may notice. Whether or not you support nested virt on your infrastructure is a deployment choice, not a choice Debian needs to make. noah
Bug#955366: 955366 is Important
Control: severity -1 important Raising this to Important. The lack of a KSM is a regression from the generic kernel that is impacting the usefulness of this kernel build in the environment in which it's intended to be used. This should get fixed in buster.
Bug#955366: 955366 is Important
Control: tags -1 + patch Proposed fix for buster at https://salsa.debian.org/kernel-team/linux/-/merge_requests/229
Bug#956703: linux-image-5.5: 5.5 kernel seems to break pulseaudio HDMI detection
On Tue, Apr 14, 2020 at 02:06:30PM +0100, Simon John wrote: > Booting into 5.5 on Sid gives me no audio out via HDMI. I can confirm similar HDMI audio breakage with 5.5.13 on a Thinkpad X1 Carbon (gen2) with the following audio devices: 00:03.0 Audio device: Intel Corporation Haswell-ULT HD Audio Controller (rev 0b) Subsystem: Lenovo Haswell-ULT HD Audio Controller Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- Kernel driver in use: snd_hda_intel Kernel modules: snd_hda_intel 00:1b.0 Audio device: Intel Corporation 8 Series HD Audio Controller (rev 04) Subsystem: Lenovo 8 Series HD Audio Controller Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- Kernel driver in use: snd_hda_intel Kernel modules: snd_hda_intel
Bug#956703: linux-image-5.5: 5.5 kernel seems to break pulseaudio HDMI detection
On Tue, Apr 14, 2020 at 02:06:30PM +0100, Simon John wrote: > Package: src:linux > Version: 5.5.13-2 > > Booting into 5.5 on Sid gives me no audio out via HDMI. > HDMI audio seems fixed for me with 5.5.17, recently uploaded to unstable. Is it better for you?
Bug#890343: linux: make fq_codel default for default_qdisc
On Thu, Apr 23, 2020 at 03:34:06PM -0700, Matt Taggart wrote: > fq_codel is better in every way than pfifo_fast and I am unaware of any > reason why it would not be a better default. (but don't trust me, ask the > kernel networking experts) Isn't CAKE supposed to be even better than fq_codel, including better handling of both large numbers of flows (e.g. busy routers) and small systems with limited resources. https://www.bufferbloat.net/projects/codel/wiki/Cake/ If we consider a change (which I think we should), is there a reason we wouldn't go with CAKE? noah
Bug#968623: src:linux: buster fails to boot successfully on AWS arm64 bare-metal instances
Package: src:linux Version: 4.19.132-1 Severity: important Tags: buster Buster fails to fully initialize the hardware on AWS arm64 bare-metal instances (e.g. m6g.metal). The issue is fixed with the patch series from https://lore.kernel.org/linux-arm-kernel/20190615002359.29577-2-b...@kernel.crashing.org/ that adds support for preservation of the PCI bridge configuration upon request by the firmware. I have backported the above patch series to 4.19 and will open a merge request. noah
Bug#968623: src:linux: buster fails to boot successfully on AWS arm64 bare-metal instances
Control: tags -1 + patch MR available at https://salsa.debian.org/kernel-team/linux/-/merge_requests/263
Bug#941284: Wishlist/RFC: Use CONFIG_HZ=100 in linux-image-cloud-*
On Fri, Sep 27, 2019 at 01:15:29PM -0700, Flavio Veloso wrote: > Since linux-image-cloud-* packages are created for cloud environments -- > read: servers which do not need desktop-level responsiveness --, wouldn't it > be beneficial to build the kernels with CONFIG_HZ set to 100? For what it's worth, the Amazon Linux 2 4.14.x kernel also ships with CONFIG_HZ=250. We obviously don't need to use the same settings, but that kernel specifically targets cloud deployments, and its maintainers do not see a need to set CONFIG_HZ=100. I don't know what considerations were taken into account when choosing the value for that variable at AWS. noah
Bug#941291: Amazon ENA driver update for stable
Package: src:linux Version: 4.19.67-2 ENA is an ethernet adaptor used on Amazon EC2 cloud instances. Upstream has recently merged a number of bug fixes and enhancements, and it would be nice to have these available in stable. Specific upstream changesets that I'm interested in are: https://lore.kernel.org/netdev/20190212.110632.499796234007955726.da...@davemloft.net/ https://lore.kernel.org/netdev/20190504.001749.585621906089996460.da...@davemloft.net/ https://lore.kernel.org/netdev/20190603.133056.1755579912817273080.da...@davemloft.net/ https://lore.kernel.org/netdev/20190612.112249.1252227316058010690.da...@davemloft.net/ https://lore.kernel.org/netdev/20190623.083930.762200013774329614.da...@davemloft.net/ https://lore.kernel.org/netdev/20190625.140934.145849418200881936.da...@davemloft.net/ https://lore.kernel.org/netdev/20190916.220620.564607753604799412.da...@davemloft.net/#t In theory it would be possible to pare down the list of commits to something more tightly focused, but the level of effort involved (and potential for regressions) would be quite a bit higher. Further, I would rather avoid diverging too far from what's in mainline. I will provide a merge request on salsa with proposed changes.
Bug#941291: Acknowledgement (Amazon ENA driver update for stable)
Proposed implementation in https://salsa.debian.org/kernel-team/linux/merge_requests/172
Bug#931341: linux-image-4.19.0-5-cloud-amd64 does not have /dev/rtc, used by GCE images
Proposed fixes for unstable and stable (respectively) are at: https://salsa.debian.org/kernel-team/linux/merge_requests/179 https://salsa.debian.org/kernel-team/linux/merge_requests/178
Re: Latest kernel and headers in buster-backports
On Tue, Nov 26, 2019 at 10:07:45AM +0100, Andreas Heinlein wrote: > > I noticed that linux-image-amd64 is currently missing in buster-backports > since a few days. I guess this is because the signed kernel images are not > available yet. Still, linux-headers-amd64 exists in buster backports and > pulls in linux-headers-5.3... > > We use the latest kernel image and headers from buster-backports for > automated installations using FAI, and this situation breaks a few things, > including dkms modules not being compiled and so on. > > I know that backports isn't supposed to be as well supported as the "main" > repo, but still I'd like to know if it is possible to keep headers and image > metapackages in sync in backports. > The thread beginning here has the details: https://lists.debian.org/debian-backports/2019/11/msg9.html It is a known issue and will be resolved "soon". noah
Bug#948519: insufficient boot-time entropy on arm64 virtual machines
Package: src:linux Version: 4.19.67-2+deb10u2 Severity: important See the thread at https://lists.debian.org/debian-cloud/2020/01/threads.html#00013 for some context. When launching arm64 VMs on Amazon EC2, a lack of entropy at boot results in the full boot process taking several minutes, when the expectation is that it take a small number of seconds (<10). Analysis of the boot process shows the ssh key generation is the culprit, taking nearly 3 minutes. admin@ip-10-0-1-87:~$ cloud-init analyze blame -- Boot Record 01 -- 165.77300s (init-network/config-ssh) The 5.4 kernel currently in sid does not experience this lack of entropy. It has been suggested that upstream commit 50ee7529ec45 ("random: try to actively add entropy rather than passively wait for it") may be the difference here, but I have not confirmed this. A suggested workaround has been to install haveged in the image, but this tends to make crypto people frown.
Bug#931644: Buster kernel entropy pool too low on VM boot
On Thu, Jul 11, 2019 at 09:42:17AM -0400, Michael J. Redd wrote: > > The release notes for buster do mention this issue and provide a > > link to: > > > > https://wiki.debian.org/BoottimeEntropyStarvation > > > > which has your Haveged solution as one of its suggestions. > > > > D'oh! Serves me right for just skimming the release notes, then. After > doing some in-depth reading, this is a problem for the Linux community > at large. Wow. While I'm glad the kernel's getting choosier about where > and how to harvest entropy and can personally live with the ~30 seconds > added to VM boot times, it could be painful to, for example, bootstrap > a Linux guest on AWS for the first time and wait for the initial SSH > keys to be created. > > Will be interesting to see how this evolves over time. In the meantime, > as this is not actually a kernel defect, I suppose this bug can be > closed. I suspect that this bug might end up being mergeable with https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=948519. In that bug, I am investigating cherry-picking commit 50ee7529ec45 from the linux mainline branch for buster. At least on the arm64 ec2 instances where I've tested, this change resolves the issue. If I provide a package for you, would you be able to test it in your environment to see if the proposed patch addresses the problem there? Thanks noah https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=50ee7529ec45
Bug#948519: insufficient boot-time entropy on arm64 virtual machines
On Thu, Jan 09, 2020 at 02:00:01PM -0500, Noah Meyerhans wrote: > The 5.4 kernel currently in sid does not experience this lack of > entropy. It has been suggested that upstream commit 50ee7529ec45 > ("random: try to actively add entropy rather than passively wait for > it") may be the difference here, but I have not confirmed this. I've tested 4.19 with the changes from 50ee7529ec45, and it appears to do the expected thing. The kernel claims to have enough entropy at boot that ssh host key generation happens quickly. This change is likely to also address #931644. I've asked the submitter of that bug if they'd be able to test a proposed fix. I will prepare a merge request and note it here when it's available. noah
Bug#948519: Info received (Bug#948519: insufficient boot-time entropy on arm64 virtual machines)
Control: tags -1 + patch Proposed solution submitted as https://salsa.debian.org/kernel-team/linux/merge_requests/202
Bug#947759: Configuration optimizations for the cloud variant
On Mon, Jan 20, 2020 at 04:38:55PM -0800, Josh Triplett wrote: > Following up on this, here's a simplified list of optimizations for the > cloud variant in one place, taking into account the previous reply. > Would it help to get this in the form of a patch or MR on > https://salsa.debian.org/kernel-team/linux/ ? Hi Josh. I started some work on integrating and testing your proposed changes in a private branch at https://salsa.debian.org/noahm/linux/tree/cloud-optimizations-bug947759, but haven't gotten to the point of creating an MR yet. I can likely pick this up again this week, but if you create one first, that's fine too. One thing to note is that MR !193 changes the layout of the cloud configs as it introduces an arm64 cloud flavour. It hasn't been fully reviewed yet, but there will be some merging to do if you work on your MR independently of that. https://salsa.debian.org/kernel-team/linux/merge_requests/193 Thank you for opening this bug! noah
Bug#947759: Configuration optimizations for the cloud variant
Before optimizations: $ systemd-analyze Startup finished in 7.828s (kernel) + 22.332s (userspace) = 30.161s graphical.target reached after 20.312s in userspace With optimizations: $ systemd-analyze Startup finished in 1.968s (kernel) + 6.536s (userspace) = 8.504s graphical.target reached after 6.197s in userspace Only tested so far on an EC2 t3.medium, so results may vary elsewhere, but that's nice. :) I'll post a WIP MR on salsa next. Some cleanup is needed still. noah
Bug#947759: Configuration optimizations for the cloud variant
On Tue, Feb 04, 2020 at 03:48:32PM -0800, Josh Triplett wrote: > I would suggest testing on a c5.large. t2 and t3 have shared CPUs, so > they have less consistent boot time. c5.large is about the same cost as > t3.large, but will have far more consistent performance. Performance definitely seems to vary quite a bit. Here are a few samples from c5.large instances in us-west-2: 5.5 "generic" kernel: $ systemd-analyze Startup finished in 4.323s (kernel) + 11.189s (userspace) = 15.513s graphical.target reached after 9.865s in userspace 5.5 "cloud" with optimizations: $ systemd-analyze Startup finished in 7.273s (kernel) + 21.984s (userspace) = 29.258s graphical.target reached after 19.811s in userspace $ systemd-analyze Startup finished in 4.319s (kernel) + 13.684s (userspace) = 18.003s graphical.target reached after 12.321s in userspace $ systemd-analyze Startup finished in 3.327s (kernel) + 9.846s (userspace) = 13.174s graphical.target reached after 8.831s in userspace The optimized timings are all taken from the initial boot of newly launched instances. It's certainly possible that things will look better with more data, but it's not clear yet that this change is an improvement in all cases. > > I'll post a WIP MR on salsa next. Some cleanup is needed still. > > Thank you for working on this! > The MR is here: https://salsa.debian.org/kernel-team/linux/merge_requests/206 I'm happy to share binary and/or source .debs and/or AMIs if you'd like to run some of your own tests. > Have you confirmed that with the optimizations, you can boot without > needing an initramfs? I've confirmed that the kernel can boot on c5 and t3 instances without an initramfs present at all. However, the Xen backed EC2 instance types would also need to statically link (at least) ATA_PIIX, ATA_GENERIC, and XEN_BLKDEV_FRONTEND if we wanted to provide kernels that could be generally useful in EC2 without an initramfs. noah
Bug#981186: linux: Enable CMN-600 interconnect on arm64
On Wed, Jan 27, 2021 at 12:57:07PM +, Wookey wrote: > Current arm hardware such as graviton2 (AWS arm64 hardware) has > 'Coherent Mesh Network' interconnect (between components in a > soc). It's important that support for this is built in the kernel so > it can be used. > > This requires CONFIG_ARM_CMN=y To be precise, this driver is needed for perf event monitoring of this interconnect. The interconnect itself is always in use. On Amazon EC2, these PMU events are only exposed on the bare-metal instances (e.g. m6g.metal), not the VMs. We should still enable support for this driver, in any case. noah
Bug#983923: linux-image-4.19.0-13-cloud-amd64: Please add CONFIG_MAXSMP to the linux-image-cloud-amd64 kernel
On Wed, Mar 03, 2021 at 05:35:42PM +0100, Louis Bouchard wrote: > Thank you for the quick update. I just want to mention that this makes the > Debian Buster cloud image unusable for any VM with more than 64 cpus. Is it the number of physical cores that matters, rather than the SMT threads? Because on a 96 core SMT system, it works today: admin@ip-10-0-0-75:~$ uname -a && ec2metadata --instance-type && lscpu Linux ip-10-0-0-75 4.19.0-14-cloud-amd64 #1 SMP Debian 4.19.171-2 (2021-01-30) x86_64 GNU/Linux m5a.24xlarge Architecture:x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 48 bits physical, 48 bits virtual CPU(s): 96 On-line CPU(s) list: 0-95 Thread(s) per core: 2 Core(s) per socket: 24 Socket(s): 2 NUMA node(s):6 Vendor ID: AuthenticAMD CPU family: 23 Model: 1 Model name: AMD EPYC 7571 Stepping:2 CPU MHz: 2550.330 BogoMIPS:4399.61 Hypervisor vendor: KVM Virtualization type: full L1d cache: 32K L1i cache: 64K L2 cache:512K L3 cache:8192K NUMA node0 CPU(s): 0-7,48-55 NUMA node1 CPU(s): 8-15,56-63 NUMA node2 CPU(s): 16-23,64-71 NUMA node3 CPU(s): 24-31,72-79 NUMA node4 CPU(s): 32-39,80-87 NUMA node5 CPU(s): 40-47,88-95 Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid amd_dcm aperfmperf tsc_known_freq pni pclmulqdq ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand hypervisor lahf_lm cmp_legacy cr8_legacy abm sse4a misalignsse 3dnowprefetch topoext perfctr_core vmmcall fsgsbase bmi1 avx2 smep bmi2 rdseed adx smap clflushopt sha_ni xsaveopt xsavec xgetbv1 clzero xsaveerptr arat npt nrip_save Do any of the cloud providers supported by the cloud kernel build (primarily AWS and Azure) offer VMs with >64 physical cores? noah
Bug#986741: Please enable CONFIG_IP_PNP_DHCP=y in cloud image
On Tue, Apr 13, 2021 at 11:36:11AM +0200, Bastian Blank wrote: > > > Where was that discussed? > > It was discussed in > > https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=947759 > > , with responses from both Ben and Noah. > > As this is incomplete at best, I intend to revert that change. > > Otherwise it at least needs in addition: > - hyperv pci support (for nvme), > - hyperv block and > - virtio-scsi. This should probably be discussed in depth outside of this bug, but I do not think this is the right approach. The kernel config changes have been in place for over a year, and were merged only after discussion both on salsa and the BTS. They accomplish the desired effect, which is to allow the cloud kernel to boot without an initrd on common cloud instance types (specifically AWS Nitro instance types). While this is not the default behavior for any of our cloud images, it is simple for users to enable it on derivative images if they can benefit from the reduced boot time. If we want to support initrd-less booting on instances aside from Nitro instance types, that's great, and we should consider doing that. That would be much more beneficial to our users than reverting the change. > However this bug is about dhcp support. If there is no network device > support available, how does it do dhcp? I'd also argue that NIC drivers (in particular ena.ko, used on Nitro instances) should be left configured as modules, even if we do want to support initrd-less booting. AWS publishes an out-of-tree variant of the ENA driver that may be ahead of what's in the stable kernel tree, and some users may have a need to run that. noah signature.asc Description: PGP signature
Bug#625914: linux-image-2.6.38-2-amd64: bridging is not interacting well with multicast in 2.6.38-4
Package: linux-2.6 Version: 2.6.38-3 Severity: normal Hi. I've got a system that hosts several kvm virtual hosts. The VMs access the network via tap devices bridged with a physical interface. After upgrading to linux-image-2.6.38-2-amd64_2.6.38-4, I noticed that the virtualhosts were not autoconfiguring their IPv6 interfaces. Debugging revealed that no multicast was passing over the bridge. The bridge configuration is: bridge name bridge id STP enabled interfaces br0 8000.0002e3080eb5 no eth1 tap0 tap1 tap2 If I attach tcpdump to br0, I can see multicast (e.g. IPv6 Neighbor Solicitation) packets. However, if I attach tcpdump to eth1, I do not see multicast packets sourced from one of the VMs. Downgrading to 2.6.38-3 solves the problem. noah -- Package-specific info: ** Version: Linux version 2.6.38-2-amd64 (Debian 2.6.38-3) (b...@decadent.org.uk) (gcc version 4.4.5 (Debian 4.4.5-15) ) #1 SMP Thu Apr 7 06:43:20 UTC 2011 ** Command line: BOOT_IMAGE=/vmlinuz root=UUID=c5ed1e31-1b76-44fa-a32d-12aa816c51eb ro quiet ** Not tainted ** Kernel log: [ 1146.028039] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1146.028040] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1146.028042] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1146.028044] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1146.028046] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1146.028047] [ 1146.028050] radeon :01:05.0: DVI-D-1: EDID block 0 invalid. [ 1146.028053] [drm:radeon_dvi_detect] *ERROR* DVI-D-1: probed a monitor but no|invalid EDID [ 1156.118932] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 1 [ 1156.118936] [drm:drm_edid_block_valid] *ERROR* Raw EDID: [ 1156.118939] <3>01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118941] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118944] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118946] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118949] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118951] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118953] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118956] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.118957] [ 1156.168710] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 1 [ 1156.168712] [drm:drm_edid_block_valid] *ERROR* Raw EDID: [ 1156.168715] <3>01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168717] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168720] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168722] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168725] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168727] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168729] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168732] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.168734] [ 1156.218447] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 1 [ 1156.218450] [drm:drm_edid_block_valid] *ERROR* Raw EDID: [ 1156.218452] <3>01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218454] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218457] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218459] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218462] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218464] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218466] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218469] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.218471] [ 1156.268287] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 1 [ 1156.268289] [drm:drm_edid_block_valid] *ERROR* Raw EDID: [ 1156.268292] <3>01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.268294] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.268297] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.268299] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 1156.268301] <3>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Bug#625914: linux-image-2.6.38-2-amd64: bridging is not interacting well with multicast in 2.6.38-4
On Tue, May 10, 2011 at 03:38:44AM +0100, Ben Hutchings wrote: > This is pretty weird. Debian version 2.6.38-3 has a few bridging > changes from stable 2.6.38.3 and 2.6.38.4, but they don't look like they > would cause this. I have apparently filed the bug against the wrong version of Debian's kernel. 2.6.38-3 is not affected, and works as expected. The change was introduced in -4. That may have been clear from the report itself, but the report was filed against -3. I've fixed that in the BTS. I've also confirmed that -5 is affected, to no great surprise. I'll investigate further. noah signature.asc Description: Digital signature
Bug#625914: linux-image-2.6.38-2-amd64: bridging is not interacting well with multicast in 2.6.38-4
On Tue, May 10, 2011 at 01:42:49PM +0100, Ben Hutchings wrote: > > > This is pretty weird. Debian version 2.6.38-3 has a few bridging > > > changes from stable 2.6.38.3 and 2.6.38.4, but they don't look like they > > > would cause this. > > > > I have apparently filed the bug against the wrong version of Debian's > > kernel. 2.6.38-3 is not affected, and works as expected. The change > > was introduced in -4. That may have been clear from the report itself, > > but the report was filed against -3. I've fixed that in the BTS. > > I gathered that, and then made the same mistake in writing the above! > The version with the regression, 2.6.38-4, includes the changes from > stable 2.6.38.3 and 2.6.38.4 With a little help from git bisect, I've tracked this regression down to the following commit to the stable-2.6.38.y tree: commit 5f1c356a3fadc0c19922d660da723b79bcc9aad7 Author: Herbert Xu Date: Fri Mar 18 05:27:28 2011 + bridge: Reset IPCB when entering IP stack on NF_FORWARD [ Upstream commit 6b1e960fdbd75dcd9bcc3ba5ff8898ff1ad30b6e ] Whenever we enter the IP stack proper from bridge netfilter we need to ensure that the skb is in a form the IP stack expects it to be in. The entry point on NF_FORWARD did not meet the requirements of the IP stack, therefore leading to potential crashes/panics. This patch fixes the problem. Signed-off-by: Herbert Xu Acked-by: Stephen Hemminger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman The diff is diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 4b5b66d..49d50ea 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -741,6 +741,9 @@ static unsigned int br_nf_forward_ip(unsigned int hook, struct sk_buff *skb, nf_bridge->mask |= BRNF_PKT_TYPE; } + if (br_parse_ip_options(skb)) + return NF_DROP; + /* The physdev module checks on this */ nf_bridge->mask |= BRNF_BRIDGED; nf_bridge->physoutdev = skb->dev; If I revert this change, network connectivity functions as expected for the VMs on this host. I don't know enough about this change or the problem it was supposed to solve to be able to guess about what's going wrong. noah signature.asc Description: Digital signature
Bug#625914: [Bridge] Bug#625914: linux-image-2.6.38-2-amd64: bridging is not interacting well with multicast in 2.6.38-4
On Tue, May 10, 2011 at 03:11:00PM -0700, Stephen Hemminger wrote: > There were two more follow on commits in stable related to this. > I recommend merging 2.6.38.6 which includes these. The problem still exists in the current 2.6.38.6. Backing out 5f1c356a still solves the problem there. I have not yet tried anything outside the stable-2.6.38.y tree, but it seems like these same changes are present there, and it's unlikely that other releases will work any better. noah signature.asc Description: Digital signature
Bug#625914: [Bridge] Bug#625914: linux-image-2.6.38-2-amd64: bridging is not interacting well with multicast in 2.6.38-4
On Thu, May 12, 2011 at 04:43:22PM -0700, Stephen Hemminger wrote: > > > There were two more follow on commits in stable related to this. > > > I recommend merging 2.6.38.6 which includes these. > > > > The problem still exists in the current 2.6.38.6. Backing out 5f1c356a > > still solves the problem there. > > > > I have not yet tried anything outside the stable-2.6.38.y tree, but it > > seems like these same changes are present there, and it's unlikely that > > other releases will work any better. > > Does this fix the problem? The tap driver allocates an skb and throws > it into the receive path, but the skb does not have the same padding > as normal skb's received. > > --- a/drivers/net/tun.c 2011-05-12 16:36:15.231347935 -0700 > +++ b/drivers/net/tun.c 2011-05-12 16:36:38.503464573 -0700 > @@ -614,7 +614,7 @@ static __inline__ ssize_t tun_get_user(s > } > > if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { > - align = NET_IP_ALIGN; > + align = NET_IP_ALIGN + NET_SKB_PAD; > if (unlikely(len < ETH_HLEN || >(gso.hdr_len && gso.hdr_len < ETH_HLEN))) > return -EINVAL; > Sorry, this does not fix the problem. noah signature.asc Description: Digital signature