This bug was fixed in the package linux - 4.15.0-39.42
---------------
linux (4.15.0-39.42) bionic; urgency=medium
* linux: 4.15.0-39.42 -proposed tracker (LP: #1799411)
* Linux: insufficient shootdown for paging-structure caches (LP: #1798897)
- mm: move tlb_table_flush to tlb_flush_mmu_free
- mm/tlb: Remove tlb_remove_table() non-concurrent condition
- mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE
- [Config] CONFIG_HAVE_RCU_TABLE_INVALIDATE=y
* Ubuntu18.04: GPU total memory is reduced (LP: #1792102)
- Revert "powerpc/powernv: Increase memory block size to 1GB on radix"
* arm64: snapdragon: reduce boot noise (LP: #1797154)
- [Config] arm64: snapdragon: DRM_MSM=m
- [Config] arm64: snapdragon: SND*=m
- [Config] arm64: snapdragon: disable ARM_SDE_INTERFACE
- [Config] arm64: snapdragon: disable DRM_I2C_ADV7511_CEC
- [Config] arm64: snapdragon: disable VIDEO_ADV7511, VIDEO_COBALT
* [Bionic] CPPC bug fixes (LP: #1796949)
- ACPI / CPPC: Update all pr_(debug/err) messages to log the susbspace id
- cpufreq: CPPC: Don't set transition_latency
- ACPI / CPPC: Fix invalid PCC channel status errors
* regression in 'ip --family bridge neigh' since linux v4.12 (LP: #1796748)
- rtnetlink: fix rtnl_fdb_dump() for ndmsg header
* screen displays abnormally on the lenovo M715 with the AMD GPU (Radeon Vega
8 Mobile, rev ca, 1002:15dd) (LP: #1796786)
- drm/amd/display: Fix takover from VGA mode
- drm/amd/display: early return if not in vga mode in disable_vga
- drm/amd/display: Refine disable VGA
* arm64: snapdragon: WARNING: CPU: 0 PID: 1 arch/arm64/kernel/setup.c:271
reserve_memblock_reserved_regions (LP: #1797139)
- SAUCE: arm64: Fix /proc/iomem for reserved but not memory regions
* The front MIC can't work on the Lenovo M715 (LP: #1797292)
- ALSA: hda/realtek - Fix the problem of the front MIC on the Lenovo M715
* Keyboard backlight sysfs sometimes is missing on Dell laptops (LP: #1797304)
- platform/x86: dell-smbios: Correct some style warnings
- platform/x86: dell-smbios: Rename dell-smbios source to dell-smbios-base
- platform/x86: dell-smbios: Link all dell-smbios-* modules together
- [Config] CONFIG_DELL_SMBIOS_SMM=y, CONFIG_DELL_SMBIOS_WMI=y
* rpi3b+: ethernet not working (LP: #1797406)
- lan78xx: Don't reset the interface on open
* 87cdf3148b11 was never backported to 4.15 (LP: #1795653)
- xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto
* [Ubuntu18.04][Power9][DD2.2]package installation segfaults inside debian
chroot env in P9 KVM guest with HTM enabled (kvm) (LP: #1792501)
- KVM: PPC: Book3S HV: Fix guest r11 corruption with POWER9 TM workarounds
* Provide mode where all vCPUs on a core must be the same VM (LP: #1792957)
- KVM: PPC: Book3S HV: Provide mode where all vCPUs on a core must be the
same
VM
* fscache: bad refcounting in fscache_op_complete leads to OOPS (LP: #1797314)
- SAUCE: fscache: Fix race in decrementing refcount of op->npages
* CVE-2018-9363
- Bluetooth: hidp: buffer overflow in hidp_process_report
* CVE-2017-13168
- scsi: sg: mitigate read/write abuse
* [Bionic] ACPI / PPTT: use ACPI ID whenever ACPI_PPTT_ACPI_PROCESSOR_ID_VALID
is set (LP: #1797200)
- ACPI / PPTT: use ACPI ID whenever ACPI_PPTT_ACPI_PROCESSOR_ID_VALID is set
* [Bionic] arm64: topology: Avoid checking numa mask for scheduler MC
selection (LP: #1797202)
- arm64: topology: Avoid checking numa mask for scheduler MC selection
* crypto/vmx - Backport of Fix sleep-in-atomic bugs patch for 18.04
(LP: #1790832)
- crypto: vmx - Fix sleep-in-atomic bugs
* hns3: autoneg settings get lost on down/up (LP: #1797654)
- net: hns3: Fix for information of phydev lost problem when down/up
* not able to unwind the stack from within __kernel_clock_gettime in the Linux
vDSO (LP: #1797963)
- powerpc/vdso: Correct call frame information
* Signal 7 error when running GPFS tracing in cluster (LP: #1792195)
- powerpc/mm/books3s: Add new pte bit to mark pte temporarily invalid.
- powerpc/mm/radix: Only need the Nest MMU workaround for R -> RW transition
* Support Edge Gateway's WIFI LED (LP: #1798330)
- SAUCE: mwifiex: Switch WiFi LED state according to the device status
* Support Edge Gateway's Bluetooth LED (LP: #1798332)
- SAUCE: Bluetooth: Support for LED on Edge Gateways
* USB cardreader (0bda:0328) make the system can't enter s3 or hang
(LP: #1798328)
- usb: Don't disable Latency tolerance Messaging (LTM) before port reset
* CVE-2018-15471
- xen-netback: fix input validation in xenvif_set_hash_mapping()
* CVE-2018-16658
- cdrom: Fix info leak/OOB read in cdrom_ioctl_drive_status
* [Bionic] Update ThunderX2 implementation defined pmu core events
(LP: #1796904)
- perf vendor events arm64: Update ThunderX2 implementation defined pmu core
events
* the machine of lenovo M715 with the AMD GPU (Radeon Vega 8 Mobile, rev ca,
1002:15dd) often hangs randomly (LP: #1796789)
- drm/amd: Add missing fields in atom_integrated_system_info_v1_11
* [18.04] GLK hang after a while (LP: #1760545)
- drm/i915/glk: Add MODULE_FIRMWARE for Geminilake
* Fix usbcore.quirks when used at boot (LP: #1795784)
- usb: core: safely deal with the dynamic quirk lists
-- Kleber Sacilotto de Souza <kleber.so...@canonical.com> Tue, 23 Oct
2018 14:44:55 +0000
** Changed in: linux (Ubuntu Bionic)
Status: Fix Committed => Fix Released
** CVE added: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2017-13168
** CVE added: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2018-15471
** CVE added: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2018-16658
** CVE added: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2018-9363
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1792195
Title:
Signal 7 error when running GPFS tracing in cluster
Status in The Ubuntu-power-systems project:
Fix Committed
Status in linux package in Ubuntu:
In Progress
Status in linux source package in Bionic:
Fix Released
Status in linux source package in Cosmic:
Fix Committed
Bug description:
== SRU Justification ==
IBM is requesting these commits in bionic and cosmic. These commits
also rely on commit 7acf50e4efa6, which was SRU'd in bug 1792102.
Description of bug:
GPFS mmfsd daemon is mapping shared tracing buffer(allocated from kernel
driver using vmalloc) and then writing trace records from user space threads
in parallel. While the SIGBUS happened, the access virtual memory address
is in the mapped range, no overflow on access.
The root cause is that for PTEs created by a driver at mmap time (ie, that
aren't created dynamically at fault time), it's not legit for
ptep_set_access_flags()
to make them invalid even temporarily. A concurrent access while they are
invalid will be unable to service the page fault and will cause as SIGBUS.
== Fixes ==
bd0dbb73e013 ("powerpc/mm/books3s: Add new pte bit to mark pte temporarily
invalid.")
f08d08f3db55 ("powerpc/mm/radix: Only need the Nest MMU workaround for R ->
RW transition")
== Regression Potential ==
Low. Limited to powerpc.
== Test Case ==
A test kernel was built with these patches and tested by IBM.
IBM states the test kernel resolved the bug.
-- Problem Description --
GPFS mmfsd daemon is mapping shared tracing buffer(allocated from kernel
driver using vmalloc) and then writing trace records from user space threads in
parallel. While the SIGBUS happened, the access virtual memory address is in
the mapped range, no overflow on access.
Worked with Benjamin Herrenschmidt on GPFS tracing kernel driver code
and he made a suggestion as workaround on the driver code to bypass
the problem, and it works....
the workaround code change as below:
- rc = remap_pfn_range(vma, start, pfn, PAGE_SIZE, PAGE_SHARED);
+ rc = remap_pfn_range(vma, start, pfn, PAGE_SIZE,
__pgprot(pgprot_val(PAGE_SHARED)|_PAGE_DIRTY);
As Benjamin mentioned, this is a Linux kernel bug and this is just a
workaround. He will give the details about the kernel bug and why this
workaround works....
The root cause is that for PTEs created by a driver at mmap time (ie,
that aren't created dynamically at fault time), it's not legit for
ptep_set_access_flags() to make them invalid even temporarily. A
concurrent access while they are invalid will be unable to service the
page fault and will cause as SIGBUS.
Thankfully such PTEs shouldn't normally be the subject of a RO->RW
privilege escalation.
What happens is that the GPFS driver creates the PTEs using
remap_pfn_range(...,PAGE_SHARED).
PAGE_SHARED has _PAGE_ACCESSED (R) but not _PAGE_DIRTY (C) set.
Thus on the first write, we try set C and while doing so, hit the
above workaround, which causes the problem described earlier.
The proposed patch will ensure we only do the Nest MMU hack when
changing _PAGE_RW and not for normal R/C updates.
The workaround tested by the GPFS team consists of adding _PAGE_DIRTY
to the mapping created by remap_pfn_range() to avoid the RC update
fault completely.
This is fixed by these:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd0dbb73e01306a1060e56f81e5fe287be936477
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f08d08f3db55452d31ba4a37c702da6245876b96
Since DD1 support is still in (ie,
2bf1071a8d50928a4ae366bb3108833166c2b70c is not applied) the second
doesn't apply cleanly. Did you want that attached?
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-power-systems/+bug/1792195/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
