On Wed, Feb 17, 2016 at 8:18 AM, Daniel Vetter <daniel at ffwll.ch> wrote: > On Tue, Feb 16, 2016 at 09:26:35AM -0800, Andy Lutomirski wrote: >> On Tue, Feb 16, 2016 at 9:12 AM, Andy Lutomirski <luto at amacapital.net> >> wrote: >> > On Tue, Feb 16, 2016 at 8:12 AM, Daniel Vetter <daniel at ffwll.ch> wrote: >> >> On Mon, Feb 15, 2016 at 06:58:33AM -0800, Andy Lutomirski wrote: >> >>> On Sun, Feb 14, 2016 at 6:59 PM, Andy Lutomirski <luto at kernel.org> >> >>> wrote: >> >>> > Hi- >> >>> > >> >>> > On 4.5-rc3 on a Dell XPS 13 9350 (Skylake i915, no nvidia on this >> >>> > model), shortly after resume, I saw a single black flash on the >> >>> > screen. The log said: >> >>> > >> >>> > [Feb13 07:05] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* >> >>> > CPU pipe A FIFO underrun >> >>> > >> >>> > I haven't seen this on 4.4. >> >>> > >> >>> > I'd be happy to dig up debugging info, but I don't know what would be >> >>> > useful. I have no i915 module options set. >> >>> >> >>> It's flashing quite frequently now, although I seem to get the >> >>> underrun warning only once per resume. >> >> >> >> We shut up the warning irq source to avoid hijacking an entire cpu core >> >> ;-) >> >> >> >> There's a fix from Matt right after 4.5-rc4 in Linus' branch. I'm hoping >> >> that should help. >> > >> > Do you mean: >> > >> > commit e2e407dc093f530b771ee8bf8fe1be41e3cea8b3 >> > Author: Matt Roper <matthew.d.roper at intel.com> >> > Date: Mon Feb 8 11:05:28 2016 -0800 >> > >> > drm/i915: Pretend cursor is always on for ILK-style WM calculations >> > (v2) >> > >> > If so, it didn't help. I'm currently doing a full rebuild just in >> > case I messed something up, though. >> > >> >> Definitely not fixed. It seems to be okay after a reboot until the >> first suspend/resume. >> >> This happened after resuming. Five cents says it's the root cause. > > That's interesting, but doesn't ring a bell unfortunately. Can you try to > attempt a bisect? >
I'm giving up on my attempt to bisect for now. After a bunch of false starts to avoid this crap, I'm stuck at 651174a4a0ccaf41e14fadc4bc525d61ae7f7b18, which is based on 4.3-rc3 and doesn't merge cleanly up to 4.4. It's also annoying because it reproduces reasonably quickly but not instantaneously, and I can never reproduce it before a suspend/resume, so my bisection attempts are full of errors. --Andy > Thanks, Daniel > >> >> [ 160.361200] WARNING: CPU: 2 PID: 2512 at >> drivers/gpu/drm/i915/intel_uncore.c:599 >> hsw_unclaimed_reg_debug+0x69/0x90 [i915]() >> [ 160.361209] Unclaimed register detected before writing to register 0x20a8 >> [ 160.361213] Modules linked in: rfcomm fuse ccm cmac xt_CHECKSUM >> ipt_MASQUERADE nf_nat_masquerade_ipv4 tun nf_conntrack_netbios_ns >> nf_conntrack_broadcast ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 >> xt_conntrack ebtable_filter ebtable_nat ebtable_broute bridge stp llc >> ebtables ip6table_raw ip6table_mangle ip6table_security ip6table_nat >> nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_filter >> ip6_tables iptable_raw iptable_mangle iptable_security iptable_nat >> nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack bnep >> arc4 iwlmvm mac80211 snd_hda_codec_hdmi snd_hda_codec_realtek >> hid_multitouch snd_hda_codec_generic iwlwifi snd_hda_intel intel_rapl >> snd_hda_codec x86_pkg_temp_thermal coretemp kvm_intel snd_hwdep >> cfg80211 snd_hda_core kvm snd_seq uvcvideo snd_seq_device >> i2c_designware_platform >> [ 160.361385] i2c_designware_core btusb snd_pcm videobuf2_vmalloc >> wmi_mof vfat dell_wmi fat videobuf2_memops btrtl btbcm btintel >> bluetooth dell_laptop dell_smbios dcdbas videobuf2_v4l2 snd_timer >> videobuf2_core rtsx_pci_ms snd irqbypass videodev memstick >> ghash_clmulni_intel joydev mei_me efi_pstore mei i2c_i801 soundcore >> efivars pcspkr idma64 shpchp virt_dma media rfkill intel_lpss_pci >> processor_thermal_device intel_soc_dts_iosf wmi acpi_als kfifo_buf >> int3403_thermal tpm_tis industrialio pinctrl_sunrisepoint tpm >> intel_hid int3400_thermal pinctrl_intel intel_lpss_acpi sparse_keymap >> int340x_thermal_zone acpi_thermal_rel intel_lpss nfsd acpi_pad >> auth_rpcgss nfs_acl lockd binfmt_misc grace sunrpc dm_crypt i915 >> i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt >> fb_sys_fops drm rtsx_pci_sdmmc >> [ 160.361548] mmc_core crct10dif_pclmul crc32_pclmul crc32c_intel >> rtsx_pci serio_raw i2c_hid video >> [ 160.361575] CPU: 2 PID: 2512 Comm: gnome-shell Not tainted >> 4.5.0-rc4-acpi+ #59 >> [ 160.361581] Hardware name: Dell Inc. XPS 13 9350/07TYC2, BIOS 1.1.9 >> 12/18/2015 >> [ 160.361588] 0000000000000086 00000000604232f7 ffff88024d55ba60 >> ffffffff81449d83 >> [ 160.361601] ffff88024d55baa8 ffffffffa01e15e8 ffff88024d55ba98 >> ffffffff81094252 >> [ 160.361612] ffff88026f4d0000 00000000000020a8 ffff88026f4d0000 >> 00000000fffffefe >> [ 160.361624] Call Trace: >> [ 160.361644] [<ffffffff81449d83>] dump_stack+0x65/0x92 >> [ 160.361660] [<ffffffff81094252>] warn_slowpath_common+0x82/0xc0 >> [ 160.361671] [<ffffffff810942ec>] warn_slowpath_fmt+0x5c/0x80 >> [ 160.361764] [<ffffffffa0158469>] hsw_unclaimed_reg_debug+0x69/0x90 [i915] >> [ 160.361844] [<ffffffffa015b71e>] gen9_write32+0x6e/0x390 [i915] >> [ 160.361855] [<ffffffff810b86a5>] ? preempt_count_add+0x85/0xd0 >> [ 160.361939] [<ffffffffa014d955>] gen8_logical_ring_get_irq+0x95/0xe0 >> [i915] >> [ 160.362017] [<ffffffffa013b4db>] __i915_wait_request+0x58b/0x650 [i915] >> [ 160.362028] [<ffffffff810d7380>] ? wake_atomic_t_function+0x70/0x70 >> [ 160.362113] [<ffffffffa013b70e>] >> i915_gem_object_wait_rendering__nonblocking+0x16e/0x2c0 [i915] >> [ 160.362200] [<ffffffffa0141c34>] ? i915_gem_pwrite_ioctl+0xe4/0x9b0 >> [i915] >> [ 160.362211] [<ffffffff810b86a5>] ? preempt_count_add+0x85/0xd0 >> [ 160.362225] [<ffffffff81857486>] ? _raw_write_unlock+0x16/0x30 >> [ 160.362312] [<ffffffffa013eed9>] i915_gem_set_domain_ioctl+0x99/0x160 >> [i915] >> [ 160.362357] [<ffffffffa00887c2>] drm_ioctl+0x152/0x540 [drm] >> [ 160.362439] [<ffffffffa013ee40>] ? >> i915_gem_object_set_to_gtt_domain+0x180/0x180 [i915] >> [ 160.362456] [<ffffffff813d30bd>] ? selinux_file_ioctl+0x11d/0x200 >> [ 160.362469] [<ffffffff81240521>] do_vfs_ioctl+0xa1/0x5b0 >> [ 160.362480] [<ffffffff81852c5d>] ? __schedule+0x3ad/0xa80 >> [ 160.362492] [<ffffffff81240aa9>] SyS_ioctl+0x79/0x90 >> [ 160.362505] [<ffffffff81857bae>] entry_SYSCALL_64_fastpath+0x12/0x71 >> [ 160.362515] ---[ end trace d66ecf0dd3c2adc4 ]--- >> [...] >> [ 249.526574] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] >> *ERROR* CPU pipe A FIFO underrun > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch -- Andy Lutomirski AMA Capital Management, LLC