This seems to happen sometimes when compiling Rust - possibly caused by rustc process? ``` $ crash_kernel_read Not already root, re-executing myself as root by using sudo(required!)... /usr/bin/makedumpfile is owned by makedumpfile 1.6.5-1 crash 7.2.6 Copyright (C) 2002-2019 Red Hat, Inc. Copyright (C) 2004, 2005, 2006, 2010 IBM Corporation Copyright (C) 1999-2006 Hewlett-Packard Co Copyright (C) 2005, 2006, 2011, 2012 Fujitsu Limited Copyright (C) 2006, 2007 VA Linux Systems Japan K.K. Copyright (C) 2005, 2011 NEC Corporation Copyright (C) 1999, 2002, 2007 Silicon Graphics, Inc. Copyright (C) 1999, 2000, 2001, 2002 Mission Critical Linux, Inc. This program is free software, covered by the GNU General Public License, and you are welcome to change it and/or distribute copies of it under certain conditions. Enter "help copying" to see the conditions. This program has absolutely no warranty. Enter "help warranty" for details. GNU gdb (GDB) 7.6 Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-unknown-linux-gnu"... WARNING: kernel relocated [720MB]: patching 75391 gdb minimal_symbol values KERNEL: /usr/lib/modules/5.1.7-g2f7d9d47575e/build/vmlinux DUMPFILE: /var/crash/crashdump-2019-06-08-09:08:23 [PARTIAL DUMP] CPUS: 6 DATE: Sat Jun 8 09:07:50 2019 UPTIME: 00:40:33 LOAD AVERAGE: 4.74, 5.80, 5.45 TASKS: 728 NODENAME: i87k RELEASE: 5.1.7-g2f7d9d47575e VERSION: #31 SMP Fri Jun 7 00:10:52 CEST 2019 MACHINE: x86_64 (3700 Mhz) MEMORY: 31.9 GB PANIC: "Oops: 0000 [#1] SMP PTI" (check log for details) PID: 25124 COMMAND: "rustc" TASK: ffff968413869e40 [THREAD_INFO: ffff968413869e40] CPU: 2 STATE: TASK_RUNNING (PANIC) crash> bt PID: 25124 TASK: ffff968413869e40 CPU: 2 COMMAND: "rustc" #0 [ffffb6eecf1a7660] machine_kexec at ffffffffae03400b #1 [ffffb6eecf1a76a8] __crash_kexec at ffffffffae124bd8 #2 [ffffb6eecf1a7770] crash_kexec at ffffffffae125a08 #3 [ffffb6eecf1a7788] oops_end at ffffffffae011866 #4 [ffffb6eecf1a77a8] no_context at ffffffffae03bdb7 #5 [ffffb6eecf1a7848] do_page_fault at ffffffffae03c7bb #6 [ffffb6eecf1a7870] page_fault at ffffffffae800dfe [exception RIP: compaction_alloc+1339] RIP: ffffffffae1b47eb RSP: ffffb6eecf1a7928 RFLAGS: 00010286 RAX: 0000000000000001 RBX: ffffb6eecf1a7b00 RCX: 0000000000000001 RDX: 80000000000ffe00 RSI: 0000000000000000 RDI: 000000000000003c RBP: 80000000000ffe00 R8: 0000000000000000 R9: 0000000000000034 R10: ffffe632c3ff8000 R11: ffffb6eecf1a7980 R12: 8000000000100000 R13: 0000000000000001 R14: ffffe632c3ff8000 R15: ffff96850dfded00 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 #7 [ffffb6eecf1a79c8] migrate_pages at ffffffffae1fa9a2 #8 [ffffb6eecf1a7a48] compact_zone at ffffffffae1b62f0 #9 [ffffb6eecf1a7ae8] compact_zone_order at ffffffffae1b67c3 #10 [ffffb6eecf1a7ba8] try_to_compact_pages at ffffffffae1b6fa4 #11 [ffffb6eecf1a7bf8] __alloc_pages_direct_compact at ffffffffae193f72 #12 [ffffb6eecf1a7c50] __alloc_pages_slowpath at ffffffffae1945f0 #13 [ffffb6eecf1a7d40] __alloc_pages_nodemask at ffffffffae194fa8 #14 [ffffb6eecf1a7da0] do_huge_pmd_anonymous_page at ffffffffae1fd37c #15 [ffffb6eecf1a7df0] __handle_mm_fault at ffffffffae1c0e0d #16 [ffffb6eecf1a7ea0] handle_mm_fault at ffffffffae1c152f #17 [ffffb6eecf1a7ec8] __do_page_fault at ffffffffae03c522 #18 [ffffb6eecf1a7f28] do_page_fault at ffffffffae03c7bb #19 [ffffb6eecf1a7f50] page_fault at ffffffffae800dfe RIP: 00007cd640afabbc RSP: 00007cd633fedc50 RFLAGS: 00010206 RAX: 00007cd5b02fe020 RBX: 00007cd602d01020 RCX: 00007cd5b00fe010 RDX: 00000000001fffff RSI: 0000000000d02000 RDI: 0000000000000010 RBP: 000000000000ffff R8: 0000000000000067 R9: 00007cd601fff010 R10: 0000000000000000 R11: 0000000000000246 R12: 00007cd5fd1f81b0 R13: 00007cd602d01020 R14: 00000000fffffdd2 R15: 00007cd601f67120 ORIG_RAX: ffffffffffffffff CS: 0033 SS: 002b crash> sys KERNEL: /usr/lib/modules/5.1.7-g2f7d9d47575e/build/vmlinux DUMPFILE: /var/crash/crashdump-2019-06-08-09:08:23 [PARTIAL DUMP] CPUS: 6 DATE: Sat Jun 8 09:07:50 2019 UPTIME: 00:40:33 LOAD AVERAGE: 4.74, 5.80, 5.45 TASKS: 728 NODENAME: i87k RELEASE: 5.1.7-g2f7d9d47575e VERSION: #31 SMP Fri Jun 7 00:10:52 CEST 2019 MACHINE: x86_64 (3700 Mhz) MEMORY: 31.9 GB PANIC: "Oops: 0000 [#1] SMP PTI" (check log for details) crash> bt PID: 25124 TASK: ffff968413869e40 CPU: 2 COMMAND: "rustc" #0 [ffffb6eecf1a7660] machine_kexec at ffffffffae03400b #1 [ffffb6eecf1a76a8] __crash_kexec at ffffffffae124bd8 #2 [ffffb6eecf1a7770] crash_kexec at ffffffffae125a08 #3 [ffffb6eecf1a7788] oops_end at ffffffffae011866 #4 [ffffb6eecf1a77a8] no_context at ffffffffae03bdb7 #5 [ffffb6eecf1a7848] do_page_fault at ffffffffae03c7bb #6 [ffffb6eecf1a7870] page_fault at ffffffffae800dfe [exception RIP: compaction_alloc+1339] RIP: ffffffffae1b47eb RSP: ffffb6eecf1a7928 RFLAGS: 00010286 RAX: 0000000000000001 RBX: ffffb6eecf1a7b00 RCX: 0000000000000001 RDX: 80000000000ffe00 RSI: 0000000000000000 RDI: 000000000000003c RBP: 80000000000ffe00 R8: 0000000000000000 R9: 0000000000000034 R10: ffffe632c3ff8000 R11: ffffb6eecf1a7980 R12: 8000000000100000 R13: 0000000000000001 R14: ffffe632c3ff8000 R15: ffff96850dfded00 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 #7 [ffffb6eecf1a79c8] migrate_pages at ffffffffae1fa9a2 #8 [ffffb6eecf1a7a48] compact_zone at ffffffffae1b62f0 #9 [ffffb6eecf1a7ae8] compact_zone_order at ffffffffae1b67c3 #10 [ffffb6eecf1a7ba8] try_to_compact_pages at ffffffffae1b6fa4 #11 [ffffb6eecf1a7bf8] __alloc_pages_direct_compact at ffffffffae193f72 #12 [ffffb6eecf1a7c50] __alloc_pages_slowpath at ffffffffae1945f0 #13 [ffffb6eecf1a7d40] __alloc_pages_nodemask at ffffffffae194fa8 #14 [ffffb6eecf1a7da0] do_huge_pmd_anonymous_page at ffffffffae1fd37c #15 [ffffb6eecf1a7df0] __handle_mm_fault at ffffffffae1c0e0d #16 [ffffb6eecf1a7ea0] handle_mm_fault at ffffffffae1c152f #17 [ffffb6eecf1a7ec8] __do_page_fault at ffffffffae03c522 #18 [ffffb6eecf1a7f28] do_page_fault at ffffffffae03c7bb #19 [ffffb6eecf1a7f50] page_fault at ffffffffae800dfe RIP: 00007cd640afabbc RSP: 00007cd633fedc50 RFLAGS: 00010206 RAX: 00007cd5b02fe020 RBX: 00007cd602d01020 RCX: 00007cd5b00fe010 RDX: 00000000001fffff RSI: 0000000000d02000 RDI: 0000000000000010 RBP: 000000000000ffff R8: 0000000000000067 R9: 00007cd601fff010 R10: 0000000000000000 R11: 0000000000000246 R12: 00007cd5fd1f81b0 R13: 00007cd602d01020 R14: 00000000fffffdd2 R15: 00007cd601f67120 ORIG_RAX: ffffffffffffffff CS: 0033 SS: 002b crash> log [ 0.000000] microcode: microcode updated early to revision 0xb4, date = 2019-04-01 [ 0.000000] Linux version 5.1.7-g2f7d9d47575e (user@i87k) (gcc version 8.3.0 (GCC)) #31 SMP Fri Jun 7 00:10:52 CEST 2019 [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-linux-stable root=UUID=2b8b9ab8-7ac5-4586-aa42-d7ffb12de92a rw root_trim=yes rd.luks.allow-discards rd.luks.options=discard ipv6.disable=1 ipv6.disable_ipv6=1 ipv6.autoconf=0 loglevel=15 log_buf_len=16M ignore_loglevel printk.always_kmsg_dump=y printk.time=y printk.devkmsg=on mminit_loglevel=4 memory_corruption_check=1 fbcon=scrollback:4096k fbcon=font:ProFont6x11 net.ifnames=0 nolvm dobtrfs console=tty1 earlyprintk=vga audit=0 systemd.log_target=kmsg systemd.journald.forward_to_console=1 enforcing=0 udev.children-max=1256 rd.udev.children-max=1256 nohz=on oops=panic crashkernel=256M panic=0 psi=1 sysrq_always_enabled random.trust_cpu=off logo.nologo lpj=0 mce=bootlog reboot=force,cold noexec=on nohibernate scsi_mod.use_blk_mq=1 consoleblank=120 mitigations=auto,nosmt l1tf=full,force spec_store_bypass_disable=auto spectre_v2=auto spectre_v2_user=auto mds=full,nosmt rd.log=all noefi cpuidle.governor=teo zram.num_devices=3 zswap.enabled=0 ... ...skipping... [ 2389.133343] i2c i2c-2: NAK from device addr 0x50 msg #0 [ 2389.137459] i2c i2c-1: NAK from device addr 0x50 msg #0 [ 2389.141642] i2c i2c-3: NAK from device addr 0x50 msg #0 [ 2432.660116] gpg-agent[1125]: handler 0x74e5c195d700 for fd 10 started [ 2432.730809] gpg-agent[1125]: handler 0x74e5c195d700 for fd 10 terminated [ 2434.126414] BUGGY: unable to handle kernel paging request at ffffe632c3ff8030 [ 2434.126415] #PF error: [normal kernel read fault] [ 2434.126416] PGD 82dfd5067 P4D 82dfd5067 PUD 82dfd4067 PMD 0 [ 2434.126418] Oops: 0000 [#1] SMP PTI [ 2434.126419] CPU: 2 PID: 25124 Comm: rustc Kdump: loaded Tainted: G U 5.1.7-g2f7d9d47575e #31 [ 2434.126420] Hardware name: System manufacturer System Product Name/PRIME Z370-A, BIOS 1002 07/02/2018 [ 2434.126422] RIP: 0010:compaction_alloc+0x53b/0x890 [ 2434.126423] Code: 1f 41 83 c5 01 4c 39 f5 0f 82 5e 01 00 00 4c 89 34 24 eb 76 49 89 ea 49 c1 e2 06 4c 03 15 75 f3 d0 00 4d 89 d6 4d 85 f6 74 44 <41> 8b 46 30 25 80 00 00 f0 3d 00 00 00 f0 0f 84 ff 00 00 00 80 7b [ 2434.126423] RSP: 0000:ffffb6eecf1a7928 EFLAGS: 00010286 [ 2434.126424] RAX: 0000000000000001 RBX: ffffb6eecf1a7b00 RCX: 0000000000000001 [ 2434.126425] RDX: 80000000000ffe00 RSI: 0000000000000000 RDI: 000000000000003c [ 2434.126425] RBP: 80000000000ffe00 R08: 0000000000000000 R09: 0000000000000034 [ 2434.126426] R10: ffffe632c3ff8000 R11: ffffb6eecf1a7980 R12: 8000000000100000 [ 2434.126426] R13: 0000000000000001 R14: ffffe632c3ff8000 R15: ffff96850dfded00 [ 2434.126427] FS: 00007cd633fff700(0000) GS:ffff9684eda80000(0000) knlGS:0000000000000000 [ 2434.126428] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2434.126428] CR2: ffffe632c3ff8030 CR3: 00000007ae5a8005 CR4: 00000000003606e0 [ 2434.126429] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 2434.126429] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 2434.126430] Call Trace: [ 2434.126432] migrate_pages+0x112/0xa00 [ 2434.126433] ? isolate_freepages_block+0x330/0x330 [ 2434.126434] ? move_freelist_tail+0xd0/0xd0 [ 2434.126435] compact_zone+0x6b0/0xab0 [ 2434.126436] compact_zone_order+0xd3/0x110 [ 2434.126437] ? psi_task_change+0xe2/0x210 [ 2434.126438] try_to_compact_pages+0x164/0x220 [ 2434.126439] __alloc_pages_direct_compact+0x82/0x170 [ 2434.126440] __alloc_pages_slowpath+0x430/0xb70 [ 2434.126441] __alloc_pages_nodemask+0x278/0x2c0 [ 2434.126442] do_huge_pmd_anonymous_page+0x12c/0x5e0 [ 2434.126444] __handle_mm_fault+0xbed/0x1250 [ 2434.126445] handle_mm_fault+0xbf/0x1e0 [ 2434.126446] __do_page_fault+0x242/0x490 [ 2434.126448] ? page_fault+0x8/0x30 [ 2434.126449] do_page_fault+0x1b/0x5e [ 2434.126449] page_fault+0x1e/0x30 [ 2434.126450] RIP: 0033:0x7cd640afabbc [ 2434.126451] Code: 74 dc 41 f7 d6 eb 31 49 c1 e8 39 48 8d 46 f0 48 21 d0 44 88 04 31 44 88 44 01 10 48 8b 44 24 40 48 c1 e6 05 c4 c1 7e 6f 45 00 <c5> fe 7f 04 30 4c 89 cd 66 45 85 f6 74 a6 48 8b 7c 24 60 c5 f8 77 [ 2434.126452] RSP: 002b:00007cd633fedc50 EFLAGS: 00010206 [ 2434.126452] RAX: 00007cd5b02fe020 RBX: 00007cd602d01020 RCX: 00007cd5b00fe010 [ 2434.126453] RDX: 00000000001fffff RSI: 0000000000d02000 RDI: 0000000000000010 [ 2434.126453] RBP: 000000000000ffff R08: 0000000000000067 R09: 00007cd601fff010 [ 2434.126454] R10: 0000000000000000 R11: 0000000000000246 R12: 00007cd5fd1f81b0 [ 2434.126454] R13: 00007cd602d01020 R14: 00000000fffffdd2 R15: 00007cd601f67120 [ 2434.126455] Modules linked in: xt_comment msr xt_TCPMSS iptable_mangle iptable_security iptable_nat nf_nat iptable_raw nf_log_ipv4 nf_log_common xt_owner xt_LOG xt_connlimit nf_conncount xt_conntrack nf_conntrack nf_defrag_ipv4 xt_hashlimit xt_multiport xt_addrtype snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp i915 crct10dif_pclmul crc32_pclmul crc32c_intel i2c_algo_bit drm_kms_helper snd_hda_intel snd_hda_codec syscopyarea sysfillrect sysimgblt ghash_clmulni_intel snd_hwdep fb_sys_fops iTCO_wdt intel_cstate snd_hda_core drm iTCO_vendor_support intel_uncore snd_pcm intel_rapl_perf snd_timer pcspkr mei_me mq_deadline snd drm_panel_orientation_quirks e1000e soundcore i2c_i801 mei xhci_pci xhci_hcd [ 2434.126466] CR2: ffffe632c3ff8030 ``` I have the crash dump so i can run other commands if more info is wanted. Please let me know. I'm on ArchLinux. ``` $ lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 39 bits physical, 48 bits virtual CPU(s): 6 On-line CPU(s) list: 0-5 Thread(s) per core: 1 Core(s) per socket: 6 Socket(s): 1 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 158 Model name: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz Stepping: 10 CPU MHz: 800.016 CPU max MHz: 4700.0000 CPU min MHz: 800.0000 BogoMIPS: 7392.00 Virtualization: VT-x L1d cache: 192 KiB L1i cache: 192 KiB L2 cache: 1.5 MiB L3 cache: 12 MiB NUMA node0 CPU(s): 0-5 Vulnerability L1tf: Mitigation; PTE Inversion Vulnerability Mds: Mitigation; Clear CPU buffers; SMT disabled Vulnerability Meltdown: Mitigation; PTI Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp Vulnerability Spectre v1: Mitigation; __user pointer sanitization Vulnerability Spectre v2: Mitigation; Full generic retpoline, IBPB conditional, IBRS_FW, RSB filling Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pd pe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmul qdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp md_clear flush_l1d ```
Initially hit and documented here: https://gist.github.com/howaboutsynergy/c69f4a44ad10f7cce48c1544266e43f6 and here:https://bugzilla.kernel.org/show_bug.cgi?id=203735 but I didn't have crash dump then so I thought it was caused by something else! The patches that I had in kernel are listed(ie. their file names) here: https://github.com/howaboutsynergy/q1q/blob/fb691dfbf4d56065bcee061d25d90ccf498485ed/OSes/archlinux/home/user/build/1packages/4used/kernel/linuxgit/PKGBUILD#L80-L148 (and located in the same dir as that PKGBUILD) But the following PKGBUILD was used (because this was linux-stable kernel 5.1.7, based on PKGBUILD/patches files for the linuxgit mentioned above): https://github.com/howaboutsynergy/q1q/blob/fb691dfbf4d56065bcee061d25d90ccf498485ed/OSes/archlinux/home/user/build/1packages/4used/kernel/linux-stable/PKGBUILD
This issue was likely present since at least kernel [5.1.5-g835365932f0d](https://gist.github.com/howaboutsynergy/c69f4a44ad10f7cce48c1544266e43f6#gistcomment-2927872) (assuming the same crash happened the first time I've encountered this issue when I didn't have ability to get crash dump; the current crash, in OP, being the second time it happened since around 10May2019 when I've installed archlinux on this system)
Created attachment 283151 [details] .config
that was .config used for kernel 5.1.7 (got via zcat /proc/config.gz) looks like there was some leftover like CONFIG_BUILD_SALT="4.19.15-300.fc29.x86_64" because I "imported" it from Qubes OS Fedora 29 a while ago.
I wonder if this fixes it: ``` commit e577c8b64d58fe307ea4d5149d31615df2d90861 Date: Fri May 31 22:30:59 2019 -0700 ``` aka https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e577c8b64d58fe307ea4d5149d31615df2d90861 because I did not have that commit in [5.1.7](https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tag/?h=v5.1.7)
I have swap enabled, in zram: ``` $ swapon NAME TYPE SIZE USED PRIO /dev/zram0 partition 64G 0B -2 $ swapon -s Filename Type Size Used Priority /dev/zram0 partition 67108860 0 -2 $ zramctl /dev/zram0 NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT /dev/zram0 zstd 64G 4K 63B 4K 6 [SWAP] ``` I'm going to apply that patch on top of 5.1.7 ... since it's so simple: ```patch diff --git a/mm/compaction.c b/mm/compaction.c index 9febc8cc84e7..9e1b9acb116b 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1399,7 +1399,7 @@ fast_isolate_freepages(struct compact_control *cc) page = pfn_to_page(highest); cc->free_pfn = highest; } else { - if (cc->direct_compaction) { + if (cc->direct_compaction && pfn_valid(min_pfn)) { page = pfn_to_page(min_pfn); cc->free_pfn = min_pfn; } ```
ok something is messed up on bugzilla, the above two comments are definitely not what I posted, their contents got messed up! what teh!!!!
made https://bugzilla.mozilla.org/show_bug.cgi?id=1557932 about that.
crash> sym ffffffffae1b47eb ffffffffae1b47eb (t) compaction_alloc+1339 /home/user/build/1packages/4used/kernel/linux-stable/makepkg_pacman/linux-stable/src/linux-stable/./include/linux/page-flags.h: 735 shows it's this line: /* * PageBuddy() indicates that the page is free and in the buddy system * (see mm/page_alloc.c). */ PAGE_TYPE_OPS(Buddy, buddy) //this line Anyway, I applied patch mentioned in Comment 5 and if this happens again I'll update.
recompiling kernel with changed CONFIG_PAGE_POISONING_ZERO=y to =n maybe that would help?!?? and added `page_poison=1` to /proc/cmdline Note that I'm still able to execute `crash` commands on the crashdump due to having saved the debugging kernel image(and all other stuff even) so if anyone wanted more info related to the OP crash, just ask.
I'm switching to kernel [5.1.8](https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tag/?h=v5.1.8) just got released 7mins ago
I'm switching to [5.1.9](https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tag/?h=v5.1.9) which was released 3 hours ago. since the prev. comment, I've tried recompiling rustc multiple times, almost for fun, but the issue didn't trigger yet.... assuming it didn't already get fixed by [commit](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e577c8b64d58fe307ea4d5149d31615df2d90861) which was present since 5.1.8 But then again it did take 7 days to trigger again(for the second time) last time (since kernel 5.1.5, to 5.1.7) so this might be why: it's not easy to hit it.
hey now, I've just looked at log for stable kernel 5.1.y branch for `mm/compaction.c`: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/log/mm/compaction.c?h=linux-5.1.y compared to the same log for the git kernel: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/mm/compaction.c and I notice that at least one commit isn't present in that stable kernel: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/mm/compaction.c?id=dd7ef7bd14640f11763b54f55131000165f48321 so how am I to know it isn't already fixed in git kernel, but still not yet fixed in the stable kernel ? oh well, ignorance is bliss :D
On Tue, Jun 11, 2019 at 01:59:47PM +0000, bugzilla-daemon@bugzilla.kernel.org wrote: > and I notice that at least one commit isn't present in that stable kernel: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/mm/compaction.c?id=dd7ef7bd14640f11763b54f55131000165f48321 > > so how am I to know it isn't already fixed in git kernel, but still not yet > fixed in the stable kernel ? > > oh well, ignorance is bliss :D > Don't worry about that one. It's warning that the shift may not have meaning because the shift value is too large. However, in this specific case, the result is 0 which is valid behaviour for this code path. The warning is meant to catch things like a large type being accidentally cast to a small type and shifted by a large value. The consequences can be that the upper bits are unexpectedly lost. In this particular code path, we don't care. It's a cosmetic fix for the most part, no functional impact.
Thanks! That commit is in [5.1.10](https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tag/?h=v5.1.10), released 6 hours ago, I'm switching to it in a few mins!
ok I'm closing this, will reopen if it really happens again. Meanwhile I'll keep switching to latest kernel stable (5.1.11 released 85mins ago) I'm assuming it got fixed by this a while ago: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e577c8b64d58fe307ea4d5149d31615df2d90861