| Message ID | 604a92ae-cbbb-7c34-f9aa-f7c08925bedf@lca.pw (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | low-memory crash with patch "capture a page under direct compaction" | expand |
On Mon, Mar 04, 2019 at 10:55:04PM -0500, Qian Cai wrote: > Reverted the patches below from linux-next seems fixed a crash while running LTP > oom01. > > 915c005358c1 mm, compaction: Capture a page under direct compaction -fix > e492a5711b67 mm, compaction: capture a page under direct compaction > > Especially, just removed this chunk along seems fixed the problem. > > --- a/mm/compaction.c > +++ b/mm/compaction.c > @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct > capture_control *capc) > } > > /* Stop if a page has been captured */ > - if (capc && capc->page) { > - ret = COMPACT_SUCCESS; > - break; > - } > It's hard to make sense of how this is connected to the bug. The out-of-bounds warning would have required page flags to be corrupted quite badly or maybe the use of an uninitialised page. How reproducible has this been for you? I just ran the test 100 times with UBSAN and page alloc debugging enabled and it completed correctly.
On Tue, 2019-03-05 at 14:42 +0000, Mel Gorman wrote: > On Mon, Mar 04, 2019 at 10:55:04PM -0500, Qian Cai wrote: > > Reverted the patches below from linux-next seems fixed a crash while running > > LTP > > oom01. > > > > 915c005358c1 mm, compaction: Capture a page under direct compaction -fix > > e492a5711b67 mm, compaction: capture a page under direct compaction > > > > Especially, just removed this chunk along seems fixed the problem. > > > > --- a/mm/compaction.c > > +++ b/mm/compaction.c > > @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct > > capture_control *capc) > > } > > > > /* Stop if a page has been captured */ > > - if (capc && capc->page) { > > - ret = COMPACT_SUCCESS; > > - break; > > - } > > > > It's hard to make sense of how this is connected to the bug. The > out-of-bounds warning would have required page flags to be corrupted > quite badly or maybe the use of an uninitialised page. How reproducible > has this been for you? I just ran the test 100 times with UBSAN and page > alloc debugging enabled and it completed correctly. > I did manage to reproduce this every time by running oom01 within 3 tries on this x86_64 server and was unable to reproduce on arm64 and ppc64le servers so far. # for i in `seq 1 3`; do /opt/ltp/testcases/bin/oom01 ; done Sometimes, it could trigger different traces. [ 391.704320] SLUB: Unable to allocate memory on node -1, gfp=0x800(GFP_NOWAIT) [ 391.737794] cache: kmalloc-64, object size: 64, buffer size: 416, default order: 2, min order: 0 [ 391.778079] node 0: slabs: 5999, objs: 232851, free: 16 [ 391.802926] node 1: slabs: 4303, objs: 167067, free: 37 [ 499.866479] ------------[ cut here ]------------ [ 499.866500] BUG: Bad page state in process oom01 pfn:fffffe7a09fffd07 [ 499.890013] kernel BUG at mm/page_alloc.c:3124! [ 499.935430] double fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 499.971334] CPU: 0 PID: 1623 Comm: oom01 Tainted: G W 5.0.0-next-20190305+ #49 [ 499.992805] ================================================================================ [ 500.009887] Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 [ 500.009901] RIP: 0010:check_memory_region+0x10/0x1e0 [ 500.048252] UBSAN: Undefined behaviour in kernel/locking/qspinlock.c:138:9 [ 500.085378] Code: 00 00 00 48 89 e5 e8 ff 3e 9f 00 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 48 85 f6 0f 84 68 01 00 00 55 0f b6 d2 48 89 e5 <41> 55 41 54 53 e9 b3 00 00 00 48 b8 00 00 00 00 00 00 00 ff 48 39 [ 500.107608] index 8190 is out of range for type 'long unsigned int [256]' [ 500.138462] RSP: 0000:ffff888428f80000 EFLAGS: 00010002 [ 500.223186] CPU: 42 PID: 0 Comm: swapper/42 Tainted: G W 5.0.0-next-20190305+ #49 [ 500.253922] RAX: ffff88827fff41c0 RBX: ffff88827fff41c8 RCX: ffffffff9c0a9468 [ 500.253925] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88827fff41f8 [ 500.277367] Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 [ 500.277370] Call Trace: [ 500.318081] RBP: ffff888428f80000 R08: ffffed104fffe840 R09: ffffed104fffe83f [ 500.318085] R10: ffffed104fffe83f R11: ffff88827fff41fb R12: ffff88827fff41f8 [ 500.349838] <IRQ> [ 500.381765] R13: ffff88827fff41c8 R14: ffff88842a96f770 R15: ffff88827fff41c8 [ 500.381768] FS: 00007fdfd3559700(0000) GS:ffff8881f3c00000(0000) knlGS:0000000000000000 [ 500.424074] dump_stack+0x62/0x9a [ 500.435452] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 500.435455] CR2: ffff888428f7fff8 CR3: 000000041abca003 CR4: 00000000001606b0 [ 500.467546] ubsan_epilogue+0xd/0x7f [ 500.500039] Call Trace: [ 500.500042] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat kvm_intel kvm irqbypass efivars ip_tables x_tables xfs sd_mod ahci igb libahci i2c_algo_bit i2c_core libata dm_mirror dm_region_hash dm_log dm_mod efivarfs [ 500.509058] __ubsan_handle_out_of_bounds+0x14d/0x192 [ 500.541152] ---[ end trace f9ff2b89b6b88c5f ]--- [ 500.541155] invalid opcode: 0000 [#2] SMP DEBUG_PAGEALLOC KASAN PTI [ 500.541159] CPU: 10 PID: 262 Comm: kcompactd0 Tainted: G D W 5.0.0-next-20190305+ #49 [ 500.541161] Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 [ 500.541167] RIP: 0010:__isolate_free_page+0x464/0x600 [ 500.541170] Code: 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c7 c6 20 6f 0b 9d 48 89 df e8 4a 8b f8 ff 0f 0b 48 c7 c7 a0 32 69 9d e8 51 40 43 00 <0f> 0b 48 c7 c7 e0 31 69 9d e8 43 40 43 00 48 c7 c6 80 71 0b 9d 48 [ 500.541172] RSP: 0000:ffff8881f1fdf848 EFLAGS: 00010002 [ 500.541175] RAX: 00000000f0000080 RBX: ffffea00064fc000 RCX: ffff88827fff41d0 [ 500.541177] RDX: 1ffffd4000c9f806 RSI: 0000000000000008 RDI: ffffffff9d9f1640 [ 500.541179] RBP: ffff8881f1fdf898 R08: ffffea00064fc000 R09: ffff8881f1fdfd30 [ 500.541181] R10: 0000000000000002 R11: 1ffff1104fffe83b R12: 0000000000000008 [ 500.541183] R13: dffffc0000000000 R14: ffff88827fff3000 R15: 0000000000000002 [ 500.541185] FS: 0000000000000000(0000) GS:ffff8881f4100000(0000) knlGS:0000000000000000 [ 500.541188] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 500.541190] CR2: 00007fdce416a000 CR3: 000000026ea16002 CR4: 00000000001606a0 [ 500.541191] Call Trace: [ 500.541199] compaction_alloc+0x886/0x25f0 [ 500.541221] unmap_and_move+0x37/0x1e70 [ 500.541228] migrate_pages+0x2ca/0xb20 [ 500.541238] compact_zone+0x19cb/0x3620 [ 500.541252] kcompactd_do_work+0x2df/0x680
On Tue, Mar 05, 2019 at 10:13:24AM -0500, Qian Cai wrote: > On Tue, 2019-03-05 at 14:42 +0000, Mel Gorman wrote: > > On Mon, Mar 04, 2019 at 10:55:04PM -0500, Qian Cai wrote: > > > Reverted the patches below from linux-next seems fixed a crash while running > > > LTP > > > oom01. > > > > > > 915c005358c1 mm, compaction: Capture a page under direct compaction -fix > > > e492a5711b67 mm, compaction: capture a page under direct compaction > > > > > > Especially, just removed this chunk along seems fixed the problem. > > > > > > --- a/mm/compaction.c > > > +++ b/mm/compaction.c > > > @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct > > > capture_control *capc) > > > } > > > > > > /* Stop if a page has been captured */ > > > - if (capc && capc->page) { > > > - ret = COMPACT_SUCCESS; > > > - break; > > > - } > > > > > > > It's hard to make sense of how this is connected to the bug. The > > out-of-bounds warning would have required page flags to be corrupted > > quite badly or maybe the use of an uninitialised page. How reproducible > > has this been for you? I just ran the test 100 times with UBSAN and page > > alloc debugging enabled and it completed correctly. > > > > I did manage to reproduce this every time by running oom01 within 3 tries on > this x86_64 server and was unable to reproduce on arm64 and ppc64le servers so > far. > Ok, so there is something specific about the machine or the kernel config that is at play. You're seeing slub issues, page state issues etc. Have you seen this on any other x86-based machine? Also please post your kernel config. Are you certain that removing the block from your first email avoids any issue triggering?
On Tue, 2019-03-05 at 15:27 +0000, Mel Gorman wrote: > > On Tue, Mar 05, 2019 at 10:13:24AM -0500, Qian Cai wrote: >> > > On Tue, 2019-03-05 at 14:42 +0000, Mel Gorman wrote: >>> > > > On Mon, Mar 04, 2019 at 10:55:04PM -0500, Qian Cai wrote: >>>> > > > > Reverted the patches below from linux-next seems fixed a crash while> >>>> > > > running >>>> > > > > LTP >>>> > > > > oom01. >>>> > > > > >>>> > > > > 915c005358c1 mm, compaction: Capture a page under direct compaction -fix >>>> > > > > e492a5711b67 mm, compaction: capture a page under direct compaction >>>> > > > > >>>> > > > > Especially, just removed this chunk along seems fixed the problem. >>>> > > > > >>>> > > > > --- a/mm/compaction.c >>>> > > > > +++ b/mm/compaction.c >>>> > > > > @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct >>>> > > > > capture_control *capc) >>>> > > > > } >>>> > > > > >>>> > > > > /* Stop if a page has been captured */ >>>> > > > > - if (capc && capc->page) { >>>> > > > > - ret = COMPACT_SUCCESS; >>>> > > > > - break; >>>> > > > > - } >>>> > > > > >>> > > > >>> > > > It's hard to make sense of how this is connected to the bug. The >>> > > > out-of-bounds warning would have required page flags to be corrupted >>> > > > quite badly or maybe the use of an uninitialised page. How reproducible >>> > > > has this been for you? I just ran the test 100 times with UBSAN and page >>> > > > alloc debugging enabled and it completed correctly. >>> > > > Well, 100 times would take a long time to run with swapping enabled. BTW, if you are running the tests without a swap device, I just confirmed (tried 10 times) that it won't trigger it. It seems needing kswapd to play. >> > > >> > > I did manage to reproduce this every time by running oom01 within 3 tries on >> > > this x86_64 server and was unable to reproduce on arm64 and ppc64le >> servers> > so >> > > far. >> > > > > > > Ok, so there is something specific about the machine or the kernel > > config that is at play. You're seeing slub issues, page state issues > > etc. Have you seen this on any other x86-based machine? Also please post I have only one NUMA x86_64 server to test. Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 48 On-line CPU(s) list: 0-47 Thread(s) per core: 2 Core(s) per socket: 12 Socket(s): 2 NUMA node(s): 2 Vendor ID: GenuineIntel CPU family: 6 Model: 63 Model name: Intel(R) Xeon(R) CPU E5-2650L v3 @ 1.80GHz Stepping: 2 CPU MHz: 2097.552 BogoMIPS: 3595.80 Virtualization: VT-x L1d cache: 32K L1i cache: 32K L2 cache: 256K L3 cache: 30720K NUMA node0 CPU(s): 0-11,24-35 NUMA node1 CPU(s): 12-23,36-47 > > your kernel config. Are you certain that removing the block from your https://git.sr.ht/~cai/linux-debug/tree/master/config > > first email avoids any issue triggering? > > No, I tried again on the latest linux-next, and could trigger a memory corruption below immediately with only that chunk of code removed. However, I am still trigger NONE of these after reverted the above two commits. This has been tested more than 10 times so far. I don't understand this part. @@ -2279,14 +2286,24 @@ static enum compact_result compact_zone_order(struct zone *zone, int order, .ignore_skip_hint = (prio == MIN_COMPACT_PRIORITY), .ignore_block_suitable = (prio == MIN_COMPACT_PRIORITY) }; + struct capture_control capc = { + .cc = &cc, + .page = NULL, + }; + + if (capture) + current->capture_control = &capc; That check will always be true as it is, struct page **capture; *capture could be NULL, but not capture because in __alloc_pages_direct_compact(), it does, struct page *page = NULL; [ 1337.354171] Tasks state (memory values in pages): [ 1337.376691] [ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name [ 1337.415473] [ 842] 0 842 26405 18 212992 422 -1000 systemd-udevd [ 1337.455205] [ 1120] 0 1120 25103 44 94208 44 0 irqbalance [ 1337.496195] [ 1121] 0 1121 46184 9 368640 387 0 sssd [ 1337.534072] [ 1122] 0 1122 95328 0 245760 758 0 rngd [ 1337.570370] [ 1124] 81 1124 18353 104 167936 88 -900 dbus-daemon [ 1337.609494] [ 1125] 0 1125 97658 58 385024 545 0 NetworkManager [ 1337.649637] [ 1126] 998 1126 1325451 0 729088 2515 0 polkitd [ 1337.687137] [ 1134] 995 1134 7359 6 90112 68 0 chronyd [ 1337.724754] [ 1144] 0 1144 47800 17 385024 505 0 sssd_be [ 1337.762143] [ 1203] 0 1203 23592 22 208896 201 -1000 sshd [ 1337.798337] [ 1217] 0 1217 3780 0 69632 46 0 rhsmcertd [ 1337.837743] [ 1242] 0 1242 50092 66 417792 247 0 sssd_nss [ 1337.875687] [ 1254] 0 1254 23884 42 196608 204 0 systemd-logind [ 1337.915916] [ 1263] 0 1263 23263 1 221184 346 0 systemd [ 1337.953124] [ 1264] 0 1264 3917 0 65536 36 0 agetty [ 1337.991199] [ 1265] 0 1265 3275 0 69632 32 0 agetty [ 1338.031884] [ 1268] 0 1268 37093 0 307200 756 0 (sd-pam) [ 1338.071161] [ 1431] 0 1431 56279 135 192512 314 0 rsyslogd [ 1338.110818] [ 1467] 0 1467 37779 0 303104 293 0 sshd [ 1338.147561] [ 1477] 0 1477 9022 13 106496 207 0 crond [ 1338.184215] [ 1510] 0 1510 2424 0 65536 85 0 make [ 1338.220461] [ 1514] 0 1514 6312 39 90112 62 0 runtest.sh [ 1338.260766] [ 1530] 0 1530 37779 5 294912 289 0 sshd [ 1338.297301] [ 1537] 0 1537 6344 25 90112 138 0 bash [ 1338.333662] [ 1815] 0 1815 22774 849 196608 0 0 systemd-journal [ 1338.375669] [ 1822] 0 1822 2184 1 65536 21 0 oom01 [ 1338.413577] [ 1823] 0 1823 2184 6 65536 25 0 oom01 [ 1338.451815] [ 1831] 0 1831 37060791 3004590 40919040 2037460 0 oom01 [ 1338.490312] [ 1882] 0 1882 18868 96 184320 0 0 sshd [ 1338.530810] [ 1884] 0 1884 6312 40 65536 61 0 runtest.sh [ 1338.570643] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0-1,global_oom,task_memcg=/user.slice,task=oom01,pid=1831,uid=0 [ 1338.630662] Out of memory: Killed process 1831 (oom01) total-vm:148243164kB, anon-rss:12018360kB, file-rss:0kB, shmem-rss:0kB [ 1338.871046] pagealloc: memory corruption [ 1338.888610] 00000000fe6aab78: 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1338.927858] 000000000e5b758b: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1338.967042] 000000007be27dd4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.006041] 00000000adc52ca0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.049599] 000000001b14ef55: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.088801] 0000000085aaa5be: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.127998] 00000000bff7bf43: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.170213] 0000000021489d04: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.212549] 000000000830d1fc: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.253430] 000000009e7738ad: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.294248] 000000006ceefc4b: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.335126] 000000003c957eb9: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.376173] 000000007e1a9b3c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.416998] 000000008360db50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.457628] 000000004382d7a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.498205] 000000005c7468cf: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.539740] 0000000007128978: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.583374] 00000000ef6a7c8d: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.624196] 00000000fdb1a596: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.665038] 000000009d2b4871: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.705904] 00000000f64101ae: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.746724] 000000005932f1c3: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.787103] 000000006f387d61: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.827995] 00000000b4e9bac0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.868804] 000000003a67e0cc: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.909348] 00000000d1b415d7: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.950163] 000000006696703f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1339.990887] 000000007236a552: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.031484] 00000000ced67fc2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.074633] 00000000eacb00b5: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.115769] 00000000cd762b0f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.156785] 000000002c5bed3a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.197483] 00000000df97bd05: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.237216] 000000006c8bcd34: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.277982] 0000000056769a33: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.318833] 00000000b3a8b011: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.359718] 00000000fb93777f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.400749] 00000000ed72f51b: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.441546] 000000000f0a9c06: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.483011] 0000000058acc3cd: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.523274] 00000000b4d019be: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.564549] 000000009f8786cc: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.607931] 00000000df5ef2ee: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.648340] 00000000702ccf47: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.688788] 0000000099b19e48: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.729510] 0000000039f02ec9: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.770114] 0000000083addea3: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.810756] 0000000037edee75: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.851188] 000000000e4c2e2d: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.891941] 000000008d149b07: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.932548] 00000000909f66ff: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1340.974102] 0000000081df28c7: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.014377] 00000000b84b7870: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.057578] 0000000010b3382a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.101431] 0000000057ffa361: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.142096] 0000000038a61326: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.183669] 000000006587b87c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.225377] 00000000ef60f1bf: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.267021] 00000000c744bb03: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.307789] 0000000044b4fdb1: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.348610] 00000000531f189e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.389665] 000000001b8a4714: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.433146] 000000004bffa794: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.473933] 000000009f2b6148: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.514885] 0000000042c62fd1: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.555589] 0000000059c01744: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.597952] 00000000478c3d29: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.639360] 000000000eea2248: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.679780] 00000000c5ed98a7: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.720502] 0000000074bbce1d: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.761500] 0000000097880cb2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.802288] 000000008b79b1fb: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.843276] 00000000defe452a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.884060] 00000000bde4c4b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.924744] 000000008e846c70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1341.965668] 000000007336d83e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.006371] 00000000eb55a3a2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.047310] 00000000b1c967a3: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.089204] 00000000d2f1e1d9: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.133340] 0000000028b653d5: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.173945] 0000000049ee0f29: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.214806] 000000009444ab05: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.255680] 0000000023df52aa: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.296482] 000000001f3595e2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.335955] 00000000f6b3d57b: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.376908] 000000002d4fb3ee: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.417942] 000000002c32aaa8: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.458733] 000000000f7db7b7: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.497855] 000000008f107ca2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.537396] 00000000ab15fa75: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.577357] 000000004f3e42cc: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.620410] 00000000ddcdfc4b: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.661380] 00000000006f449e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.702263] 00000000ed65b70a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.743280] 00000000904810ad: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.783915] 000000004fab9e3c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.824915] 000000002b2c24c2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.865700] 000000006240fcfd: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.906510] 00000000257e52b5: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.947344] 00000000157a76e2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1342.988142] 000000005475a4da: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.028494] 0000000069a7362e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.069200] 000000004ac4c37a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.111084] 00000000d941b898: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.153683] 00000000cf25dfd6: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.194468] 000000002d010c45: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.235185] 000000001f8523c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.276074] 0000000026283d91: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.316850] 00000000f8dc3d4c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.357643] 00000000de3d6424: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.398590] 00000000ed7571c6: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.439336] 000000000c87eccd: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.480140] 000000007610d962: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.520697] 000000008f8e1aa2: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.561460] 00000000fd77596e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.602090] 00000000389c7804: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.646002] 000000004737fa15: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.687710] 000000001e5634f1: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.728605] 00000000183f96e4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.769326] 00000000b20a94b4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.809754] 000000007bef215e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.850500] 00000000816c1095: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.891288] 00000000b28c77f6: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.932026] 00000000a3305056: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1343.972942] 00000000c446739e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.013677] 00000000f5113aae: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.054482] 000000004da60f75: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.095128] 00000000467f0c89: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.137676] 00000000c7e72d81: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.181239] 00000000d41dfd91: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.222144] 0000000090dc57ca: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.262891] 00000000a0f8a9d6: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.302856] 0000000047f123e5: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.343124] 0000000056e37cd5: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.383321] 0000000089111e42: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.423507] 00000000d71db9b3: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.462497] 00000000148c17ae: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.501416] 000000006075ced4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.540392] 000000006aa48b77: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.579454] 000000005043d7f8: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.618613] 0000000012833cdb: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.661629] 00000000055b9f9f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.701222] 0000000052ce91c9: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.740252] 00000000b350a135: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.779144] 00000000bb07a85c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.818149] 0000000081c6e075: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.857128] 00000000cba53c42: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.896097] 00000000d18e908a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.934712] 00000000f0c0c0da: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1344.975040] 00000000de3dc587: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.014881] 00000000c89cf5dd: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.054538] 0000000014407b3f: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.093740] 000000000f63ef05: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.132836] 0000000034d2338e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.176310] 0000000062639f04: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.215712] 000000004a3abf19: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.254786] 0000000061600a22: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.294000] 00000000dc954953: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.333751] 000000002d41f5ad: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.372762] 0000000030f1d334: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.412011] 0000000029fdc061: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.451606] 0000000051767b56: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.490638] 000000008f9bc2dc: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.529637] 000000001f1014dd: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.568600] 00000000a4ddbf38: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.607936] 00000000b7ff4e85: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.646965] 00000000833025ba: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.691013] 0000000009442d5a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.730149] 00000000f0c4b940: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.769263] 000000001c9e0352: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.808782] 000000005e255711: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.847775] 00000000d10d0f01: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.887154] 000000007ac060e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.926696] 00000000b4130121: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1345.965597] 0000000045f7e909: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.004777] 000000003960506e: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.044231] 000000005cd63cf7: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.083894] 0000000008fca843: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.123674] 000000004c10d2f6: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.162463] 00000000a8d87809: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.205525] 000000000425101d: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.244122] 00000000946a8e9c: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.282831] 000000000abd7e72: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.322372] 000000008b7d9850: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.361332] 00000000df8a3a2a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.400825] 0000000042bc7e5a: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.441100] 00000000b9f9dbb4: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.480853] 00000000c34370c9: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.520052] 000000000a103ceb: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 1346.559063] ================================================================== [ 1346.591444] BUG: KASAN: use-after-free in hex_dump_to_buffer+0xb23/0xb80 [ 1346.621622] Read of size 1 at addr ffff8881d21c0bd0 by task kcompactd0/263 [ 1346.652610] [ 1346.659268] CPU: 25 PID: 263 Comm: kcompactd0 Tainted: G W 5.0.0-next-20190305+ #50 [ 1346.702988] Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 [ 1346.741280] Call Trace: [ 1346.752240] dump_stack+0x62/0x9a [ 1346.767064] print_address_description.cold.2+0x9/0x28b [ 1346.790596] kasan_report.cold.3+0x7a/0xb5 [ 1346.828218] __asan_report_load1_noabort+0x19/0x20 [ 1346.849644] hex_dump_to_buffer+0xb23/0xb80 [ 1346.889066] print_hex_dump+0xf5/0x180 [ 1346.979759] kernel_poison_pages.cold.2+0x4f/0x89 [ 1347.001003] post_alloc_hook+0x186/0x290 [ 1347.018600] split_map_pages+0x1e5/0x530 [ 1347.094053] compaction_alloc+0x1050/0x25f0 [ 1347.173674] unmap_and_move+0x37/0x1e70 [ 1347.214386] migrate_pages+0x2ca/0xb20 [ 1347.295869] compact_zone.isra.2+0x19ee/0x3680 [ 1347.373747] kcompactd_do_work+0x2dd/0x670 [ 1347.445953] kcompactd+0x1d8/0x6c0 [ 1347.534669] kthread+0x32c/0x3f0 [ 1347.585440] ret_from_fork+0x35/0x40 [ 1347.601437] [ 1347.608134] The buggy address belongs to the page: [ 1347.629255] page:ffffea0007487000 count:0 mapcount:-128 mapping:0000000000000000 index:0x1 [ 1347.665980] flags: 0x5fffe000000000() [ 1347.682319] raw: 005fffe000000000 ffffea000694c008 ffffea000708fc08 0000000000000000 [ 1347.720574] raw: 0000000000000001 0000000000000003 00000000ffffff7f 0000000000000000 [ 1347.757115] page dumped because: kasan: bad access detected [ 1347.805210] [ 1347.811839] Memory state around the buggy address: [ 1347.833245] ffff8881d21c0a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 1347.865547] ffff8881d21c0b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 1347.897911] >ffff8881d21c0b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 1347.930255] ^ [ 1347.956325] ffff8881d21c0c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 1347.988841] ffff8881d21c0c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff [ 1348.021259] ================================================================== [ 1348.053236] Disabling lock debugging due to kernel taint [ 1348.077109] BUG: unable to handle kernel paging request at ffff8881d21c0bd0 [ 1348.108458] #PF error: [normal kernel read fault] [ 1348.129480] PGD 40aa01067 P4D 40aa01067 PUD 47f546067 PMD 47f4b5067 PTE 800ffffe2de3f060 [ 1348.167122] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 1348.191286] CPU: 25 PID: 263 Comm: kcompactd0 Tainted: G B W 5.0.0-next-20190305+ #50 [ 1348.234674] Hardware name: HP ProLiant DL180 Gen9/ProLiant DL180 Gen9, BIOS U20 10/25/2017 [ 1348.272578] RIP: 0010:hex_dump_to_buffer+0xe0/0xb80 [ 1348.294479] Code: 00 00 fc ff df 48 8b 5d c0 48 89 da 48 c1 ea 03 0f b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 3b 0a 00 00 48 8b 45 c0 <44> 0f b6 38 b8 01 00 00 00 48 2d a0 1a b2 b7 4c 89 fb 48 89 45 a8 [ 1348.379540] RSP: 0000:ffff8881f56df578 EFLAGS: 00010286 [ 1348.403349] RAX: ffff8881d21c0bd0 RBX: ffff8881d21c0bd0 RCX: ffffffffb67fb779 [ 1348.436156] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffb80d0fa0 [ 1348.468254] RBP: ffff8881f56df5f8 R08: fffffbfff701a1f5 R09: 0000000000000083 [ 1348.500185] R10: fffffbfff701a1f4 R11: ffffffffb80d0fa3 R12: ffff8881f56df658 [ 1348.533403] R13: 0000000000000001 R14: ffff8881d21c0bd0 R15: 0000000000000420 [ 1348.565942] FS: 0000000000000000(0000) GS:ffff8881f7c80000(0000) knlGS:0000000000000000 [ 1348.602616] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1348.628422] CR2: ffff8881d21c0bd0 CR3: 0000000408816005 CR4: 00000000001606a0 [ 1348.660521] Call Trace: [ 1348.692079] print_hex_dump+0xf5/0x180 [ 1348.787020] kernel_poison_pages.cold.2+0x4f/0x89 [ 1348.808089] post_alloc_hook+0x186/0x290 [ 1348.825648] split_map_pages+0x1e5/0x530 [ 1348.901010] compaction_alloc+0x1050/0x25f0 [ 1348.979691] unmap_and_move+0x37/0x1e70 [ 1349.016289] migrate_pages+0x2ca/0xb20 [ 1349.096343] compact_zone.isra.2+0x19ee/0x3680 [ 1349.174128] kcompactd_do_work+0x2dd/0x670 [ 1349.248832] kcompactd+0x1d8/0x6c0 [ 1349.339390] kthread+0x32c/0x3f0 [ 1349.390109] ret_from_fork+0x35/0x40 [ 1349.406571] Modules linked in: nls_iso8859_1 nls_cp437 vfat fat kvm_intel kvm irqbypass efivars ip_tables x_tables xfs sd_mod ahci libahci igb libata i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod efivarfs [ 1349.494917] CR2: ffff8881d21c0bd0 [ 1349.509747] ---[ end trace a3cd895b8ad403bc ]--- [ 1349.530429] RIP: 0010:hex_dump_to_buffer+0xe0/0xb80 [ 1349.552222] Code: 00 00 fc ff df 48 8b 5d c0 48 89 da 48 c1 ea 03 0f b6 04 02 48 89 da 83 e2 07 38 d0 7f 08 84 c0 0f 85 3b 0a 00 00 48 8b 45 c0 <44> 0f b6 38 b8 01 00 00 00 48 2d a0 1a b2 b7 4c 89 fb 48 89 45 a8 [ 1349.636407] RSP: 0000:ffff8881f56df578 EFLAGS: 00010286 [ 1349.659450] RAX: ffff8881d21c0bd0 RBX: ffff8881d21c0bd0 RCX: ffffffffb67fb779 [ 1349.691330] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffffb80d0fa0 [ 1349.723362] RBP: ffff8881f56df5f8 R08: fffffbfff701a1f5 R09: 0000000000000083 [ 1349.758554] R10: fffffbfff701a1f4 R11: ffffffffb80d0fa3 R12: ffff8881f56df658 [ 1349.792071] R13: 0000000000000001 R14: ffff8881d21c0bd0 R15: 0000000000000420 [ 1349.824033] FS: 0000000000000000(0000) GS:ffff8881f7c80000(0000) knlGS:0000000000000000 [ 1349.860332] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1349.886064] CR2: ffff8881d21c0bd0 CR3: 0000000408816005 CR4: 00000000001606a0 [ 1349.918002] Kernel panic - not syncing: Fatal exception [ 1349.941390] Kernel Offset: 0x35600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 1349.989812] ---[ end Kernel panic - not syncing: Fatal exception ]---
I don't understand this part.
@@ -2279,14 +2286,24 @@ static enum compact_result compact_zone_order(struct
zone *zone, int order,
.ignore_skip_hint = (prio == MIN_COMPACT_PRIORITY),
.ignore_block_suitable = (prio == MIN_COMPACT_PRIORITY)
};
+ struct capture_control capc = {
+ .cc = &cc,
+ .page = NULL,
+ };
+
+ if (capture)
+ current->capture_control = &capc;
That check will always be true as it is,
struct page **capture;
*capture could be NULL, but not capture because in
__alloc_pages_direct_compact(), it does,
struct page *page = NULL;
capture = &page;
On Tue, Mar 05, 2019 at 10:14:29PM -0500, Qian Cai wrote: > I don't understand this part. > > @@ -2279,14 +2286,24 @@ static enum compact_result compact_zone_order(struct > zone *zone, int order, > .ignore_skip_hint = (prio == MIN_COMPACT_PRIORITY), > .ignore_block_suitable = (prio == MIN_COMPACT_PRIORITY) > }; > + struct capture_control capc = { > + .cc = &cc, > + .page = NULL, > + }; > + > + if (capture) > + current->capture_control = &capc; > > > That check will always be true as it is, > It's a defensive check allowing for the possibility that try_to_compact_pages() is passed NULL. Originally the structure was different but I preserved the NULL check to avoid potential surprises. It could be changed but I don't think it'll help. I aim to setup a machine with your config today, try again to reproduce the problem and look at the patch again to see can I spot how it could corrupt anything.
--- a/mm/compaction.c +++ b/mm/compaction.c @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct capture_control *capc) } /* Stop if a page has been captured */ - if (capc && capc->page) { - ret = COMPACT_SUCCESS; - break; - } BUG_ON(!PageBuddy(page)); from __isolate_free_page fast_isolate_freepages at mm/compaction.c:1358 (inlined by) isolate_freepages at mm/compaction.c:1431 (inlined by) compaction_alloc at mm/compaction.c:1543