On 10/01/2020 04.43, kernel test boot wrote:
Greetings, 0day kernel testing robot got the below dmesg and the first bad commit is https://github.com/0day-ci/linux/commits/Konstantin-Khlebnikov/mm-rmap-fix-reusing-mergeable-anon_vma-as-parent-when-fork/20200106-210625
Fixed in v2 [PATCH v2 1/2] mm/rmap: fix and simplify reusing mergeable anon_vma as parent when fork https://lore.kernel.org/linux-mm/157839239609.694.10268055713935919822.stgit@buzz/
commit a875b364ebe64baa45d10bd92278b1c81c2a2412 Author: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> AuthorDate: Mon Jan 6 13:42:40 2020 +0300 Commit: 0day robot <lkp@xxxxxxxxx> CommitDate: Mon Jan 6 21:06:29 2020 +0800 mm/rmap: fix reusing mergeable anon_vma as parent when forkThis fixes couple misconceptions in commit 4e4a9eb92133 ("mm/rmap.c: reusemergeable anon_vma as parent when fork").First problem caused by initialization order in dup_mmap(): vma->vm_previs set after calling anon_vma_fork(). Thus in anon_vma_fork() it points to previous VMA in parent mm. This is fixed by rearrangement in dup_mmap().If in parent VMAs: SRC1 SRC2 .. SRCn share anon-vma ANON0, then after forkbefore all patches in child process related VMAs: DST1 DST2 .. DSTn will use different anon-vmas: ANON1 ANON2 .. ANONn. Before this patch only DST1 will fork new ANON1 and following DST2 .. DSTn will share parent's ANON0. With this patch DST1 will create new ANON1 and DST2 .. DSTn will share it.Also this patch moves sharing logic out of anon_vma_clone() into morespecific anon_vma_fork() because this supposed to work only at fork(). Function anon_vma_clone() is more generic is also used at splitting VMAs.Second problem is hidden behind first one: assumption "Parent has vm_prev,which implies we have vm_prev" is wrong if first VMA in parent mm has set flag VM_DONTCOPY. Luckily prev->anon_vma doesn't dereference NULL pointer because in current code 'prev' actually is same as 'pprev'. To avoid that this patch just checks pointer and compares vm_start to verify relation between previous VMAs in parent and child.Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>Fixes: 4e4a9eb92133 ("mm/rmap.c: reuse mergeable anon_vma as parent when fork") c79f46a282 Linux 5.5-rc5 a875b364eb mm/rmap: fix reusing mergeable anon_vma as parent when fork +-----------------------------------------------------------+----------+------------+ | | v5.5-rc5 | a875b364eb | +-----------------------------------------------------------+----------+------------+ | boot_successes | 33 | 0 | | boot_failures | 3 | 13 | | BUG:kernel_timeout_in_test_stage | 1 | 1 | | Kernel_panic-not_syncing:Attempted_to_kill_init!exitcode= | 2 | | | Assertion_failed | 1 | | | WARNING:at_mm/rmap.c:#unlink_anon_vmas | 0 | 13 | | EIP:unlink_anon_vmas | 0 | 13 | +-----------------------------------------------------------+----------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot <lkp@xxxxxxxxx> [ 63.165740] Freeing unused kernel image (initmem) memory: 1292K [ 63.181481] Write protecting kernel text and read-only data: 23764k [ 63.182090] rodata_test: all tests were successful [ 63.182531] Run /init as init process [ 63.188032] ------------[ cut here ]------------ [ 63.188855] WARNING: CPU: 1 PID: 285 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.198504] Modules linked in: [ 63.199083] CPU: 1 PID: 285 Comm: init Tainted: G T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.200652] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.202103] EIP: unlink_anon_vmas+0x138/0x170 [ 63.202782] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.205655] EAX: efceeea0 EBX: ef793040 ECX: 00000001 EDX: efced258 [ 63.206697] ESI: ef793048 EDI: efceedd0 EBP: ef3cfdbc ESP: ef3cfda4 [ 63.207729] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.208834] CR0: 80050033 CR2: 77e60e70 CR3: 6f183000 CR4: 00040690 [ 63.209857] Call Trace: [ 63.210331] free_pgtables+0xa2/0x100 [ 63.210994] exit_mmap+0x98/0x160 [ 63.211600] mmput+0x6a/0x110 [ 63.212126] flush_old_exec+0x4e7/0x790 [ 63.212812] load_elf_binary+0x312/0x10ea [ 63.213534] ? find_held_lock+0x2b/0xa0 [ 63.214218] ? lock_release+0x30/0x210 [ 63.214841] ? preempt_count_sub+0x98/0x100 [ 63.215539] search_binary_handler+0x56/0x1f0 [ 63.216371] search_binary_handler+0x1b/0x30 [ 63.217083] load_script+0x1c4/0x280 [ 63.217681] search_binary_handler+0x56/0x1f0 [ 63.218557] __do_execve_file+0x655/0x7f0 [ 63.219282] sys_execve+0x26/0x30 [ 63.219865] do_int80_syscall_32+0x50/0x130 [ 63.220588] entry_INT80_32+0x112/0x117 [ 63.221270] EIP: 0x77eae864 [ 63.221790] Code: Bad RIP value. [ 63.222380] EAX: ffffffda EBX: 7fc07c24 ECX: 7fc07a5c EDX: 004cc330 [ 63.223454] ESI: 7fc07a5c EDI: 7fc07c24 EBP: 7fc079f8 ESP: 7fc07998 [ 63.224488] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.225623] ---[ end trace 99280caf5c6a62df ]--- [ 63.230470] ------------[ cut here ]------------ [ 63.230470] ------------[ cut here ]------------ [ 63.231308] WARNING: CPU: 1 PID: 285 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.232798] Modules linked in: [ 63.233323] CPU: 1 PID: 285 Comm: init Tainted: G W T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.234851] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.236286] EIP: unlink_anon_vmas+0x138/0x170 [ 63.237023] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.239208] EAX: efceec98 EBX: ef793c40 ECX: 00000001 EDX: efcede88 [ 63.239774] ESI: ef793c48 EDI: efceef70 EBP: ef3cfdbc ESP: ef3cfda4 [ 63.240337] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.240951] CR0: 80050033 CR2: 77eae85a CR3: 6f183000 CR4: 00040690 [ 63.241516] Call Trace: [ 63.241757] free_pgtables+0xa2/0x100 [ 63.242125] exit_mmap+0x98/0x160 [ 63.242435] mmput+0x6a/0x110 [ 63.242714] flush_old_exec+0x4e7/0x790 [ 63.243069] load_elf_binary+0x312/0x10ea [ 63.243436] ? find_held_lock+0x2b/0xa0 [ 63.243787] ? lock_release+0x30/0x210 [ 63.244133] ? preempt_count_sub+0x98/0x100 [ 63.244521] search_binary_handler+0x56/0x1f0 [ 63.244984] search_binary_handler+0x1b/0x30 [ 63.245374] load_script+0x1c4/0x280 [ 63.245709] search_binary_handler+0x56/0x1f0 [ 63.246189] __do_execve_file+0x655/0x7f0 [ 63.246560] sys_execve+0x26/0x30 [ 63.246870] do_int80_syscall_32+0x50/0x130 [ 63.247256] entry_INT80_32+0x112/0x117 [ 63.247611] EIP: 0x77eae864 [ 63.247878] Code: Bad RIP value. [ 63.248178] EAX: ffffffda EBX: 7fc07c24 ECX: 7fc07a5c EDX: 004cc330 [ 63.248749] ESI: 7fc07a5c EDI: 7fc07c24 EBP: 7fc079f8 ESP: 7fc07998 [ 63.249318] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.249937] ---[ end trace 99280caf5c6a62e0 ]--- [ 63.251253] ------------[ cut here ]------------ [ 63.251253] ------------[ cut here ]------------ [ 63.251982] WARNING: CPU: 1 PID: 285 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.253452] Modules linked in: [ 63.253972] CPU: 1 PID: 285 Comm: init Tainted: G W T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.255443] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.256738] EIP: unlink_anon_vmas+0x138/0x170 [ 63.257445] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.260421] EAX: efcee000 EBX: ef793280 ECX: 00000001 EDX: efcede38 [ 63.261463] ESI: ef793288 EDI: efceef08 EBP: ef3cfdbc ESP: ef3cfda4 [ 63.262419] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.263474] CR0: 80050033 CR2: 77eae85a CR3: 6f183000 CR4: 00040690 [ 63.264482] Call Trace: [ 63.264903] free_pgtables+0xa2/0x100 [ 63.265496] exit_mmap+0x98/0x160 [ 63.266044] mmput+0x6a/0x110 [ 63.266332] flush_old_exec+0x4e7/0x790 [ 63.266684] load_elf_binary+0x312/0x10ea [ 63.267052] ? find_held_lock+0x2b/0xa0 [ 63.267405] ? lock_release+0x30/0x210 [ 63.267751] ? preempt_count_sub+0x98/0x100 [ 63.268134] search_binary_handler+0x56/0x1f0 [ 63.268589] search_binary_handler+0x1b/0x30 [ 63.268980] load_script+0x1c4/0x280 [ 63.269310] search_binary_handler+0x56/0x1f0 [ 63.269770] __do_execve_file+0x655/0x7f0 [ 63.270203] sys_execve+0x26/0x30 [ 63.270511] do_int80_syscall_32+0x50/0x130 [ 63.270897] entry_INT80_32+0x112/0x117 [ 63.271249] EIP: 0x77eae864 [ 63.271512] Code: Bad RIP value. [ 63.271810] EAX: ffffffda EBX: 7fc07c24 ECX: 7fc07a5c EDX: 004cc330 [ 63.272370] ESI: 7fc07a5c EDI: 7fc07c24 EBP: 7fc079f8 ESP: 7fc07998 [ 63.272933] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.273544] ---[ end trace 99280caf5c6a62e1 ]--- [ 63.275807] ------------[ cut here ]------------ [ 63.275807] ------------[ cut here ]------------ [ 63.276245] WARNING: CPU: 1 PID: 286 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.277058] Modules linked in: [ 63.277343] CPU: 1 PID: 286 Comm: rcS Tainted: G W T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.278165] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.278914] EIP: unlink_anon_vmas+0x138/0x170 [ 63.279315] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.280965] EAX: efceee38 EBX: ef793760 ECX: 00000001 EDX: efced118 [ 63.281523] ESI: ef793768 EDI: efcee1a0 EBP: ef3cddfc ESP: ef3cdde4 [ 63.282108] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.282722] CR0: 80050033 CR2: 77d03870 CR3: 6f164000 CR4: 00040690 [ 63.283286] Call Trace: [ 63.283520] free_pgtables+0xa2/0x100 [ 63.283858] exit_mmap+0x98/0x160 [ 63.284165] mmput+0x6a/0x110 [ 63.284442] flush_old_exec+0x4e7/0x790 [ 63.284795] load_elf_binary+0x312/0x10ea [ 63.285162] ? find_held_lock+0x2b/0xa0 [ 63.285512] ? lock_release+0x30/0x210 [ 63.285857] ? preempt_count_sub+0x98/0x100 [ 63.286250] search_binary_handler+0x56/0x1f0 [ 63.286713] __do_execve_file+0x655/0x7f0 [ 63.287081] sys_execve+0x26/0x30 [ 63.287515] do_int80_syscall_32+0x50/0x130 [ 63.288230] entry_INT80_32+0x112/0x117 [ 63.288878] EIP: 0x77d31864 [ 63.289368] Code: Bad RIP value. [ 63.289911] EAX: ffffffda EBX: 0050149c ECX: 00501440 EDX: 0050144c [ 63.290960] ESI: 00501440 EDI: 0050149c EBP: 004f515f ESP: 7fdd5e88 [ 63.292002] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.293141] ---[ end trace 99280caf5c6a62e2 ]--- [ 63.298272] ------------[ cut here ]------------ [ 63.298272] ------------[ cut here ]------------ [ 63.299056] WARNING: CPU: 1 PID: 286 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.300463] Modules linked in: [ 63.300939] CPU: 1 PID: 286 Comm: rcS Tainted: G W T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.302363] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.303677] EIP: unlink_anon_vmas+0x138/0x170 [ 63.304403] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.307295] EAX: efcee7b8 EBX: ef793dc0 ECX: 00000001 EDX: efced2f8 [ 63.308245] ESI: ef793dc8 EDI: efcee0d0 EBP: ef3cddfc ESP: ef3cdde4 [ 63.309174] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.310248] CR0: 80050033 CR2: 77d3185a CR3: 6f164000 CR4: 00040690 [ 63.311318] Call Trace: [ 63.311735] free_pgtables+0xa2/0x100 [ 63.312359] exit_mmap+0x98/0x160 [ 63.312938] mmput+0x6a/0x110 [ 63.313455] flush_old_exec+0x4e7/0x790 [ 63.314136] load_elf_binary+0x312/0x10ea [ 63.314841] ? find_held_lock+0x2b/0xa0 [ 63.315500] ? lock_release+0x30/0x210 [ 63.316151] ? preempt_count_sub+0x98/0x100 [ 63.316870] search_binary_handler+0x56/0x1f0 [ 63.317726] __do_execve_file+0x655/0x7f0 [ 63.318367] sys_execve+0x26/0x30 [ 63.318890] do_int80_syscall_32+0x50/0x130 [ 63.319529] entry_INT80_32+0x112/0x117 [ 63.320152] EIP: 0x77d31864 [ 63.320606] Code: Bad RIP value. [ 63.321189] EAX: ffffffda EBX: 0050149c ECX: 00501440 EDX: 0050144c [ 63.322273] ESI: 00501440 EDI: 0050149c EBP: 004f515f ESP: 7fdd5e88 [ 63.323259] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.324357] ---[ end trace 99280caf5c6a62e3 ]--- [ 63.330230] ------------[ cut here ]------------ [ 63.330230] ------------[ cut here ]------------ [ 63.331091] WARNING: CPU: 1 PID: 286 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 [ 63.332630] Modules linked in: [ 63.333176] CPU: 1 PID: 286 Comm: rcS Tainted: G W T 5.5.0-rc5-00001-ga875b364ebe64 #1 [ 63.335413] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 63.336815] EIP: unlink_anon_vmas+0x138/0x170 [ 63.337542] Code: 00 01 00 00 c7 42 0c 22 01 00 00 e8 72 27 02 00 8d 43 08 8b 4b 08 89 da 39 f0 8d 59 f8 75 b3 83 c4 0c 5b 5e 5f 5d c3 8d 76 00 <0f> 0b eb ae 8d 74 26 00 0f 0b 83 c0 04 e8 96 cb e7 ff e9 0f ff ff [ 63.340616] EAX: efceec30 EBX: ef793340 ECX: 00000001 EDX: efcedc80 [ 63.341661] ESI: ef793348 EDI: efceec98 EBP: ef3cddfc ESP: ef3cdde4 [ 63.342620] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 EFLAGS: 00010202 [ 63.343667] CR0: 80050033 CR2: 77d3185a CR3: 6f164000 CR4: 00040690 [ 63.344640] Call Trace: [ 63.345079] free_pgtables+0xa2/0x100 [ 63.345705] exit_mmap+0x98/0x160 [ 63.346192] mmput+0x6a/0x110 [ 63.346471] flush_old_exec+0x4e7/0x790 [ 63.346826] load_elf_binary+0x312/0x10ea [ 63.347197] ? find_held_lock+0x2b/0xa0 [ 63.347547] ? lock_release+0x30/0x210 [ 63.347891] ? preempt_count_sub+0x98/0x100 [ 63.348274] search_binary_handler+0x56/0x1f0 [ 63.348734] __do_execve_file+0x655/0x7f0 [ 63.349101] sys_execve+0x26/0x30 [ 63.349406] do_int80_syscall_32+0x50/0x130 [ 63.349789] entry_INT80_32+0x112/0x117 [ 63.350159] EIP: 0x77d31864 [ 63.350426] Code: Bad RIP value. [ 63.350725] EAX: ffffffda EBX: 0050149c ECX: 00501440 EDX: 0050144c [ 63.351287] ESI: 00501440 EDI: 0050149c EBP: 004f515f ESP: 7fdd5e88 [ 63.351848] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 007b EFLAGS: 00000206 [ 63.352457] ---[ end trace 99280caf5c6a62e4 ]--- [ 63.353024] ------------[ cut here ]------------ [ 63.353024] ------------[ cut here ]------------ [ 63.353458] WARNING: CPU: 1 PID: 286 at mm/rmap.c:434 unlink_anon_vmas+0x138/0x170 # HH:MM RESULT GOOD BAD GOOD_BUT_DIRTY DIRTY_NOT_BAD git bisect start a875b364ebe64baa45d10bd92278b1c81c2a2412 c79f46a282390e0f5b306007bf7b11a46d529538 -- # first bad commit: [a875b364ebe64baa45d10bd92278b1c81c2a2412] mm/rmap: fix reusing mergeable anon_vma as parent when fork git bisect good c79f46a282390e0f5b306007bf7b11a46d529538 # 15:25 G 30 0 0 3 Linux 5.5-rc5 # extra tests with debug options git bisect good a875b364ebe64baa45d10bd92278b1c81c2a2412 # 16:23 G 10 0 10 10 mm/rmap: fix reusing mergeable anon_vma as parent when fork # extra tests on head commit of linux-review/Konstantin-Khlebnikov/mm-rmap-fix-reusing-mergeable-anon_vma-as-parent-when-fork/20200106-210625 git bisect bad a875b364ebe64baa45d10bd92278b1c81c2a2412 # 16:37 B 0 13 32 0 mm/rmap: fix reusing mergeable anon_vma as parent when fork # bad: [a875b364ebe64baa45d10bd92278b1c81c2a2412] mm/rmap: fix reusing mergeable anon_vma as parent when fork # extra tests on revert first bad commit git bisect good fc540c23cfb67790d2571027ece8a16fe804ab2e # 21:14 G 10 0 0 0 Revert "mm/rmap: fix reusing mergeable anon_vma as parent when fork" # good: [fc540c23cfb67790d2571027ece8a16fe804ab2e] Revert "mm/rmap: fix reusing mergeable anon_vma as parent when fork" --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/lkp@xxxxxxxxxxxx Intel Corporation
