On Sat, 13 Feb 2016, Kirill A. Shutemov wrote:
> Could you check if revert of fecffad25458 helps?
I reverted fecffad25458 on top of 721675fcf277cf - it oopsed with:
¢ 1851.721062! Unable to handle kernel pointer dereference in virtual kernel address space
¢ 1851.721075! failing address: 0000000000000000 TEID: 0000000000000483
¢ 1851.721078! Fault in home space mode while using kernel ASCE.
¢ 1851.721085! AS:0000000000d5c007 R3:00000000ffff0007 S:00000000ffffa800 P:000000000000003d
¢ 1851.721128! Oops: 0004 ilc:3 ¢#1! PREEMPT SMP DEBUG_PAGEALLOC
¢ 1851.721135! Modules linked in: bridge stp llc btrfs mlx4_ib mlx4_en ib_sa ib_mad vxlan xor ip6_udp_tunnel ib_core udp_tunnel ptp pps_core ib_addr ghash_s390raid6_pq prng ecb aes_s390 mlx4_core des_s390 des_generic genwqe_card sha512_s390 sha256_s390 sha1_s390 sha_common crc_itu_t dm_mod scm_block vhost_net tun vhost eadm_sch macvtap macvlan kvm autofs4
¢ 1851.721183! CPU: 7 PID: 256422 Comm: bash Not tainted 4.5.0-rc3-00058-g07923d7-dirty #178
¢ 1851.721186! task: 000000007fbfd290 ti: 000000008c604000 task.ti: 000000008c604000
¢ 1851.721189! Krnl PSW : 0704d00180000000 000000000045d3b8 (__rb_erase_color+0x280/0x308)
¢ 1851.721200! R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 0000000000000001 0000000000000020 0000000000000000 00000000bd07eff1
¢ 1851.721205! 000000000027ca10 0000000000000000 0000000083e45898 0000000077b61198
¢ 1851.721207! 000000007ce1a490 00000000bd07eff0 000000007ce1a548 000000000027ca10
¢ 1851.721210! 00000000bd07c350 00000000bd07eff0 000000008c607aa8 000000008c607a68
¢ 1851.721221! Krnl Code: 000000000045d3aa: e3c0d0080024 stg %%r12,8(%%r13)
000000000045d3b0: b9040039 lgr %%r3,%%r9
#000000000045d3b4: a53b0001 oill %%r3,1
>000000000045d3b8: e33010000024 stg %%r3,0(%%r1)
000000000045d3be: ec28000e007c cgij %%r2,0,8,45d3da
000000000045d3c4: e34020000004 lg %%r4,0(%%r2)
000000000045d3ca: b904001c lgr %%r1,%%r12
000000000045d3ce: ec143f3f0056 rosbg %%r1,%%r4,63,63,0
¢ 1851.721269! Call Trace:
¢ 1851.721273! (¢<0000000083e45898>! 0x83e45898)
¢ 1851.721279! ¢<000000000029342a>! unlink_anon_vmas+0x9a/0x1d8
¢ 1851.721282! ¢<0000000000283f34>! free_pgtables+0xcc/0x148
¢ 1851.721285! ¢<000000000028c376>! exit_mmap+0xd6/0x300
¢ 1851.721289! ¢<0000000000134db8>! mmput+0x90/0x118
¢ 1851.721294! ¢<00000000002d76bc>! flush_old_exec+0x5d4/0x700
¢ 1851.721298! ¢<00000000003369f4>! load_elf_binary+0x2f4/0x13e8
¢ 1851.721301! ¢<00000000002d6e4a>! search_binary_handler+0x9a/0x1f8
¢ 1851.721304! ¢<00000000002d8970>! do_execveat_common.isra.32+0x668/0x9a0
¢ 1851.721307! ¢<00000000002d8cec>! do_execve+0x44/0x58
¢ 1851.721310! ¢<00000000002d8f92>! SyS_execve+0x3a/0x48
¢ 1851.721315! ¢<00000000006fb096>! system_call+0xd6/0x258
¢ 1851.721317! ¢<000003ff997436d6>! 0x3ff997436d6
¢ 1851.721319! INFO: lockdep is turned off.
¢ 1851.721321! Last Breaking-Event-Address:
¢ 1851.721323! ¢<000000000045d31a>! __rb_erase_color+0x1e2/0x308
¢ 1851.721327!
¢ 1851.721329! ---¢ end trace 0d80041ac00cfae2 !---
>
> And could you share how crashes looks like? I haven't seen backtraces yet.
>
Sure. I didn't because they really looked random to me. Most of the time
in rcu or list debugging but I thought these have just been the messenger
observing a corruption first. Anyhow, here is an older one that might look
interesting:
[ 59.851421] list_del corruption. next->prev should be 000000006e1eb000, but was 0000000000000400
[ 59.851469] ------------[ cut here ]------------
[ 59.851472] WARNING: at lib/list_debug.c:71
[ 59.851475] Modules linked in: bridge stp llc btrfs xor mlx4_en vxlan ip6_udp_tunnel udp_tunnel mlx4_ib ptp pps_core ib_sa ib_mad ib_core ib_addr ghash_s390 prng raid6_pq ecb aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 mlx4_core sha_common genwqe_card scm_block crc_itu_t vhost_net tun vhost dm_mod macvtap eadm_sch macvlan kvm autofs4
[ 59.851532] CPU: 0 PID: 5400 Comm: git Not tainted 4.4.0-07794-ga4eff16-dirty #77
[ 59.851535] task: 00000000d2310000 ti: 00000000d6610000 task.ti: 00000000d6610000
[ 59.851539] Krnl PSW : 0704c00180000000 0000000000487434 (__list_del_entry+0xa4/0xe0)
[ 59.851548] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
Krnl GPRS: 0000000001a7a1cf 00000000d2310000 0000000000000054 0000000000000001
[ 59.851554] 0000000000487430 0000000000000000 0000000000000000 00000000774e6900
[ 59.851557] 000003ff53000000 000000006d4017a0 000003ff52f00000 000003ff52f00000
[ 59.851560] 000003d101780000 000000006e1eb000 0000000000487430 00000000d6613b00
[ 59.851571] Krnl Code: 0000000000487424: c02000219e3a larl %%r2,8bb098
000000000048742a: c0e5ffee05db brasl %%r14,247fe0
#0000000000487430: a7f40001 brc 15,487432
>0000000000487434: a7f40017 brc 15,487462
0000000000487438: a7390200 lghi %%r3,512
000000000048743c: ec13ffd28064 cgrj %%r1,%%r3,8,4873e0
0000000000487442: e32010000020 cg %%r2,0(%%r1)
0000000000487448: a774ffda brc 7,4873fc
[ 59.851615] Call Trace:
[ 59.851618] ([<0000000000487430>] __list_del_entry+0xa0/0xe0)
[ 59.851621] [<0000000000487498>] list_del+0x28/0x40
[ 59.851627] [<00000000001259ec>] pgtable_trans_huge_withdraw+0x74/0x90
[ 59.851632] [<00000000002bf234>] __split_huge_pmd_locked+0x3ec/0xa10
[ 59.851635] [<00000000002c4310>] __split_huge_pmd+0x118/0x218
[ 59.851639] [<00000000002810e8>] unmap_single_vma+0x2d8/0xb40
[ 59.851643] [<0000000000282d66>] zap_page_range+0x116/0x318
[ 59.851646] [<000000000029b834>] SyS_madvise+0x23c/0x5e8
[ 59.851652] [<00000000006f9f56>] system_call+0xd6/0x258
[ 59.851656] [<000003ff9bbfd282>] 0x3ff9bbfd282
[ 59.851658] 2 locks held by git/5400:
[ 59.851660] #0: (&mm->mmap_sem){++++++}, at: [<000000000029bb5a>] SyS_madvise+0x562/0x5e8
[ 59.851670] #1: (&(ptlock_ptr(page))->rlock){+.+...}, at: [<00000000002c4268>] __split_huge_pmd+0x70/0x218
[ 59.851679] Last Breaking-Event-Address:
[ 59.851682] [<0000000000487430>] __list_del_entry+0xa0/0xe0
[ 59.851686] ---[ end trace 7bce9a4f571985b6 ]---
[ 59.875754] list_del corruption. prev->next should be 000000006e1eb820, but was (null)
[ 59.875768] ------------[ cut here ]------------
[ 59.875771] WARNING: at lib/list_debug.c:68
[ 59.875774] Modules linked in: bridge stp llc btrfs xor mlx4_en vxlan ip6_udp_tunnel udp_tunnel mlx4_ib ptp pps_core ib_sa ib_mad ib_core ib_addr ghash_s390 prng raid6_pq ecb aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 mlx4_core sha_common genwqe_card scm_block crc_itu_t vhost_net tun vhost dm_mod macvtap eadm_sch macvlan kvm autofs4
[ 59.875820] CPU: 2 PID: 5402 Comm: git Tainted: G W 4.4.0-07794-ga4eff16-dirty #77
[ 59.875823] task: 00000000d2312948 ti: 00000000cfecc000 task.ti: 00000000cfecc000
[ 59.875826] Krnl PSW : 0704c00180000000 0000000000487416 (__list_del_entry+0x86/0xe0)
[ 59.875832] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
Krnl GPRS: 0000000001a7a1cf 00000000d2312948 0000000000000054 0000000000000001
[ 59.875838] 0000000000487412 0000000000000000 0000000000000000 00000000774e6900
[ 59.875841] 000003ff52000000 000000006d403b10 000003ff51f00000 000003ff51f00000
[ 59.875843] 000003d10177c000 000000006e1eb820 0000000000487412 00000000cfecfb00
[ 59.875851] Krnl Code: 0000000000487406: c02000219e2c larl %%r2,8bb05e
000000000048740c: c0e5ffee05ea brasl %%r14,247fe0
#0000000000487412: a7f40001 brc 15,487414
>0000000000487416: a7f40026 brc 15,487462
000000000048741a: b9040032 lgr %%r3,%%r2
000000000048741e: e34040080004 lg %%r4,8(%%r4)
0000000000487424: c02000219e3a larl %%r2,8bb098
000000000048742a: c0e5ffee05db brasl %%r14,247fe0
[ 59.875874] Call Trace:
[ 59.875876] ([<0000000000487412>] __list_del_entry+0x82/0xe0)
[ 59.875879] [<0000000000487498>] list_del+0x28/0x40
[ 59.875882] [<00000000001259ec>] pgtable_trans_huge_withdraw+0x74/0x90
[ 59.875885] [<00000000002bf234>] __split_huge_pmd_locked+0x3ec/0xa10
[ 59.875888] [<00000000002c4310>] __split_huge_pmd+0x118/0x218
[ 59.875891] [<00000000002810e8>] unmap_single_vma+0x2d8/0xb40
[ 59.875894] [<0000000000282d66>] zap_page_range+0x116/0x318
[ 59.875896] [<000000000029b834>] SyS_madvise+0x23c/0x5e8
[ 59.875899] [<00000000006f9f56>] system_call+0xd6/0x258
[ 59.875902] [<000003ff9bbfd282>] 0x3ff9bbfd282
[ 59.875904] 2 locks held by git/5402:
[ 59.875906] #0: (&mm->mmap_sem){++++++}, at: [<000000000029bb5a>] SyS_madvise+0x562/0x5e8
[ 59.875914] #1: (&(ptlock_ptr(page))->rlock){+.+...}, at: [<00000000002c4268>] __split_huge_pmd+0x70/0x218
[ 59.875922] Last Breaking-Event-Address:
[ 59.875925] [<0000000000487412>] __list_del_entry+0x82/0xe0
[ 59.875927] ---[ end trace 7bce9a4f571985b7 ]---
[ 59.875935] ------------[ cut here ]------------
[ 59.875937] kernel BUG at mm/huge_memory.c:2884!
[ 59.875979] illegal operation: 0001 ilc:1 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 59.875986] Modules linked in: bridge stp llc btrfs xor mlx4_en vxlan ip6_udp_tunnel udp_tunnel mlx4_ib ptp pps_core ib_sa ib_mad ib_core ib_addr ghash_s390 prng raid6_pq ecb aes_s390 des_s390 des_generic sha512_s390 sha256_s390 sha1_s390 mlx4_core sha_common genwqe_card scm_block crc_itu_t vhost_net tun vhost dm_mod macvtap eadm_sch macvlan kvm autofs4
[ 59.876033] CPU: 2 PID: 5402 Comm: git Tainted: G W 4.4.0-07794-ga4eff16-dirty #77
[ 59.876036] task: 00000000d2312948 ti: 00000000cfecc000 task.ti: 00000000cfecc000
[ 59.876039] Krnl PSW : 0704d00180000000 00000000002bf3aa (__split_huge_pmd_locked+0x562/0xa10)
[ 59.876045] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 0000000001a7a1cf 000003d10177c000 0000000000044068 000000005df00215
[ 59.876051] 0000000000000001 0000000000000001 0000000000000000 00000000774e6900
[ 59.876054] 000003ff52000000 000000006d403b10 000000006e1eb800 000003ff51f00000
[ 59.876058] 000003d10177c000 0000000000715190 00000000002bf234 00000000cfecfb58
[ 59.876068] Krnl Code: 00000000002bf39c: d507d010a000 clc 16(8,%%r13),0(%%r10)
00000000002bf3a2: a7840004 brc 8,2bf3aa
#00000000002bf3a6: a7f40001 brc 15,2bf3a8
>00000000002bf3aa: 91407440 tm 1088(%%r7),64
00000000002bf3ae: a7840208 brc 8,2bf7be
00000000002bf3b2: a7f401e9 brc 15,2bf784
00000000002bf3b6: 9104a006 tm 6(%%r10),4
00000000002bf3ba: a7740004 brc 7,2bf3c2
[ 59.876089] Call Trace:
[ 59.876092] ([<00000000002bf234>] __split_huge_pmd_locked+0x3ec/0xa10)
[ 59.876095] [<00000000002c4310>] __split_huge_pmd+0x118/0x218
[ 59.876099] [<00000000002810e8>] unmap_single_vma+0x2d8/0xb40
[ 59.876102] [<0000000000282d66>] zap_page_range+0x116/0x318
[ 59.876105] [<000000000029b834>] SyS_madvise+0x23c/0x5e8
[ 59.876108] [<00000000006f9f56>] system_call+0xd6/0x258
[ 59.876111] [<000003ff9bbfd282>] 0x3ff9bbfd282
[ 59.876113] INFO: lockdep is turned off.
[ 59.876115] Last Breaking-Event-Address:
[ 59.876118] [<00000000002bf3a6>] __split_huge_pmd_locked+0x55e/0xa10
[ 59.876122]
[ 59.876124] ---[ end trace 7bce9a4f571985b8 ]---
[ 59.876128] BUG: sleeping function called from invalid context at include/linux/sched.h:2791
[ 59.876130] in_atomic(): 1, irqs_disabled(): 0, pid: 5402, name: git
[ 59.876132] INFO: lockdep is turned off.
[ 59.876134] Preemption disabled at:[<00000000002c4268>] __split_huge_pmd+0x70/0x218
[ 59.876138]
[ 59.876141] CPU: 2 PID: 5402 Comm: git Tainted: G D W 4.4.0-07794-ga4eff16-dirty #77
[ 59.876144] 00000000cfecf610 00000000cfecf6a0 0000000000000002 0000000000000000
00000000cfecf740 00000000cfecf6b8 00000000cfecf6b8 0000000000113402
0000000000000000 000000000089ab4e 00000000008b0a84 0704d0010000000b
00000000cfecf700 00000000cfecf6a0 0000000000000000 0000000000000000
0000000000000000 0000000000113402 00000000cfecf6a0 00000000cfecf700
[ 59.876176] Call Trace:
[ 59.876182] ([<000000000011330e>] show_trace+0x126/0x148)
[ 59.876185] [<00000000001133b8>] show_stack+0x88/0xe8
[ 59.876189] [<000000000045549a>] dump_stack+0x7a/0xd8
[ 59.876193] [<00000000001666c6>] ___might_sleep+0x236/0x248
[ 59.876198] [<000000000014a314>] exit_signals+0x3c/0x158
[ 59.876202] [<000000000013a4e0>] do_exit+0x140/0xd18
[ 59.876206] [<00000000001137c4>] die+0x164/0x170
[ 59.876209] [<0000000000100ac6>] do_report_trap+0x14e/0x160
[ 59.876211] [<0000000000100c94>] illegal_op+0x134/0x148
[ 59.876214] [<00000000006fa26c>] pgm_check_handler+0x15c/0x1b4
[ 59.876217] [<00000000002bf3aa>] __split_huge_pmd_locked+0x562/0xa10
[ 59.876221] ([<00000000002bf234>] __split_huge_pmd_locked+0x3ec/0xa10)
[ 59.876223] [<00000000002c4310>] __split_huge_pmd+0x118/0x218
[ 59.876226] [<00000000002810e8>] unmap_single_vma+0x2d8/0xb40
[ 59.876229] [<0000000000282d66>] zap_page_range+0x116/0x318
[ 59.876232] [<000000000029b834>] SyS_madvise+0x23c/0x5e8
[ 59.876235] [<00000000006f9f56>] system_call+0xd6/0x258
[ 59.876238] [<000003ff9bbfd282>] 0x3ff9bbfd282
[ 59.876240] INFO: lockdep is turned off.
[ 59.876243] note: git[5402] exited with preempt_count 1