Re: NULL pointer dereference during memory hotremove
From: Pavel Tatashin
Date: Fri May 17 2019 - 13:35:47 EST
On Fri, May 17, 2019 at 1:24 PM Pavel Tatashin
<pasha.tatashin@xxxxxxxxxx> wrote:
>
> On Fri, May 17, 2019 at 1:22 PM Pavel Tatashin
> <pasha.tatashin@xxxxxxxxxx> wrote:
> >
> > On Fri, May 17, 2019 at 10:38 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote:
> > >
> > > On Fri 17-05-19 10:20:38, Pavel Tatashin wrote:
> > > > This panic is unrelated to circular lock issue that I reported in a
> > > > separate thread, that also happens during memory hotremove.
> > > >
> > > > xakep ~/x/linux$ git describe
> > > > v5.1-12317-ga6a4b66bd8f4
> > >
> > > Does this happen on 5.0 as well?
> >
> > Yes, just reproduced it on 5.0 as well. Unfortunately, I do not have a
> > script, and have to do it manually, also it does not happen every
> > time, it happened on 3rd time for me.
>
> Actually, sorry, I have not tested 5.0, I compiled 5.0, but my script
> still tested v5.1-12317-ga6a4b66bd8f4 build. I will report later if I
> am able to reproduce it on 5.0.
OK, confirmed on 5.0 as well, took 4 tries to reproduce:
(qemu) [ 17.104486] Offlined Pages 32768
[ 17.105543] Built 1 zonelists, mobility grouping on. Total pages: 1515892
[ 17.106475] Policy zone: Normal
[ 17.107029] BUG: unable to handle kernel NULL pointer dereference
at 0000000000000698
[ 17.107645] #PF error: [normal kernel read fault]
[ 17.108038] PGD 0 P4D 0
[ 17.108287] Oops: 0000 [#1] SMP PTI
[ 17.108557] CPU: 5 PID: 313 Comm: kworker/u16:5 Not tainted 5.0.0_pt_pmem1 #2
[ 17.109128] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.12.0-20181126_142135-anatol 04/01/2014
[ 17.109910] Workqueue: kacpi_hotplug acpi_hotplug_work_fn
[ 17.110323] RIP: 0010:__remove_pages+0x2f/0x520
[ 17.110674] Code: 41 56 41 55 49 89 fd 41 54 55 53 48 89 d3 48 83
ec 68 48 89 4c 24 08 65 48 8b 04 25 28 00 00 00 48 89 44 24 60 31 c0
48 89 f8 <48> 2b 47 58 48 3d 00 19 00 00 0f 85 7f 03 00 00 48 85 c9 0f
84 df
[ 17.112114] RSP: 0018:ffffb43b815f3ca8 EFLAGS: 00010246
[ 17.112518] RAX: 0000000000000640 RBX: 0000000000040000 RCX: 0000000000000000
[ 17.113073] RDX: 0000000000040000 RSI: 0000000000240000 RDI: 0000000000000640
[ 17.113615] RBP: 0000000240000000 R08: 0000000000000000 R09: 0000000040000000
[ 17.114186] R10: 0000000040000000 R11: 0000000240000000 R12: ffffe382c9000000
[ 17.114743] R13: 0000000000000640 R14: 0000000000040000 R15: 0000000000240000
[ 17.115288] FS: 0000000000000000(0000) GS:ffff979539b40000(0000)
knlGS:0000000000000000
[ 17.115911] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 17.116356] CR2: 0000000000000698 CR3: 0000000133c22004 CR4: 0000000000360ee0
[ 17.116913] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 17.117467] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 17.118016] Call Trace:
[ 17.118214] ? memblock_isolate_range+0xc4/0x139
[ 17.118570] ? firmware_map_remove+0x48/0x90
[ 17.118908] arch_remove_memory+0x7b/0xc0
[ 17.119216] __remove_memory+0x93/0xc0
[ 17.119528] acpi_memory_device_remove+0x67/0xe0
[ 17.119890] acpi_bus_trim+0x50/0x90
[ 17.120167] acpi_device_hotplug+0x2fc/0x460
[ 17.120498] acpi_hotplug_work_fn+0x15/0x20
[ 17.120834] process_one_work+0x2a0/0x650
[ 17.121146] worker_thread+0x34/0x3d0
[ 17.121432] ? process_one_work+0x650/0x650
[ 17.121772] kthread+0x118/0x130
[ 17.122032] ? kthread_create_on_node+0x60/0x60
[ 17.122413] ret_from_fork+0x3a/0x50
[ 17.122727] Modules linked in:
[ 17.122983] CR2: 0000000000000698
[ 17.123250] ---[ end trace 389c4034f6d42e6f ]---
[ 17.123618] RIP: 0010:__remove_pages+0x2f/0x520
[ 17.123979] Code: 41 56 41 55 49 89 fd 41 54 55 53 48 89 d3 48 83
ec 68 48 89 4c 24 08 65 48 8b 04 25 28 00 00 00 48 89 44 24 60 31 c0
48 89 f8 <48> 2b 47 58 48 3d 00 19 00 00 0f 85 7f 03 00 00 48 85 c9 0f
84 df
[ 17.125410] RSP: 0018:ffffb43b815f3ca8 EFLAGS: 00010246
[ 17.125818] RAX: 0000000000000640 RBX: 0000000000040000 RCX: 0000000000000000
[ 17.126359] RDX: 0000000000040000 RSI: 0000000000240000 RDI: 0000000000000640
[ 17.126906] RBP: 0000000240000000 R08: 0000000000000000 R09: 0000000040000000
[ 17.127453] R10: 0000000040000000 R11: 0000000240000000 R12: ffffe382c9000000
[ 17.128008] R13: 0000000000000640 R14: 0000000000040000 R15: 0000000000240000
[ 17.128555] FS: 0000000000000000(0000) GS:ffff979539b40000(0000)
knlGS:0000000000000000
[ 17.129182] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 17.129627] CR2: 0000000000000698 CR3: 0000000133c22004 CR4: 0000000000360ee0
[ 17.130182] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 17.130744] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 17.131293] BUG: sleeping function called from invalid context at
include/linux/percpu-rwsem.h:34
[ 17.132050] in_atomic(): 0, irqs_disabled(): 1, pid: 313, name: kworker/u16:5
[ 17.132596] INFO: lockdep is turned off.
[ 17.132908] irq event stamp: 14046
[ 17.133175] hardirqs last enabled at (14045): [<ffffffffadbf3b1a>]
kfree+0xba/0x230
[ 17.133777] hardirqs last disabled at (14046): [<ffffffffada01b03>]
trace_hardirqs_off_thunk+0x1a/0x1c
[ 17.134497] softirqs last enabled at (13446): [<ffffffffae2c804c>]
peernet2id+0x4c/0x70
[ 17.135119] softirqs last disabled at (13444): [<ffffffffae2c802d>]
peernet2id+0x2d/0x70
[ 17.135739] CPU: 5 PID: 313 Comm: kworker/u16:5 Tainted: G D
5.0.0_pt_pmem1 #2
[ 17.136389] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.12.0-20181126_142135-anatol 04/01/2014
[ 17.137169] Workqueue: kacpi_hotplug acpi_hotplug_work_fn
[ 17.137589] Call Trace:
[ 17.137792] dump_stack+0x67/0x90
[ 17.138160] ___might_sleep.cold.87+0x9f/0xaf
[ 17.138497] exit_signals+0x2b/0x240
[ 17.138794] do_exit+0xab/0xc10
[ 17.139055] ? process_one_work+0x650/0x650
[ 17.139406] ? kthread+0x118/0x130
[ 17.139686] rewind_stack_do_exit+0x17/0x20
# uname -a
Linux pt 5.0.0 #2 SMP Fri May 17 13:28:36 EDT 2019 x86_64 GNU/Linux