BUG: Sporadic crashes with current Linus tree

From: Thomas Gleixner
Date: Thu Sep 14 2017 - 03:38:14 EST


Hi!

I've seen the following crash sporadically with commit 46c1e79fee:

Have not seen that with 3882a734c19b, though I saw the PCID warnings on
that machine.

I have no idea how to reproduce so bisecting is pretty much pointless. Any
idea what to do?

Thanks,

tglx


BUG: unable to handle kernel paging request at ffffffffffffffd8
IP: __memmove+0x24/0x1a0
PGD 1e17c0c067 P4D 1e17c0c067 PUD 1e17c0e067 PMD 0
Oops: 0002 [#1] SMP
CPU: 43 PID: 1958 Comm: rsyslogd Tainted: G W 4.13.0+ #184
task: ffff9eb5e8780080 task.stack: ffffb648a08cc000
RIP: 0010:__memmove+0x24/0x1a0
RSP: 0018:ffffb648a08cfef0 EFLAGS: 00252097
RAX: ffffffffffffffd8 RBX: ffffffffffffff50 RCX: 0000000000000028
RDX: 0000000000000028 RSI: ffffb648a08cffd8 RDI: ffffffffffffffd8
RBP: ffffb648a08cff10 R08: ffffb648a08d0000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: ffffb648a08cff20 R14: 00007fffef2ed9a8 R15: 0000000000000000
FS: 00007f05281eff80(0000) GS:ffff9eb5ff5c0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd8 CR3: 000000302857c002 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
? fixup_bad_iret+0x3c/0x60
error_entry+0xb4/0xc0
? general_protection+0xc/0x30
Code: 90 90 90 90 90 90 90 48 89 f8 48 83 fa 20 0f 82 03 01 00 00 48 39 fe 7d 0f 49 89 f0 49 01 d0 49 39 f8 0f 8f 9f 00 00 00 48 89 d1 <f3> a4 c3 48 81 fa a8 02 00 00 72 05 40 38 fe 74 3b 48 83 ea 20
RIP: __memmove+0x24/0x1a0 RSP: ffffb648a08cfef0
CR2: ffffffffffffffd8
[ end trace 72d77f3e20344f94 ]---