On 01. 12. 21, 9:00, Jiri Slaby wrote:
On 23. 11. 21, 22:48, Pasha Tatashin wrote:
Add page table check hooks into routines that modify user page tables.
Hi,
I bisected to this as this causes crashes during modules load:
And it's not enough to unset CONFIG_PAGE_TABLE_CHECK_ENFORCED. I had to
unset CONFIG_PAGE_TABLE_CHECK completely to get rid of this.
#PF: supervisor write access in kernel mode
#PF: error_code(0x0003) - permissions violation
PGD 6d615067 P4D 6d615067 PUD 6d616063 PMD 800000006d2001e1
Oops: 0003 [#1] PREEMPT SMP PTI
CPU: 0 PID: 6189 Comm: modprobe Kdump: loaded Tainted: G I E
5.16.0-rc2-next-20211129-vanilla #3
83846a405f0e3937f5c8dfbc7d449622b8f46369
Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be
filled by O.E.M., BIOS SDBLI944.86P 05/08/2007
RIP: 0010:jump_label_module_notify (kernel/jump_label.c:370
kernel/jump_label.c:670 kernel/jump_label.c:748)
Code: 00 48 8b 43 08 a8 02 0f 85 e9 00 00 00 48 83 e0 fc 48 c7 02 00 00
00 00 48 89 42 08 48 8b 43 08 83 e0 03 48 09 c2 48 83 ca 02 <48> 89 53
08 4d 89 66 10 49 89 6e 08 48 8b 43 08 a8 02 0f 84 98 00
All code
========
0: 00 48 8b add %cl,-0x75(%rax)
3: 43 08 a8 02 0f 85 e9 rex.XB or %bpl,-0x167af0fe(%r8)
a: 00 00 add %al,(%rax)
c: 00 48 83 add %cl,-0x7d(%rax)
f: e0 fc loopne 0xd
11: 48 c7 02 00 00 00 00 movq $0x0,(%rdx)
18: 48 89 42 08 mov %rax,0x8(%rdx)
1c: 48 8b 43 08 mov 0x8(%rbx),%rax
20: 83 e0 03 and $0x3,%eax
23: 48 09 c2 or %rax,%rdx
26: 48 83 ca 02 or $0x2,%rdx
2a:* 48 89 53 08 mov %rdx,0x8(%rbx) <--
trapping instruction
2e: 4d 89 66 10 mov %r12,0x10(%r14)
32: 49 89 6e 08 mov %rbp,0x8(%r14)
36: 48 8b 43 08 mov 0x8(%rbx),%rax
3a: a8 02 test $0x2,%al
3c: 0f .byte 0xf
3d: 84 .byte 0x84
3e: 98 cwtl
...
Code starting with the faulting instruction
===========================================
0: 48 89 53 08 mov %rdx,0x8(%rbx)
4: 4d 89 66 10 mov %r12,0x10(%r14)
8: 49 89 6e 08 mov %rbp,0x8(%r14)
c: 48 8b 43 08 mov 0x8(%rbx),%rax
10: a8 02 test $0x2,%al
12: 0f .byte 0xf
13: 84 .byte 0x84
14: 98 cwtl
...
RSP: 0018:ffffaf4dc051fbe8 EFLAGS: 00010282
RAX: 0000000000000001 RBX: ffffffff931ee760 RCX: 0000000000000001
RDX: ffff9d1aa7d43883 RSI: ffffffff91c50aa0 RDI: ffffffff931ee760
RBP: ffffffffc0782000 R08: 0000000000000020 R09: 0000000000000000
R10: ffff9d1aa7d43880 R11: 0000000000000000 R12: ffffffffc079a980
R13: ffffffffc0784080 R14: ffff9d1aa7d43ca0 R15: ffffffffc0782008
FS: 00007f87104b8740(0000) GS:ffff9d1b45c00000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff931ee768 CR3: 000000010fdce000 CR4: 00000000000006f0
Call Trace:
<TASK>
blocking_notifier_call_chain_robust (kernel/notifier.c:83
kernel/notifier.c:118 kernel/notifier.c:283 kernel/notifier.c:271)
load_module (./include/linux/notifier.h:198 kernel/module.c:3923
kernel/module.c:4100)
__do_sys_finit_module (kernel/module.c:4224)
do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)
Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
---
arch/x86/Kconfig | 1 +
arch/x86/include/asm/pgtable.h | 29 +++++++++++++++++++++++++++--
2 files changed, 28 insertions(+), 2 deletions(-)
regards,
--
js
suse labs
