lkml.org 
[lkml]   [2022]   [Jan]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH v2] KVM: x86: Check for rmaps allocation
From
On 1/7/22 18:01, Sean Christopherson wrote:
> On Wed, Jan 05, 2022, Peter Xu wrote:
>> On Wed, Jan 05, 2022 at 09:33:37AM +0530, Nikunj A Dadhania wrote:
>>> With TDP MMU being the default now, access to mmu_rmaps_stat debugfs
>>> file causes following oops:
>>>
>>> BUG: kernel NULL pointer dereference, address: 0000000000000000
>>> PGD 0 P4D 0
>>> Oops: 0000 [#1] PREEMPT SMP NOPTI
>>> CPU: 7 PID: 3185 Comm: cat Not tainted 5.16.0-rc4+ #204
>>> RIP: 0010:pte_list_count+0x6/0x40
>>> Call Trace:
>>> <TASK>
>>> ? kvm_mmu_rmaps_stat_show+0x15e/0x320
>>> seq_read_iter+0x126/0x4b0
>>> ? aa_file_perm+0x124/0x490
>>> seq_read+0xf5/0x140
>>> full_proxy_read+0x5c/0x80
>>> vfs_read+0x9f/0x1a0
>>> ksys_read+0x67/0xe0
>>> __x64_sys_read+0x19/0x20
>>> do_syscall_64+0x3b/0xc0
>>> entry_SYSCALL_64_after_hwframe+0x44/0xae
>>> RIP: 0033:0x7fca6fc13912
>>>
>>> Return early when rmaps are not present.
>>>
>>> Reported-by: Vasant Hegde <vasant.hegde@amd.com>
>>> Tested-by: Vasant Hegde <vasant.hegde@amd.com>
>>> Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
>>> ---
>
> Reviewed-by: Sean Christopherson <seanjc@google.com>
>

Queued, thanks.

paolo

\
 
 \ /
  Last update: 2022-01-07 18:04    [W:0.362 / U:0.908 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site