linux

iv/linux

History

Nikunj A Dadhania fffb532378 KVM: x86: Check for rmaps allocation

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: Peter Xu <peterx@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220105040337.4234-1-nikunj@amd.com>
Cc: stable@vger.kernel.org
Fixes: 3bcd0662d66f ("KVM: X86: Introduce mmu_rmaps_stat per-vm debugfs file")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2022-01-07 12:04:01 -05:00

alpha

futex: Wireup futex_waitv syscall

2021-11-25 14:26:12 +01:00

arc

Add linux/cacheflush.h

2021-11-17 10:36:15 -05:00

arm

ARM: SoC fixes for v5.16, part 2

2021-11-25 10:31:37 -08:00

arm64

arm64 fixes for -rc4