Seen while reading the code, in handle_mm_fault(), in the case
arch_vma_access_permitted() is failing the call to mem_cgroup_oom_disable()
is not made.
To fix that, move the call to mem_cgroup_oom_enable() after calling
arch_vma_access_permitted() as it should not have entered the memcg OOM.
Fixes: bae473a423f6 ("mm: introduce fault_env")
Signed-off-by: Laurent Dufour <lduf...@linux.vnet.ibm.com>
---
mm/memory.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index 56e48e4593cb..274547075486 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3888,6 +3888,11 @@ int handle_mm_fault(struct vm_area_struct *vma, unsigned
long address,
/* do counter updates before entering really critical section. */
check_sync_rss_stat(current);
+ if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+ flags & FAULT_FLAG_INSTRUCTION,
+ flags & FAULT_FLAG_REMOTE))
+ return VM_FAULT_SIGSEGV;
+
/*
* Enable the memcg OOM handling for faults triggered in user
* space. Kernel faults are handled more gracefully.
@@ -3895,11 +3900,6 @@ int handle_mm_fault(struct vm_area_struct *vma, unsigned
long address,
if (flags & FAULT_FLAG_USER)
mem_cgroup_oom_enable();
- if (!arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
- flags & FAULT_FLAG_INSTRUCTION,
- flags & FAULT_FLAG_REMOTE))
- return VM_FAULT_SIGSEGV;
-
if (unlikely(is_vm_hugetlb_page(vma)))
ret = hugetlb_fault(vma->vm_mm, vma, address, flags);
else
--
2.7.4
