diff options
| author | Wu Fengguang <fengguang.wu@intel.com> | 2009-12-16 12:19:57 +0100 |
|---|---|---|
| committer | Andi Kleen <ak@linux.intel.com> | 2009-12-16 12:19:57 +0100 |
| commit | bd1ce5f91f545730df4af492f774d9d32f5da3cb (patch) | |
| tree | 7d25f35cda1f37e30fd21bb2375f2693837d5ec5 | |
| parent | a7560fc80f33cab33176ee78f146df22b28e3338 (diff) | |
| download | blackbird-op-linux-bd1ce5f91f545730df4af492f774d9d32f5da3cb.tar.gz blackbird-op-linux-bd1ce5f91f545730df4af492f774d9d32f5da3cb.zip | |
HWPOISON: avoid grabbing the page count multiple times during madvise injection
If page is double referenced in madvise_hwpoison() and __memory_failure(),
remove_mapping() will fail because it expects page_count=2. Fix it by
not grabbing extra page count in __memory_failure().
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
| -rw-r--r-- | mm/madvise.c | 1 | ||||
| -rw-r--r-- | mm/memory-failure.c | 8 |
2 files changed, 4 insertions, 5 deletions
diff --git a/mm/madvise.c b/mm/madvise.c index 35b1479b7c9d..18970aec0d2f 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -238,7 +238,6 @@ static int madvise_hwpoison(unsigned long start, unsigned long end) page_to_pfn(p), start); /* Ignore return value for now */ __memory_failure(page_to_pfn(p), 0, 1); - put_page(p); } return ret; } diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 275f4e2df8ac..4253e14fa709 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -627,7 +627,7 @@ static void action_result(unsigned long pfn, char *msg, int result) } static int page_action(struct page_state *ps, struct page *p, - unsigned long pfn, int ref) + unsigned long pfn) { int result; int count; @@ -635,7 +635,7 @@ static int page_action(struct page_state *ps, struct page *p, result = ps->action(p, pfn); action_result(pfn, ps->msg, result); - count = page_count(p) - 1 - ref; + count = page_count(p) - 1; if (count != 0) printk(KERN_ERR "MCE %#lx: %s page still referenced by %d users\n", @@ -773,7 +773,7 @@ int __memory_failure(unsigned long pfn, int trapno, int ref) * In fact it's dangerous to directly bump up page count from 0, * that may make page_freeze_refs()/page_unfreeze_refs() mismatch. */ - if (!get_page_unless_zero(compound_head(p))) { + if (!ref && !get_page_unless_zero(compound_head(p))) { action_result(pfn, "free or high order kernel", IGNORED); return PageBuddy(compound_head(p)) ? 0 : -EBUSY; } @@ -821,7 +821,7 @@ int __memory_failure(unsigned long pfn, int trapno, int ref) res = -EBUSY; for (ps = error_states;; ps++) { if (((p->flags | lru_flag)& ps->mask) == ps->res) { - res = page_action(ps, p, pfn, ref); + res = page_action(ps, p, pfn); break; } } |
