[PATCH] [7/16] HWPOISON: Add various poison checks in mm/memory.c

Andi Kleen
2009-05-27T20:14:55Z

Bail out early when hardware poisoned pages are found in page fault handling.
Since they are poisoned they should not be mapped freshly into processes,
because that would cause another (potentially deadly) machine check

This is generally handled in the same way as OOM, just a different
error code is returned to the architecture code.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

---
mm/memory.c | 3 +++
1 file changed, 3 insertions(+)

Index: linux/mm/memory.c
===================================================================
--- linux.orig/mm/memory.c 2009-05-27 21:14:21.000000000 +0200
+++ linux/mm/memory.c 2009-05-27 21:14:21.000000000 +0200
@@ -2659,6 +2659,9 @@
if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
return ret;

+ if (unlikely(PageHWPoison(vmf.page)))
+ return VM_FAULT_HWPOISON;
+
/*
* For consistency in subsequent calls, make the faulted page always
* locked.