Commit a3b947ea authored Sep 16, 2009 by Andi Kleen Committed by Andi Kleen Sep 16, 2009

HWPOISON: Add poison check to page fault handling



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.

v2: Do a page unlock if needed (Fengguang Wu)

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

parent d1737fdb

mm/memory.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -2711,6 +2711,12 @@ static int __do_fault(struct mm_struct mm, struct vm_area_struct vma,
		if (unlikely(ret & (VM_FAULT_ERROR \| VM_FAULT_NOPAGE)))
		return ret;

		if (unlikely(PageHWPoison(vmf.page))) {
		if (ret & VM_FAULT_LOCKED)
		unlock_page(vmf.page);
		return VM_FAULT_HWPOISON;
		}

		/*
		* For consistency in subsequent calls, make the faulted page always
		* locked.

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