Commit 3d81acb1 authored Apr 20, 2012 by Konrad Rzeszutek Wilk

Revert "xen/p2m: m2p_find_override: use list_for_each_entry_safe"



This reverts commit b960d6c4.

If we have another thread (very likely) touched the list, we
end up hitting a problem "that the next element is wrong because
we should be able to cope with that. The problem is that the
next->next pointer would be set LIST_POISON1. " (Stefano's
comment on the patch).

Reverting for now.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

parent 186bab1c

arch/x86/xen/p2m.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -809,17 +809,21 @@ struct page *m2p_find_override(unsigned long mfn)
		{
		unsigned long flags;
		struct list_head *bucket = &m2p_overrides[mfn_hash(mfn)];
		struct page p, t, *ret;
		struct page p, ret;

		ret = NULL;

		list_for_each_entry_safe(p, t, bucket, lru) {
		spin_lock_irqsave(&m2p_override_lock, flags);

		list_for_each_entry(p, bucket, lru) {
		if (page_private(p) == mfn) {
		ret = p;
		break;
		}
		}

		spin_unlock_irqrestore(&m2p_override_lock, flags);

		return ret;
		}