HWPOISON: abort on failed unmap

commit 1668bfd5be upstream.

Don't try to isolate a still mapped page. Otherwise we will hit the
BUG_ON(page_mapped(page)) in __remove_from_page_cache().

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Wu Fengguang
2009-12-16 12:19:58 +01:00
committed by Greg Kroah-Hartman
parent b30604b9fd
commit d0cddca762

View File

@@ -637,7 +637,7 @@ static int page_action(struct page_state *ps, struct page *p,
* Do all that is necessary to remove user space mappings. Unmap
* the pages and send SIGBUS to the processes if the data was dirty.
*/
static void hwpoison_user_mappings(struct page *p, unsigned long pfn,
static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
int trapno)
{
enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS;
@@ -647,15 +647,18 @@ static void hwpoison_user_mappings(struct page *p, unsigned long pfn,
int i;
int kill = 1;
if (PageReserved(p) || PageCompound(p) || PageSlab(p) || PageKsm(p))
return;
if (PageReserved(p) || PageSlab(p))
return SWAP_SUCCESS;
/*
* This check implies we don't kill processes if their pages
* are in the swap cache early. Those are always late kills.
*/
if (!page_mapped(p))
return;
return SWAP_SUCCESS;
if (PageCompound(p) || PageKsm(p))
return SWAP_FAIL;
if (PageSwapCache(p)) {
printk(KERN_ERR
@@ -717,6 +720,8 @@ static void hwpoison_user_mappings(struct page *p, unsigned long pfn,
*/
kill_procs_ao(&tokill, !!PageDirty(p), trapno,
ret != SWAP_SUCCESS, pfn);
return ret;
}
int __memory_failure(unsigned long pfn, int trapno, int ref)
@@ -786,8 +791,13 @@ int __memory_failure(unsigned long pfn, int trapno, int ref)
/*
* Now take care of user space mappings.
* Abort on fail: __remove_from_page_cache() assumes unmapped page.
*/
hwpoison_user_mappings(p, pfn, trapno);
if (hwpoison_user_mappings(p, pfn, trapno) != SWAP_SUCCESS) {
printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
res = -EBUSY;
goto out;
}
/*
* Torn down by someone else?