Commit 9113eaf3 authored by zhenwei pi's avatar zhenwei pi Committed by Andrew Morton
Browse files

mm/memory-failure.c: add hwpoison_filter for soft offline 

hwpoison_filter is missing in the soft offline path, this leads an issue:
after enabling the corrupt filter, the user process still has a chance to
inject hwpoison fault by madvise(addr, len, MADV_SOFT_OFFLINE) at PFN
which is expected to reject.

Also do a minor change in comment of memory_failure().

Link: https://lkml.kernel.org/r/20220509105641.491313-4-pizhenwei@bytedance.com


Signed-off-by: default avatarzhenwei pi <pizhenwei@bytedance.com>
Acked-by: default avatarNaoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent c8bd84f7

mm/memory-failure.c

+14 −2
Original line number Diff line number Diff line
@@ -1751,7 +1751,7 @@ static DEFINE_MUTEX(mf_mutex); 
 * enabled and no spinlocks hold.

 *

 * Return: 0 for successfully handled the memory error,

 *         -EOPNOTSUPP for memory_filter() filtered the error event,

 *         -EOPNOTSUPP for hwpoison_filter() filtered the error event,

 *         < 0(except -EOPNOTSUPP) on failure.

 */

int memory_failure(unsigned long pfn, int flags)
@@ -2308,7 +2308,9 @@ static void put_ref_page(struct page *page) 
 * @pfn: pfn to soft-offline

 * @flags: flags. Same as memory_failure().

 *

 * Returns 0 on success, otherwise negated errno.

 * Returns 0 on success

 *         -EOPNOTSUPP for hwpoison_filter() filtered the error event

 *         < 0 otherwise negated errno.

 *

 * Soft offline a page, by migration or invalidation,

 * without killing anything. This is for the case when
@@ -2359,6 +2361,16 @@ int soft_offline_page(unsigned long pfn, int flags) 
	ret = get_hwpoison_page(page, flags | MF_SOFT_OFFLINE);

	put_online_mems();



	if (hwpoison_filter(page)) {

		if (ret > 0)

			put_page(page);

		else

			put_ref_page(ref_page);



		mutex_unlock(&mf_mutex);

		return -EOPNOTSUPP;

	}



	if (ret > 0) {

		ret = soft_offline_in_use_page(page);

	} else if (ret == 0) {