The patch titled
Subject: mm/memory-failure.c: don't access uninitialized memmaps in memory_failure()
has been added to the -mm tree. Its filename is
mm-memory-failurec-dont-access-uninitialized-memmaps-in-memory_failure.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory-failurec-dont-access-uninitialized-memmaps-in-memory_failure.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory-failurec-dont-access-uninitialized-memmaps-in-memory_failure.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: mm/memory-failure.c: don't access uninitialized memmaps in memory_failure()
We should check for pfn_to_online_page() to not access uninitialized
memmaps. Reshuffle the code so we don't have to duplicate the error
message.
Link: http://lkml.kernel.org/r/20191009142435.3975-3-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memory-failure.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failurec-dont-access-uninitialized-memmaps-in-memory_failure
+++ a/mm/memory-failure.c
@@ -1253,17 +1253,19 @@ int memory_failure(unsigned long pfn, in
if (!sysctl_memory_failure_recovery)
panic("Memory failure on page %lx", pfn);
- if (!pfn_valid(pfn)) {
+ p = pfn_to_online_page(pfn);
+ if (!p) {
+ if (pfn_valid(pfn)) {
+ pgmap = get_dev_pagemap(pfn, NULL);
+ if (pgmap)
+ return memory_failure_dev_pagemap(pfn, flags,
+ pgmap);
+ }
pr_err("Memory failure: %#lx: memory outside kernel control\n",
pfn);
return -ENXIO;
}
- pgmap = get_dev_pagemap(pfn, NULL);
- if (pgmap)
- return memory_failure_dev_pagemap(pfn, flags, pgmap);
-
- p = pfn_to_page(pfn);
if (PageHuge(p))
return memory_failure_hugetlb(pfn, flags);
if (TestSetPageHWPoison(p)) {
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-dont-access-uninitialized-memmaps-in-fs-proc-pagec.patch
mm-memory-failurec-dont-access-uninitialized-memmaps-in-memory_failure.patch
mm-memory_hotplug-export-generic_online_page.patch
hv_balloon-use-generic_online_page.patch
mm-memory_hotplug-remove-__online_page_free-and-__online_page_increment_counters.patch
mm-memory_hotplug-dont-access-uninitialized-memmaps-in-shrink_pgdat_span.patch
mm-memory_hotplug-dont-access-uninitialized-memmaps-in-shrink_zone_span.patch
mm-memory_hotplug-shrink-zones-when-offlining-memory.patch
mm-memory_hotplug-poison-memmap-in-remove_pfn_range_from_zone.patch
mm-memory_hotplug-we-always-have-a-zone-in-find_smallestbiggest_section_pfn.patch
mm-memory_hotplug-dont-check-for-all-holes-in-shrink_zone_span.patch
mm-memory_hotplug-drop-local-variables-in-shrink_zone_span.patch
mm-memory_hotplug-cleanup-__remove_pages.patch
