The patch titled Subject: mm: fix invalid use of pfn_valid_within in test_pages_in_a_zone has been added to the -mm tree. Its filename is mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone.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/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: James Custer <jcuster@xxxxxxx> Subject: mm: fix invalid use of pfn_valid_within in test_pages_in_a_zone Offlining memory by 'echo 0 > /sys/devices/system/memory/memory#/online' or reading valid_zones 'cat /sys/devices/system/memory/memory#/valid_zones' causes BUG: unable to handle kernel paging request due to invalid use of pfn_valid_within. This is due to a bug in test_pages_in_a_zone. In order to use pfn_valid_within within a MAX_ORDER_NR_PAGES block of pages, a valid pfn within the block must first be found. There only needs to be one valid pfn found in test_pages_in_a_zone in the first place. So the fix is to replace pfn_valid_within with pfn_valid such that the first valid pfn within the pageblock is found (if it exists). This works independently of CONFIG_HOLES_IN_ZONE. Signed-off-by: James Custer <jcuster@xxxxxxx> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Cc: Russ Anderson <rja@xxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff -puN mm/memory_hotplug.c~mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone mm/memory_hotplug.c --- a/mm/memory_hotplug.c~mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone +++ a/mm/memory_hotplug.c @@ -1331,7 +1331,7 @@ int is_mem_section_removable(unsigned lo } /* - * Confirm all pages in a range [start, end) is belongs to the same zone. + * Confirm all pages in a range [start, end) belong to the same zone. */ int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) { @@ -1342,10 +1342,11 @@ int test_pages_in_a_zone(unsigned long s for (pfn = start_pfn; pfn < end_pfn; pfn += MAX_ORDER_NR_PAGES) { - i = 0; - /* This is just a CONFIG_HOLES_IN_ZONE check.*/ - while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) - i++; + /* Find the first valid pfn in this pageblock */ + for (i = 0; i < MAX_ORDER_NR_PAGES; i++) { + if (pfn_valid(pfn + i)) + break; + } if (i == MAX_ORDER_NR_PAGES) continue; page = pfn_to_page(pfn + i); _ Patches currently in -mm which might be from jcuster@xxxxxxx are mm-fix-invalid-use-of-pfn_valid_within-in-test_pages_in_a_zone.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html