Re: [PATCH 1/2] mm/hwpoison: fix fail to split THP w/ refcount held

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Naoya,

On 8/10/15 4:10 PM, Naoya Horiguchi wrote:
On Mon, Aug 10, 2015 at 02:32:30PM +0800, Wanpeng Li wrote:
THP pages will get a refcount in madvise_hwpoison() w/ MF_COUNT_INCREASED
flag, however, the refcount is still held when fail to split THP pages.

Fix it by reducing the refcount of THP pages when fail to split THP.

Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
It seems that the same conditional put_page() would be added to
"soft offline: %#lx page already poisoned" branch too, right?

PageHWPoison() is just called before the soft_offline_page() in madvise_hwpoion(). I think the PageHWPosion() check in soft_offline_page() makes more sense for the other soft_offline_page() callsites which don't have the
refcount held.

Regards,
Wanpeng Li


---
  mm/memory-failure.c |    2 ++
  1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 8077b1c..56b8a71 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1710,6 +1710,8 @@ int soft_offline_page(struct page *page, int flags)
  		if (PageAnon(hpage) && unlikely(split_huge_page(hpage))) {
  			pr_info("soft offline: %#lx: failed to split THP\n",
  				pfn);
+			if (flags & MF_COUNT_INCREASED)
+				put_page(page);
  			return -EBUSY;
  		}
  	}
--
1.7.1

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>



[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]