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authorLiu Shixin <liushixin2@huawei.com>2021-12-25 08:12:58 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-12-29 14:26:05 +0300
commit1f207076740101fed87074a6bc924dbe806f08a5 (patch)
tree7cfad26b7e4e4835ed8cd4180f22cb58d7b8e6a2 /mm/memory-failure.c
parentac61b9c6c0549aaeb98194cf429d93c41bfe5f79 (diff)
downloadlinux-1f207076740101fed87074a6bc924dbe806f08a5.tar.xz
mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()
commit 2a57d83c78f889bf3f54eede908d0643c40d5418 upstream. Hulk Robot reported a panic in put_page_testzero() when testing madvise() with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying get_any_page(). This is because we keep MF_COUNT_INCREASED flag in second try but the refcnt is not increased. page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:737! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 5 PID: 2135 Comm: sshd Tainted: G B 5.16.0-rc6-dirty #373 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: release_pages+0x53f/0x840 Call Trace: free_pages_and_swap_cache+0x64/0x80 tlb_flush_mmu+0x6f/0x220 unmap_page_range+0xe6c/0x12c0 unmap_single_vma+0x90/0x170 unmap_vmas+0xc4/0x180 exit_mmap+0xde/0x3a0 mmput+0xa3/0x250 do_exit+0x564/0x1470 do_group_exit+0x3b/0x100 __do_sys_exit_group+0x13/0x20 __x64_sys_exit_group+0x16/0x20 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Modules linked in: ---[ end trace e99579b570fe0649 ]--- RIP: 0010:release_pages+0x53f/0x840 Link: https://lkml.kernel.org/r/20211221074908.3910286-1-liushixin2@huawei.com Fixes: b94e02822deb ("mm,hwpoison: try to narrow window race for free pages") Signed-off-by: Liu Shixin <liushixin2@huawei.com> Reported-by: Hulk Robot <hulkci@huawei.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/memory-failure.c')
-rw-r--r--mm/memory-failure.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 01445ddff58d..aef267c6a724 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1938,6 +1938,7 @@ retry:
else if (ret == 0)
if (soft_offline_free_page(page) && try_again) {
try_again = false;
+ flags &= ~MF_COUNT_INCREASED;
goto retry;
}