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| author | KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> | 2014-02-06 21:04:24 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-02-06 22:48:51 +0100 |
| commit | a85d9df1ea1d23682a0ed1e100e6965006595d06 (patch) | |
| tree | d8c1bee9c60b1f40efb20f3fcaed54d762026fd8 | |
| parent | mm/swap: fix race on swap_info reuse between swapoff and swapon (diff) | |
| download | linux-a85d9df1ea1d23682a0ed1e100e6965006595d06.tar.xz linux-a85d9df1ea1d23682a0ed1e100e6965006595d06.zip | |
mm: __set_page_dirty_nobuffers() uses spin_lock_irqsave() instead of spin_lock_irq()
During aio stress test, we observed the following lockdep warning. This
mean AIO+numa_balancing is currently deadlockable.
The problem is, aio_migratepage disable interrupt, but
__set_page_dirty_nobuffers unintentionally enable it again.
Generally, all helper function should use spin_lock_irqsave() instead of
spin_lock_irq() because they don't know caller at all.
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(&ctx->completion_lock)->rlock);
<Interrupt>
lock(&(&ctx->completion_lock)->rlock);
*** DEADLOCK ***
dump_stack+0x19/0x1b
print_usage_bug+0x1f7/0x208
mark_lock+0x21d/0x2a0
mark_held_locks+0xb9/0x140
trace_hardirqs_on_caller+0x105/0x1d0
trace_hardirqs_on+0xd/0x10
_raw_spin_unlock_irq+0x2c/0x50
__set_page_dirty_nobuffers+0x8c/0xf0
migrate_page_copy+0x434/0x540
aio_migratepage+0xb1/0x140
move_to_new_page+0x7d/0x230
migrate_pages+0x5e5/0x700
migrate_misplaced_page+0xbc/0xf0
do_numa_page+0x102/0x190
handle_pte_fault+0x241/0x970
handle_mm_fault+0x265/0x370
__do_page_fault+0x172/0x5a0
do_page_fault+0x1a/0x70
page_fault+0x28/0x30
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/page-writeback.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 2d30e2cfe804..7106cb1aca8e 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2173,11 +2173,12 @@ int __set_page_dirty_nobuffers(struct page *page) if (!TestSetPageDirty(page)) { struct address_space *mapping = page_mapping(page); struct address_space *mapping2; + unsigned long flags; if (!mapping) return 1; - spin_lock_irq(&mapping->tree_lock); + spin_lock_irqsave(&mapping->tree_lock, flags); mapping2 = page_mapping(page); if (mapping2) { /* Race with truncate? */ BUG_ON(mapping2 != mapping); @@ -2186,7 +2187,7 @@ int __set_page_dirty_nobuffers(struct page *page) radix_tree_tag_set(&mapping->page_tree, page_index(page), PAGECACHE_TAG_DIRTY); } - spin_unlock_irq(&mapping->tree_lock); + spin_unlock_irqrestore(&mapping->tree_lock, flags); if (mapping->host) { /* !PageAnon && !swapper_space */ __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); |