linux-kernel - [PATCH 3.11 035/121] mm: __set_page_dirty_nobuffers() uses spin_lock_irqsave() instead of spin_lock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1392986945-9693-36-git-send-email-luis.henriques@canonical.com>
Date:	Fri, 21 Feb 2014 12:47:39 +0000
From:	Luis Henriques <luis.henriques@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>,
	Larry Woodman <lwoodman@...hat.com>,
	Rik van Riel <riel@...hat.com>,
	Johannes Weiner <jweiner@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Luis Henriques <luis.henriques@...onical.com>
Subject: [PATCH 3.11 035/121] mm: __set_page_dirty_nobuffers() uses spin_lock_irqsave() instead of spin_lock_irq()

3.11.10.5 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>

commit a85d9df1ea1d23682a0ed1e100e6965006595d06 upstream.

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@...fujitsu.com>
Cc: Larry Woodman <lwoodman@...hat.com>
Cc: Rik van Riel <riel@...hat.com>
Cc: Johannes Weiner <jweiner@...hat.com>
Acked-by: David Rientjes <rientjes@...gle.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Luis Henriques <luis.henriques@...onical.com>
---
 mm/page-writeback.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 1c21100..7298e74 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2024,11 +2024,12 @@ 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);
@@ -2037,7 +2038,7 @@ 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);
-- 
1.9.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/