Linux v3.14-4555-gb33ce4429938

btrfs-fix-lockdep-warning-with-reclaim-lock-inversion.patch

@@ -0,0 +1,79 @@
+From patchwork Wed Mar 26 18:11:26 2014
+Content-Type: text/plain; charset="utf-8"
+MIME-Version: 1.0
+Content-Transfer-Encoding: 7bit
+Subject: btrfs: fix lockdep warning with reclaim lock inversion
+From: Jeff Mahoney <jeffm@suse.com>
+X-Patchwork-Id: 3894781
+Message-Id: <5333184E.3090609@suse.com>
+To: linux-btrfs <linux-btrfs@vger.kernel.org>
+Date: Wed, 26 Mar 2014 14:11:26 -0400
+
+When encountering memory pressure, testers have run into the following
+lockdep warning. It was caused by __link_block_group calling kobject_add
+with the groups_sem held. kobject_add calls kvasprintf with GFP_KERNEL,
+which gets us into reclaim context. The kobject doesn't actually need
+to be added under the lock -- it just needs to ensure that it's only
+added for the first block group to be linked.
+
+
+=========================================================
+[ INFO: possible irq lock inversion dependency detected ]
+3.14.0-rc8-default #1 Not tainted
+---------------------------------------------------------
+kswapd0/169 just changed the state of lock:
+ (&delayed_node->mutex){+.+.-.}, at: [<ffffffffa018baea>] __btrfs_release_delayed_node+0x3a/0x200 [btrfs]
+but this lock took another, RECLAIM_FS-unsafe lock in the past:
+ (&found->groups_sem){+++++.}
+
+and interrupts could create inverse lock ordering between them.
+
+other info that might help us debug this:
+ Possible interrupt unsafe locking scenario:
+       CPU0                    CPU1
+       ----                    ----
+  lock(&found->groups_sem);
+                               local_irq_disable();
+                               lock(&delayed_node->mutex);
+                               lock(&found->groups_sem);
+  <Interrupt>
+    lock(&delayed_node->mutex);
+
+ *** DEADLOCK ***
+2 locks held by kswapd0/169:
+ #0:  (shrinker_rwsem){++++..}, at: [<ffffffff81159e8a>] shrink_slab+0x3a/0x160
+ #1:  (&type->s_umount_key#27){++++..}, at: [<ffffffff811bac6f>] grab_super_passive+0x3f/0x90
+
+Signed-off-by: Jeff Mahoney <jeffm@suse.com>
+---
+ fs/btrfs/extent-tree.c |   10 +++++++---
+ 1 file changed, 7 insertions(+), 3 deletions(-)
+
+--- a/fs/btrfs/extent-tree.c
++++ b/fs/btrfs/extent-tree.c
+@@ -8343,9 +8343,15 @@ static void __link_block_group(struct bt
+ 			       struct btrfs_block_group_cache *cache)
+ {
+ 	int index = get_block_group_index(cache);
++	bool first = false;
+ 
+ 	down_write(&space_info->groups_sem);
+-	if (list_empty(&space_info->block_groups[index])) {
++	if (list_empty(&space_info->block_groups[index]))
++		first = true;
++	list_add_tail(&cache->list, &space_info->block_groups[index]);
++	up_write(&space_info->groups_sem);
++
++	if (first) {
+ 		struct kobject *kobj = &space_info->block_group_kobjs[index];
+ 		int ret;
+ 
+@@ -8357,8 +8363,6 @@ static void __link_block_group(struct bt
+ 			kobject_put(&space_info->kobj);
+ 		}
+ 	}
+-	list_add_tail(&cache->list, &space_info->block_groups[index]);
+-	up_write(&space_info->groups_sem);
+ }
+ 
+ static struct btrfs_block_group_cache *

kernel.spec

@@ -61,7 +61,7 @@ Summary: The Linux kernel
 # The rc snapshot level
 %define rcrev 0
 # The git snapshot level
-%define gitrev 4
+%define gitrev 5
 # Set rpm version accordingly
 %define rpmversion 3.%{upstream_sublevel}.0
 %endif
@@ -652,6 +652,7 @@ Patch25055: net-enic-include-irq.h-for-irqreturn_t-definitions.patch
 Patch25056: net-bnx2x-include-irq.h-for-irqreturn_t-definitions.patch
 Patch25057: net-qlcnic-include-irq.h-for-irq-definitions.patch
 Patch25058: arm64-Fix-duplicated-Kconfig-entries-again.patch
+Patch25059: btrfs-fix-lockdep-warning-with-reclaim-lock-inversion.patch
 
 # END OF PATCH DEFINITIONS
 
@@ -1310,6 +1311,7 @@ ApplyPatch net-enic-include-irq.h-for-irqreturn_t-definitions.patch
 ApplyPatch net-bnx2x-include-irq.h-for-irqreturn_t-definitions.patch
 ApplyPatch net-qlcnic-include-irq.h-for-irq-definitions.patch
 ApplyPatch arm64-Fix-duplicated-Kconfig-entries-again.patch
+ApplyPatch btrfs-fix-lockdep-warning-with-reclaim-lock-inversion.patch
 
 # END OF PATCH APPLICATIONS
 
@@ -2090,6 +2092,9 @@ fi
 #                                    ||----w |
 #                                    ||     ||
 %changelog
+* Wed Apr 02 2014 Josh Boyer <jwboyer@fedoraproject.org> - 3.15.0-0.rc0.git5.1
+- Linux v3.14-4555-gb33ce4429938
+
 * Wed Apr 02 2014 Josh Boyer <jwboyer@fedoraproject.org> - 3.15.0-0.rc0.git4.1
 - Linux v3.14-4227-g3e75c6de1ac3
 

sources

@@ -1,3 +1,3 @@
 b621207b3f6ecbb67db18b13258f8ea8  linux-3.14.tar.xz
 d36baf2d62de5aa61f10a976d00d2d2a  perf-man-3.14.tar.gz
-7609c832bc217f3132fa9b6b5d55e7bb  patch-3.14-git4.xz
+c8298b428fcee237f73c054d11859117  patch-3.14-git5.xz