Merge tag 'v4.15-rc6' into patchwork

Linux 4.15-rc6

* tag 'v4.15-rc6': (734 commits)
  Linux 4.15-rc6
  MAINTAINERS: mark arch/blackfin/ and its gubbins as orphaned
  x86/ldt: Make LDT pgtable free conditional
  x86/ldt: Plug memory leak in error path
  x86/mm: Remove preempt_disable/enable() from __native_flush_tlb()
  x86/smpboot: Remove stale TLB flush invocations
  objtool: Fix seg fault with clang-compiled objects
  objtool: Fix seg fault caused by missing parameter
  kbuild: add '-fno-stack-check' to kernel build options
  timerqueue: Document return values of timerqueue_add/del()
  timers: Invoke timer_start_debug() where it makes sense
  nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
  timers: Reinitialize per cpu bases on hotplug
  timers: Use deferrable base independent of base::nohz_active
  genirq/msi, x86/vector: Prevent reservation mode for non maskable MSI
  genirq/irqdomain: Rename early argument of irq_domain_activate_irq()
  x86/vector: Use IRQD_CAN_RESERVE flag
  genirq: Introduce IRQD_CAN_RESERVE flag
  genirq/msi: Handle reactivation only on success
  gpio: brcmstb: Make really use of the new lockdep class
  ...

1 files changed, 15 insertions, 5 deletions

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 6249c92671de..a76914db72ef 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -212,6 +212,7 @@ xfs_attr_set(
 	int			flags)
 {
 	struct xfs_mount	*mp = dp->i_mount;
+	struct xfs_buf		*leaf_bp = NULL;
 	struct xfs_da_args	args;
 	struct xfs_defer_ops	dfops;
 	struct xfs_trans_res	tres;
@@ -327,9 +328,16 @@ xfs_attr_set(
 		 * GROT: another possible req'mt for a double-split btree op.
 		 */
 		xfs_defer_init(args.dfops, args.firstblock);
-		error = xfs_attr_shortform_to_leaf(&args);
+		error = xfs_attr_shortform_to_leaf(&args, &leaf_bp);
 		if (error)
 			goto out_defer_cancel;
+		/*
+		 * Prevent the leaf buffer from being unlocked so that a
+		 * concurrent AIL push cannot grab the half-baked leaf
+		 * buffer and run into problems with the write verifier.
+		 */
+		xfs_trans_bhold(args.trans, leaf_bp);
+		xfs_defer_bjoin(args.dfops, leaf_bp);
 		xfs_defer_ijoin(args.dfops, dp);
 		error = xfs_defer_finish(&args.trans, args.dfops);
 		if (error)
@@ -337,13 +345,14 @@ xfs_attr_set(
 
 		/*
 		 * Commit the leaf transformation.  We'll need another (linked)
-		 * transaction to add the new attribute to the leaf.
+		 * transaction to add the new attribute to the leaf, which
+		 * means that we have to hold & join the leaf buffer here too.
 		 */
-
 		error = xfs_trans_roll_inode(&args.trans, dp);
 		if (error)
 			goto out;
-
+		xfs_trans_bjoin(args.trans, leaf_bp);
+		leaf_bp = NULL;
 	}
 
 	if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
@@ -374,8 +383,9 @@ xfs_attr_set(
 
 out_defer_cancel:
 	xfs_defer_cancel(&dfops);
-	args.trans = NULL;
 out:
+	if (leaf_bp)
+		xfs_trans_brelse(args.trans, leaf_bp);
 	if (args.trans)
 		xfs_trans_cancel(args.trans);
 	xfs_iunlock(dp, XFS_ILOCK_EXCL);