Patch "irda: Fix lockdep annotations in hashbin_delete()." has been added to the 4.4-stable tree
Subsystems (2)
This is a note to let you know that I've just added the patch titled
irda: Fix lockdep annotations in hashbin_delete().
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
irda-fix-lockdep-annotations-in-hashbin_delete.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.
Quoted 1 line
From foo@baz Thu Feb 23 21:13:19 CET 2017
From: "David S. Miller" <[email protected]>
Date: Fri, 17 Feb 2017 16:19:39 -0500
Subject: irda: Fix lockdep annotations in hashbin_delete().
From: "David S. Miller" <[email protected]>
[ Upstream commit 4c03b862b12f980456f9de92db6d508a4999b788 ]
A nested lock depth was added to the hasbin_delete() code but it doesn't actually work some well and results in tons of lockdep splats.
Fix the code instead to properly drop the lock around the operation and just keep peeking the head of the hashbin queue.
--- net/irda/irqueue.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-)
net/irda/irqueue.c +16 -18
@@ -383,9 +383,6 @@ EXPORT_SYMBOL(hashbin_new);* for deallocating this structure if it's complex. If not the user can * just supply kfree, which should take care of the job. */ -#ifdef CONFIG_LOCKDEP -static int hashbin_lock_depth =0 ; -#endif int hashbin_delete (hashbin_t * hashbin,FREE_FUNC free_func) {irda_queue_t * queue;
@@ -396,22 +393,27 @@ int hashbin_delete( hashbin_t* hashbin, IRDA_ASSERT(hashbin->magic == HB_MAGIC, return -1;);/* Synchronize */ -if ( hashbin->hb_type &HB_LOCK ) { -spin_lock_irqsave_nested (&hashbin->hb_spinlock, flags, - hashbin_lock_depth++); - } +if (hashbin->hb_type &HB_LOCK ) +spin_lock_irqsave (&hashbin->hb_spinlock, flags);/* * Free the entries in the hashbin, TODO: use hashbin_clear when * it has been shown to work */ for (i =0 ; i <HASHBIN_SIZE ; i ++ ) { - queue =dequeue_first ((irda_queue_t **) &hashbin->hb_queue[i]); -while (queue ) { -if (free_func) - (*free_func)(queue); - queue =dequeue_first ( - (irda_queue_t **) &hashbin->hb_queue[i]); +while (1 ) { + queue =dequeue_first ((irda_queue_t **) &hashbin->hb_queue[i]); + +if (!queue) +break ; + +if (free_func) { +if (hashbin->hb_type &HB_LOCK ) +spin_unlock_irqrestore (&hashbin->hb_spinlock, flags); +free_func (queue); +if (hashbin->hb_type &HB_LOCK ) +spin_lock_irqsave (&hashbin->hb_spinlock, flags); + } } }
@@ -420,12 +422,8 @@ int hashbin_delete( hashbin_t* hashbin, hashbin->magic = ~HB_MAGIC ;/* Release lock */ -if ( hashbin->hb_type &HB_LOCK ) { +if (hashbin->hb_type &HB_LOCK )spin_unlock_irqrestore (&hashbin->hb_spinlock, flags); -#ifdef CONFIG_LOCKDEP - hashbin_lock_depth--; -#endif - }/* * Free the hashbin structure
Patches currently in stable-queue which might be from [email protected] are
queue-4.4/dccp-fix-freeing-skb-too-early-for-ipv6_recvpktinfo.patch queue-4.4/ip-fix-ip_checksum-handling.patch queue-4.4/irda-fix-lockdep-annotations-in-hashbin_delete.patch queue-4.4/packet-fix-races-in-fanout_add.patch queue-4.4/packet-do-not-call-fanout_release-from-atomic-contexts.patch queue-4.4/net-socket-fix-recvmmsg-not-returning-error-from-sock_error.patch queue-4.4/net-llc-avoid-bug_on-in-skb_orphan.patch