projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| b2af825a GKH |
1 | From foo@baz Thu Feb 23 21:13:05 CET 2017 |
| 2 | From: "David S. Miller" <davem@davemloft.net> | |
| 3 | Date: Fri, 17 Feb 2017 16:19:39 -0500 | |
| 4 | Subject: irda: Fix lockdep annotations in hashbin_delete(). | |
| 5 | ||
| 6 | From: "David S. Miller" <davem@davemloft.net> | |
| 7 | ||
| 8 | ||
| 9 | [ Upstream commit 4c03b862b12f980456f9de92db6d508a4999b788 ] | |
| 10 | ||
| 11 | A nested lock depth was added to the hasbin_delete() code but it | |
| 12 | doesn't actually work some well and results in tons of lockdep splats. | |
| 13 | ||
| 14 | Fix the code instead to properly drop the lock around the operation | |
| 15 | and just keep peeking the head of the hashbin queue. | |
| 16 | ||
| 17 | Reported-by: Dmitry Vyukov <dvyukov@google.com> | |
| 18 | Tested-by: Dmitry Vyukov <dvyukov@google.com> | |
| 19 | Signed-off-by: David S. Miller <davem@davemloft.net> | |
| 20 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 21 | --- | |
| 22 | net/irda/irqueue.c | 34 ++++++++++++++++------------------ | |
| 23 | 1 file changed, 16 insertions(+), 18 deletions(-) | |
| 24 | ||
| 25 | --- a/net/irda/irqueue.c | |
| 26 | +++ b/net/irda/irqueue.c | |
| 27 | @@ -383,9 +383,6 @@ EXPORT_SYMBOL(hashbin_new); | |
| 28 | * for deallocating this structure if it's complex. If not the user can | |
| 29 | * just supply kfree, which should take care of the job. | |
| 30 | */ | |
| 31 | -#ifdef CONFIG_LOCKDEP | |
| 32 | -static int hashbin_lock_depth = 0; | |
| 33 | -#endif | |
| 34 | int hashbin_delete( hashbin_t* hashbin, FREE_FUNC free_func) | |
| 35 | { | |
| 36 | irda_queue_t* queue; | |
| 37 | @@ -396,22 +393,27 @@ int hashbin_delete( hashbin_t* hashbin, | |
| 38 | IRDA_ASSERT(hashbin->magic == HB_MAGIC, return -1;); | |
| 39 | ||
| 40 | /* Synchronize */ | |
| 41 | - if ( hashbin->hb_type & HB_LOCK ) { | |
| 42 | - spin_lock_irqsave_nested(&hashbin->hb_spinlock, flags, | |
| 43 | - hashbin_lock_depth++); | |
| 44 | - } | |
| 45 | + if (hashbin->hb_type & HB_LOCK) | |
| 46 | + spin_lock_irqsave(&hashbin->hb_spinlock, flags); | |
| 47 | ||
| 48 | /* | |
| 49 | * Free the entries in the hashbin, TODO: use hashbin_clear when | |
| 50 | * it has been shown to work | |
| 51 | */ | |
| 52 | for (i = 0; i < HASHBIN_SIZE; i ++ ) { | |
| 53 | - queue = dequeue_first((irda_queue_t**) &hashbin->hb_queue[i]); | |
| 54 | - while (queue ) { | |
| 55 | - if (free_func) | |
| 56 | - (*free_func)(queue); | |
| 57 | - queue = dequeue_first( | |
| 58 | - (irda_queue_t**) &hashbin->hb_queue[i]); | |
| 59 | + while (1) { | |
| 60 | + queue = dequeue_first((irda_queue_t**) &hashbin->hb_queue[i]); | |
| 61 | + | |
| 62 | + if (!queue) | |
| 63 | + break; | |
| 64 | + | |
| 65 | + if (free_func) { | |
| 66 | + if (hashbin->hb_type & HB_LOCK) | |
| 67 | + spin_unlock_irqrestore(&hashbin->hb_spinlock, flags); | |
| 68 | + free_func(queue); | |
| 69 | + if (hashbin->hb_type & HB_LOCK) | |
| 70 | + spin_lock_irqsave(&hashbin->hb_spinlock, flags); | |
| 71 | + } | |
| 72 | } | |
| 73 | } | |
| 74 | ||
| 75 | @@ -420,12 +422,8 @@ int hashbin_delete( hashbin_t* hashbin, | |
| 76 | hashbin->magic = ~HB_MAGIC; | |
| 77 | ||
| 78 | /* Release lock */ | |
| 79 | - if ( hashbin->hb_type & HB_LOCK) { | |
| 80 | + if (hashbin->hb_type & HB_LOCK) | |
| 81 | spin_unlock_irqrestore(&hashbin->hb_spinlock, flags); | |
| 82 | -#ifdef CONFIG_LOCKDEP | |
| 83 | - hashbin_lock_depth--; | |
| 84 | -#endif | |
| 85 | - } | |
| 86 | ||
| 87 | /* | |
| 88 | * Free the hashbin structure |