The patch titled
drivers/hid: eliminate a double lock
has been added to the -mm tree. Its filename is
drivers-hid-eliminate-a-double-lock.patch
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------------------------------------------------------
Subject: drivers/hid: eliminate a double lock
From: Julia Lawall <julia@xxxxxxx>
The path around the loop ends with the lock held, so the call to mutex_lock
is moved before the beginning of the loop.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@locked@
expression E1;
position p;
@@
read_lock(E1@p,...);
@r exists@
expression x <= locked.E1;
expression locked.E1;
expression E2;
identifier lock;
position locked.p,p1,p2;
@@
*lock@p1 (E1@p,...);
... when != E1
when != \(x = E2\|&x\)
*lock@p2 (E1,...);
// </smpl>
Signed-off-by: Julia Lawall <julia@xxxxxxx>
Cc: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/hid/hid-debug.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN drivers/hid/hid-debug.c~drivers-hid-eliminate-a-double-lock drivers/hid/hid-debug.c
--- a/drivers/hid/hid-debug.c~drivers-hid-eliminate-a-double-lock
+++ a/drivers/hid/hid-debug.c
@@ -949,8 +949,8 @@ static ssize_t hid_debug_events_read(str
int ret = 0, len;
DECLARE_WAITQUEUE(wait, current);
+ mutex_lock(&list->read_mutex);
while (ret == 0) {
- mutex_lock(&list->read_mutex);
if (list->head == list->tail) {
add_wait_queue(&list->hdev->debug_wait, &wait);
set_current_state(TASK_INTERRUPTIBLE);
_
Patches currently in -mm which might be from julia@xxxxxxx are
linux-next.patch
drivers-hid-eliminate-a-double-lock.patch
fs-btrfs-use-memdup_user.patch
fs-btrfs-use-err_cast.patch
drivers-dma-eliminate-a-null-pointer-dereference.patch
drivers-media-use-memdup_user.patch
drivers-media-video-pvrusb2-add-missing-mutex_unlock.patch
drivers-video-omap2-displays-add-missing-mutex_unlock.patch
drivers-s390-net-use-memdup_user.patch
drivers-scsi-libsas-use-sam_good.patch
drivers-scsi-remove-unnecessary-null-test.patch
drivers-message-move-dereference-after-null-test.patch
drivers-scsi-correct-the-size-argument-to-kmalloc.patch
drivers-scsi-use-memdup_user.patch
drivers-block-use-memdup_user.patch
arch-sparc-kernel-eliminate-what-looks-like-a-null-pointer-dereference.patch
mm-use-memdup_user.patch
mm-use-err_cast.patch
drivers-message-i2o-exec-osmc-add-missing-mutex_unlock.patch
drivers-char-n_gsmc-add-missing-spin_unlock_irqrestore.patch
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