From 6b73e4c06d326571589eebcb78efde6182330042 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Tue, 10 May 2011 07:53:48 -0700 Subject: [PATCH] Staging: hv: blkvsc_drv: Cleanup spin lock usage This spin lock is potentially acquired from interrupt context. Ensure that the interrupts are blocked whenever the lock is held. The current code was not consistent with regards to blocking interrupts - the same lock would be acquired without blocking interrupts in some instance while the interrupts would be blocked in other instances. Fix this potential deadlock problem. Signed-off-by: K. Y. Srinivasan Signed-off-by: Haiyang Zhang Signed-off-by: Abhishek Kane Signed-off-by: Hank Janssen Signed-off-by: Greg Kroah-Hartman --- drivers/staging/hv/blkvsc_drv.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/staging/hv/blkvsc_drv.c b/drivers/staging/hv/blkvsc_drv.c index cfef1c0bfb39..74d51bb78701 100644 --- a/drivers/staging/hv/blkvsc_drv.c +++ b/drivers/staging/hv/blkvsc_drv.c @@ -249,12 +249,13 @@ static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req, static int blkvsc_open(struct block_device *bdev, fmode_t mode) { struct block_device_context *blkdev = bdev->bd_disk->private_data; + unsigned long flags; - spin_lock(&blkdev->lock); + spin_lock_irqsave(&blkdev->lock, flags); blkdev->users++; - spin_unlock(&blkdev->lock); + spin_unlock_irqrestore(&blkdev->lock, flags); return 0; } @@ -616,17 +617,18 @@ static void blkvsc_shutdown(struct hv_device *dev) static int blkvsc_release(struct gendisk *disk, fmode_t mode) { struct block_device_context *blkdev = disk->private_data; + unsigned long flags; - spin_lock(&blkdev->lock); + spin_lock_irqsave(&blkdev->lock, flags); if (blkdev->users == 1) { - spin_unlock(&blkdev->lock); + spin_unlock_irqrestore(&blkdev->lock, flags); blkvsc_do_operation(blkdev, DO_FLUSH); - spin_lock(&blkdev->lock); + spin_lock_irqsave(&blkdev->lock, flags); } blkdev->users--; - spin_unlock(&blkdev->lock); + spin_unlock_irqrestore(&blkdev->lock, flags); return 0; } -- 2.30.2