diff mbox series

mmc: Fix tag set memory leak

Message ID 20190502190714.181664-1-rrangel@chromium.org (mailing list archive)
State New, archived
Headers show
Series mmc: Fix tag set memory leak | expand

Commit Message

Raul Rangel May 2, 2019, 7:07 p.m. UTC
The tag set is allocated in mmc_init_queue but never freed. This results
in a memory leak. This change makes sure we free the tag set when the
queue is also freed.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
---
I found this using kmemleak and plugging and unplugging an SD card in a
few times.

Here is an example of the output of kmemleak:
unreferenced object 0xffff888125be4ce8 (size 8):
  comm "kworker/1:0", pid 17, jiffies 4294901575 (age 204.773s)
  hex dump (first 8 bytes):
    00 00 00 00 00 00 00 00                          ........
  backtrace:
    [<0000000061cb8887>] blk_mq_alloc_tag_set+0xe9/0x234
    [<00000000cf532a0f>] mmc_init_queue+0xa9/0x2f0
    [<000000001e085171>] mmc_blk_alloc_req+0x125/0x2f9
    [<00000000eae1bd01>] mmc_blk_probe+0x1e2/0x6c1
    [<00000000a0b4a87d>] really_probe+0x1bd/0x3b0
    [<00000000e58f3eb9>] driver_probe_device+0xe1/0x115
    [<00000000358f3b3c>] bus_for_each_drv+0x89/0xac
    [<00000000ef52ccbe>] __device_attach+0xb0/0x14a
    [<00000000c9daafa7>] bus_probe_device+0x33/0x9f
    [<0000000008ac5779>] device_add+0x34b/0x5e2
    [<00000000b42623cc>] mmc_add_card+0x1f5/0x20d
    [<00000000f114ebc3>] mmc_attach_sd+0xc5/0x14b
    [<000000006e915e0d>] mmc_rescan+0x261/0x2b6
    [<00000000e5b49c26>] process_one_work+0x1d3/0x31f
    [<0000000068c8cd3c>] worker_thread+0x1cd/0x2bf
    [<00000000326e2e22>] kthread+0x14f/0x157

Once I applied this patch the leak went away.

p.s., I included a small white space fix. Hope that's ok.

 drivers/mmc/core/queue.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Jens Axboe May 2, 2019, 8:11 p.m. UTC | #1
On 5/2/19 1:07 PM, Raul E Rangel wrote:
> The tag set is allocated in mmc_init_queue but never freed. This results
> in a memory leak. This change makes sure we free the tag set when the
> queue is also freed.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Adrian Hunter May 3, 2019, 6:29 a.m. UTC | #2
On 2/05/19 10:07 PM, Raul E Rangel wrote:
> The tag set is allocated in mmc_init_queue but never freed. This results
> in a memory leak. This change makes sure we free the tag set when the
> queue is also freed.
> 
> Signed-off-by: Raul E Rangel <rrangel@chromium.org>

One comment below, otherwise:

Fixes: 81196976ed94 ("mmc: block: Add blk-mq support")
Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
> I found this using kmemleak and plugging and unplugging an SD card in a
> few times.
> 
> Here is an example of the output of kmemleak:
> unreferenced object 0xffff888125be4ce8 (size 8):
>   comm "kworker/1:0", pid 17, jiffies 4294901575 (age 204.773s)
>   hex dump (first 8 bytes):
>     00 00 00 00 00 00 00 00                          ........
>   backtrace:
>     [<0000000061cb8887>] blk_mq_alloc_tag_set+0xe9/0x234
>     [<00000000cf532a0f>] mmc_init_queue+0xa9/0x2f0
>     [<000000001e085171>] mmc_blk_alloc_req+0x125/0x2f9
>     [<00000000eae1bd01>] mmc_blk_probe+0x1e2/0x6c1
>     [<00000000a0b4a87d>] really_probe+0x1bd/0x3b0
>     [<00000000e58f3eb9>] driver_probe_device+0xe1/0x115
>     [<00000000358f3b3c>] bus_for_each_drv+0x89/0xac
>     [<00000000ef52ccbe>] __device_attach+0xb0/0x14a
>     [<00000000c9daafa7>] bus_probe_device+0x33/0x9f
>     [<0000000008ac5779>] device_add+0x34b/0x5e2
>     [<00000000b42623cc>] mmc_add_card+0x1f5/0x20d
>     [<00000000f114ebc3>] mmc_attach_sd+0xc5/0x14b
>     [<000000006e915e0d>] mmc_rescan+0x261/0x2b6
>     [<00000000e5b49c26>] process_one_work+0x1d3/0x31f
>     [<0000000068c8cd3c>] worker_thread+0x1cd/0x2bf
>     [<00000000326e2e22>] kthread+0x14f/0x157
> 
> Once I applied this patch the leak went away.
> 
> p.s., I included a small white space fix. Hope that's ok.

Not really.  For example, the patch does not apply cleanly to stable trees
only because of that chunk.

> 
>  drivers/mmc/core/queue.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
> index 7c364a9c4eeb..176a08748cf1 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -402,7 +402,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
>  
>  	mq->card = card;
>  	mq->use_cqe = host->cqe_enabled;
> -	
> +
>  	spin_lock_init(&mq->lock);
>  
>  	memset(&mq->tag_set, 0, sizeof(mq->tag_set));
> @@ -472,6 +472,7 @@ void mmc_cleanup_queue(struct mmc_queue *mq)
>  		blk_mq_unquiesce_queue(q);
>  
>  	blk_cleanup_queue(q);
> +	blk_mq_free_tag_set(&mq->tag_set);
>  
>  	/*
>  	 * A request can be completed before the next request, potentially
>
Ulf Hansson May 3, 2019, 10:06 a.m. UTC | #3
On Thu, 2 May 2019 at 21:07, Raul E Rangel <rrangel@chromium.org> wrote:
>
> The tag set is allocated in mmc_init_queue but never freed. This results
> in a memory leak. This change makes sure we free the tag set when the
> queue is also freed.
>
> Signed-off-by: Raul E Rangel <rrangel@chromium.org>

Applied for fixes (it may not make it for v5.1 unless there is a rc8), thanks!

I also dropped the white space fixup, for the reasons explained by Adrian.

Kind regards
Uffe

> ---
> I found this using kmemleak and plugging and unplugging an SD card in a
> few times.
>
> Here is an example of the output of kmemleak:
> unreferenced object 0xffff888125be4ce8 (size 8):
>   comm "kworker/1:0", pid 17, jiffies 4294901575 (age 204.773s)
>   hex dump (first 8 bytes):
>     00 00 00 00 00 00 00 00                          ........
>   backtrace:
>     [<0000000061cb8887>] blk_mq_alloc_tag_set+0xe9/0x234
>     [<00000000cf532a0f>] mmc_init_queue+0xa9/0x2f0
>     [<000000001e085171>] mmc_blk_alloc_req+0x125/0x2f9
>     [<00000000eae1bd01>] mmc_blk_probe+0x1e2/0x6c1
>     [<00000000a0b4a87d>] really_probe+0x1bd/0x3b0
>     [<00000000e58f3eb9>] driver_probe_device+0xe1/0x115
>     [<00000000358f3b3c>] bus_for_each_drv+0x89/0xac
>     [<00000000ef52ccbe>] __device_attach+0xb0/0x14a
>     [<00000000c9daafa7>] bus_probe_device+0x33/0x9f
>     [<0000000008ac5779>] device_add+0x34b/0x5e2
>     [<00000000b42623cc>] mmc_add_card+0x1f5/0x20d
>     [<00000000f114ebc3>] mmc_attach_sd+0xc5/0x14b
>     [<000000006e915e0d>] mmc_rescan+0x261/0x2b6
>     [<00000000e5b49c26>] process_one_work+0x1d3/0x31f
>     [<0000000068c8cd3c>] worker_thread+0x1cd/0x2bf
>     [<00000000326e2e22>] kthread+0x14f/0x157
>
> Once I applied this patch the leak went away.
>
> p.s., I included a small white space fix. Hope that's ok.
>
>  drivers/mmc/core/queue.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
> index 7c364a9c4eeb..176a08748cf1 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -402,7 +402,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
>
>         mq->card = card;
>         mq->use_cqe = host->cqe_enabled;
> -
> +
>         spin_lock_init(&mq->lock);
>
>         memset(&mq->tag_set, 0, sizeof(mq->tag_set));
> @@ -472,6 +472,7 @@ void mmc_cleanup_queue(struct mmc_queue *mq)
>                 blk_mq_unquiesce_queue(q);
>
>         blk_cleanup_queue(q);
> +       blk_mq_free_tag_set(&mq->tag_set);
>
>         /*
>          * A request can be completed before the next request, potentially
> --
> 2.21.0.593.g511ec345e18-goog
>
diff mbox series

Patch

diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index 7c364a9c4eeb..176a08748cf1 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -402,7 +402,7 @@  int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card)
 
 	mq->card = card;
 	mq->use_cqe = host->cqe_enabled;
-	
+
 	spin_lock_init(&mq->lock);
 
 	memset(&mq->tag_set, 0, sizeof(mq->tag_set));
@@ -472,6 +472,7 @@  void mmc_cleanup_queue(struct mmc_queue *mq)
 		blk_mq_unquiesce_queue(q);
 
 	blk_cleanup_queue(q);
+	blk_mq_free_tag_set(&mq->tag_set);
 
 	/*
 	 * A request can be completed before the next request, potentially