Re: [PATCH 5.0 19/93] paride/pcd: cleanup queues when detection fails

[nobuhiro1.iwamatsu]

Hi,

> [ Upstream commit 81b74ac68c28fddb3589ad5d4d5e587baf4bb781 ]
> 
> The driver allocates queues for all the units it potentially
> supports. But if we fail to detect any drives, then we fail
> loading the module without cleaning up those queues. This is
> now evident with the switch to blk-mq, though the bug has
> been there forever as far as I can tell.
> 
> Also fix cleanup through regular module exit.
> 
> Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

This commit causes a new problem. And the commit that made the fix
is f0d1762554014ce0ae347b9f0d088f2c157c8c72.
I think this commit needs to be applied together.

Best regards,
  Nobuhiro

________________________________________
差出人: stable-owner@xxxxxxxxxxxxxxx <stable-owner@xxxxxxxxxxxxxxx> が Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> の代理で送信
送信日時: 2019年4月19日 2:56
宛先: linux-kernel@xxxxxxxxxxxxxxx
CC: Greg Kroah-Hartman; stable@xxxxxxxxxxxxxxx; Randy Dunlap; Jens Axboe; Sasha Levin
件名: [PATCH 5.0 19/93] paride/pcd: cleanup queues when detection fails

[ Upstream commit 81b74ac68c28fddb3589ad5d4d5e587baf4bb781 ]

The driver allocates queues for all the units it potentially
supports. But if we fail to detect any drives, then we fail
loading the module without cleaning up those queues. This is
now evident with the switch to blk-mq, though the bug has
been there forever as far as I can tell.

Also fix cleanup through regular module exit.

Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/block/paride/pcd.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index 96670eefaeb2..377a694dc228 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -749,8 +749,12 @@ static int pcd_detect(void)
                return 0;

        printk("%s: No CD-ROM drive found\n", name);
-       for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++)
+       for (unit = 0, cd = pcd; unit < PCD_UNITS; unit++, cd++) {
+               blk_cleanup_queue(cd->disk->queue);
+               cd->disk->queue = NULL;
+               blk_mq_free_tag_set(&cd->tag_set);
                put_disk(cd->disk);
+       }
        pi_unregister_driver(par_drv);
        return -1;
 }
--
2.19.1