From: Minchan Kim <minchan@kernel.org>
To: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
Nitin Gupta <ngupta@vflare.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCHv4 00/10] add on-demand device creation
Date: Thu, 7 May 2015 16:41:59 +0900 [thread overview]
Message-ID: <20150507074159.GA3624@blaptop> (raw)
In-Reply-To: <20150507003322.GA4153@swordfish>
On Thu, May 07, 2015 at 09:33:22AM +0900, Sergey Senozhatsky wrote:
> On (05/06/15 17:20), Minchan Kim wrote:
> > I'm fine, too.
> >
> > >
> > >
> > >
> > > can you please test this patch?
> >
> > I tested it and couldn't reproduce it during 5 minutes so it seems
> > we are correct about culpit.
> > However, it's trick and we should find a right way. :)
> >
>
> well, I can't reproduce this race.
>
> btw, just for info. your script does
>
> zram_add
> dd &
> zram_remove
>
> by the time dd starts writing zramX device may be gone, so along with
> block devices we can see regular files in /dev/
>
> [..]
> brw-rw---- 1 root disk 254, 0 May 7 09:16 /dev/zram0
> -rw-r--r-- 1 root root 10485760 May 7 09:17 /dev/zram1
> -rw-r--r-- 1 root root 10485760 May 7 09:20 /dev/zram10
> [..]
>
>
> can you please test thit patch?
Hello Sergey,
Unfortunately, I can reproduce in a few second with this patch.
>
> ---
>
> drivers/block/zram/zram_drv.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
> index e6c4316..1e99d9f 100644
> --- a/drivers/block/zram/zram_drv.c
> +++ b/drivers/block/zram/zram_drv.c
> @@ -1278,6 +1278,8 @@ out_free_dev:
> static int zram_remove(struct zram *zram)
> {
> struct block_device *bdev;
> + struct request_queue *q;
> + int device_id;
>
> bdev = bdget_disk(zram->disk, 0);
> if (!bdev)
> @@ -1306,14 +1308,18 @@ static int zram_remove(struct zram *zram)
> /* Make sure all the pending I/O are finished */
> fsync_bdev(bdev);
> zram_reset_device(zram);
> - bdput(bdev);
> +
> + q = zram->disk->queue;
> + device_id = zram->disk->first_minor;
>
> pr_info("Removed device: %s\n", zram->disk->disk_name);
>
> - idr_remove(&zram_index_idr, zram->disk->first_minor);
> - blk_cleanup_queue(zram->disk->queue);
> del_gendisk(zram->disk);
> put_disk(zram->disk);
> + blk_cleanup_queue(q);
> + bdput(bdev);
> +
> + idr_remove(&zram_index_idr, device_id);
> kfree(zram);
> return 0;
> }
--
Kind regards,
Minchan Kim
next prev parent reply other threads:[~2015-05-07 7:42 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-04 12:38 [PATCHv4 00/10] add on-demand device creation Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 01/10] zram: add `compact` sysfs entry to documentation Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 02/10] zram: cosmetic ZRAM_ATTR_RO code formatting tweak Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 03/10] zram: use idr instead of `zram_devices' array Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 04/10] zram: reorganize code layout Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 05/10] zram: remove max_num_devices limitation Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 06/10] zram: report every added and removed device Sergey Senozhatsky
2015-05-04 12:38 ` [PATCHv4 07/10] zram: trivial: correct flag operations comment Sergey Senozhatsky
2015-05-04 12:39 ` [PATCHv4 08/10] zram: return zram device_id from zram_add() Sergey Senozhatsky
2015-05-04 12:39 ` [PATCHv4 09/10] zram: close race by open overriding Sergey Senozhatsky
2015-05-04 12:39 ` [PATCHv4 10/10] zram: add dynamic device add/remove functionality Sergey Senozhatsky
2015-05-06 5:01 ` [PATCHv4 00/10] add on-demand device creation Minchan Kim
2015-05-06 5:25 ` Sergey Senozhatsky
2015-05-06 6:52 ` Minchan Kim
2015-05-06 7:07 ` Sergey Senozhatsky
2015-05-06 7:28 ` Minchan Kim
2015-05-06 8:10 ` Sergey Senozhatsky
2015-05-06 8:20 ` Minchan Kim
2015-05-07 0:33 ` Sergey Senozhatsky
2015-05-07 7:41 ` Minchan Kim [this message]
2015-05-07 12:09 ` Sergey Senozhatsky
2015-05-07 13:04 ` Sergey Senozhatsky
2015-05-07 15:11 ` Minchan Kim
2015-05-08 0:15 ` Sergey Senozhatsky
2015-05-10 8:47 ` Sergey Senozhatsky
2015-05-06 5:31 ` Sergey Senozhatsky
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