From: "Jun'ichi Nomura" <j-nomura@ce.jp.nec.com>
To: Tejun Heo <tj@kernel.org>, Naveen Goswamy <naveen.goswamy@polymtl.ca>
Cc: Jens Axboe <axboe@kernel.dk>,
James Bottomley <James.Bottomley@HansenPartnership.com>,
Stefan Richter <stefanr@s5r6.in-berlin.de>,
Dave Jones <davej@redhat.com>,
linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org
Subject: Re: Kernel crashing on eject SD card
Date: Wed, 15 Feb 2012 11:56:19 +0900 [thread overview]
Message-ID: <4F3B1ED3.4000706@ce.jp.nec.com> (raw)
In-Reply-To: <20120214162858.GM12117@google.com>
Hi,
Thank you for the comments.
On 02/15/12 01:28, Tejun Heo wrote:
>> that could lead to oops like this:
>>
>> process A process B
>> ----------------------------------------------
>> sys_open
>> __blkdev_get
>> sd_open
>> returns -ENOMEDIUM
>> scsi_remove_device
>> <scsi_device torn down>
>> rescan_partitions
>> sd_revalidate_disk
>> <oops>
>>
>> Should "revalidate_disk" of block_device_operations work
>> without successful open()?
>>
>> If so, sd_revalidate_disk() (and possibly other drivers) needs to be
>> fixed. (e.g. use scsi_disk_get/put by itself)
>>
>> If not, __blkdev_get() or rescan_partision() should avoid calling
>> "revalidate_disk" for -ENOMEDIUM case.
>
> Hmmm... right, that's a problem. Missed rescan_partitions() calling
> into driver. What we should probably do is separating out
> invalidation & partition shoot down into a separate function, say
> trucate_disk(), and call that on -ENOMEDIUM instead of
> rescan_partitions(). All that's necessary is killing the partition
> devices (and maybe zapping device size to zero). Any one interested
> in trying it?
How about this?
If the patch looks ok, I appreciate if somebody with removable media
could test the followings:
- the oops in sd_revalidate_disk() should not occur:
http://marc.info/?l=linux-scsi&m=132388619710052
- the problem reported here should not be re-introduced:
https://bugzilla.kernel.org/show_bug.cgi?id=13029
Index: linux-3.3/block/partition-generic.c
===================================================================
--- linux-3.3.orig/block/partition-generic.c 2012-02-15 09:00:25.147293790 +0900
+++ linux-3.3/block/partition-generic.c 2012-02-15 11:31:33.835554974 +0900
@@ -389,17 +389,11 @@ static bool disk_unlock_native_capacity(
}
}
-int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
+static int drop_partitions(struct gendisk *disk, struct block_device *bdev)
{
- struct parsed_partitions *state = NULL;
struct disk_part_iter piter;
struct hd_struct *part;
- int p, highest, res;
-rescan:
- if (state && !IS_ERR(state)) {
- kfree(state);
- state = NULL;
- }
+ int res;
if (bdev->bd_part_count)
return -EBUSY;
@@ -412,6 +406,24 @@ rescan:
delete_partition(disk, part->partno);
disk_part_iter_exit(&piter);
+ return 0;
+}
+
+int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
+{
+ struct parsed_partitions *state = NULL;
+ struct hd_struct *part;
+ int p, highest, res;
+rescan:
+ if (state && !IS_ERR(state)) {
+ kfree(state);
+ state = NULL;
+ }
+
+ res = drop_partitions(disk, bdev);
+ if (res)
+ return res;
+
if (disk->fops->revalidate_disk)
disk->fops->revalidate_disk(disk);
check_disk_size_change(disk, bdev);
@@ -515,6 +527,22 @@ rescan:
return 0;
}
+int invalidate_partitions(struct gendisk *disk, struct block_device *bdev)
+{
+ int res;
+
+ res = drop_partitions(disk, bdev);
+ if (res)
+ return res;
+
+ check_disk_size_change(disk, bdev);
+ bdev->bd_invalidated = 0;
+ /* tell userspace that the media / partition table may have changed */
+ kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
+
+ return 0;
+}
+
unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
{
struct address_space *mapping = bdev->bd_inode->i_mapping;
Index: linux-3.3/include/linux/genhd.h
===================================================================
--- linux-3.3.orig/include/linux/genhd.h 2012-02-09 12:21:53.000000000 +0900
+++ linux-3.3/include/linux/genhd.h 2012-02-15 11:18:59.661594629 +0900
@@ -596,6 +596,7 @@ extern char *disk_name (struct gendisk *
extern int disk_expand_part_tbl(struct gendisk *disk, int target);
extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
+extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
int partno, sector_t start,
sector_t len, int flags,
Index: linux-3.3/fs/block_dev.c
===================================================================
--- linux-3.3.orig/fs/block_dev.c 2012-02-09 12:21:53.000000000 +0900
+++ linux-3.3/fs/block_dev.c 2012-02-15 11:34:48.800549266 +0900
@@ -1183,8 +1183,12 @@ static int __blkdev_get(struct block_dev
* The latter is necessary to prevent ghost
* partitions on a removed medium.
*/
- if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
- rescan_partitions(disk, bdev);
+ if (bdev->bd_invalidated) {
+ if (!ret)
+ rescan_partitions(disk, bdev);
+ else if (ret == -ENOMEDIUM)
+ invalidate_partitions(disk, bdev);
+ }
if (ret)
goto out_clear;
} else {
@@ -1214,8 +1218,12 @@ static int __blkdev_get(struct block_dev
if (bdev->bd_disk->fops->open)
ret = bdev->bd_disk->fops->open(bdev, mode);
/* the same as first opener case, read comment there */
- if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
- rescan_partitions(bdev->bd_disk, bdev);
+ if (bdev->bd_invalidated) {
+ if (!ret)
+ rescan_partitions(bdev->bd_disk, bdev);
+ else if (ret == -ENOMEDIUM)
+ invalidate_partitions(bdev->bd_disk, bdev);
+ }
if (ret)
goto out_unlock_bdev;
}
next prev parent reply other threads:[~2012-02-15 2:57 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-08 0:19 Kernel crashing on eject SD card Naveen Goswamy
2012-02-12 21:08 ` Stefan Richter
2012-02-12 21:20 ` Stefan Richter
2012-02-13 1:46 ` Naveen Goswamy
2012-02-13 2:18 ` Dave Jones
2012-02-13 17:40 ` Naveen Goswamy
2012-02-14 11:14 ` Jun'ichi Nomura
2012-02-14 13:31 ` Stefan Richter
2012-02-14 16:28 ` Tejun Heo
2012-02-15 2:56 ` Jun'ichi Nomura [this message]
2012-02-15 17:26 ` Tejun Heo
2012-02-16 1:26 ` Jun'ichi Nomura
2012-02-16 16:36 ` Tejun Heo
2012-03-01 18:58 ` Luis Henriques
2012-03-02 0:12 ` Jun'ichi Nomura
2012-03-02 9:35 ` Luis Henriques
2012-03-02 9:41 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4F3B1ED3.4000706@ce.jp.nec.com \
--to=j-nomura@ce.jp.nec.com \
--cc=James.Bottomley@HansenPartnership.com \
--cc=axboe@kernel.dk \
--cc=davej@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-scsi@vger.kernel.org \
--cc=naveen.goswamy@polymtl.ca \
--cc=stefanr@s5r6.in-berlin.de \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).