Re: [PATCH] XFS fix remount rw with unrecognized options

From: Jianjun Kong
Date: Thu Oct 16 2008 - 10:08:18 EST


On Thu, Oct 16, 2008 at 03:55:49PM +0200, Klaus Strebel wrote:
>Jianjun Kong schrieb:
>> On Thu, Oct 16, 2008 at 11:29:26AM +1100, Tim Shimmin wrote:
>>> Resending as I mangled sending the mail from home last time. Sorry.
>>>
>>> Please include the following patch for 2.6.27.1 stable release as
>>> suggested by Christoph Hellwig and Eric Sandeen.
>>> It fixes a regression in the recent remount recoding
>>> where remounting say from ro to rw allows the xfs flags to
>>> be out of sync with the vfs flags, resulting
>>> in failures for some programs such as touch (which end up calling xfs_setattr).
>>> The fix is a very minor and clear.
>>>
>>> Thanks,
>>> Tim.
>>>
>>> Date: Sun, 12 Oct 2008 14:30:44 +0200
>>> From: Christoph Hellwig <hch@xxxxxx>
>>> To: xfs@xxxxxxxxxxx
>>> Subject: [PATCH] fix remount rw with unrecognized options
>>>
>>> When we skip unrecognized options in xfs_fs_remount we should just break
>>> out of the switch and not return because otherwise we may skip clearing
>>> the xfs-internal read-only flag. This will only show up on some
>>> operations like touch because most read-only checks are done by the VFS
>>> which thinks this filesystem is r/w. Eventually we should replace the
>>> XFS read-only flag with a helper that always checks the VFS flag to make
>>> sure they can never get out of sync.
>>>
>>> Bug reported and fix verified by Marcel Beister on #xfs.
>>> Bug fix verified by updated xfstests/189.
>>>
>>> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
>>> Acked-by: Eric Sandeen <sandeen@xxxxxxxxxxx>
>>> Signed-off-by: Timothy Shimmin <tes@xxxxxxx>
>>>
>>> Index: mainline/fs/xfs/linux-2.6/xfs_super.c
>>> ===================================================================
>>> --- mainline.orig/fs/xfs/linux-2.6/xfs_super.c 2008-10-15 17:59:26.542652847 +1100
>>> +++ mainline/fs/xfs/linux-2.6/xfs_super.c 2008-10-15 17:59:45.376217172 +1100
>>> @@ -1323,7 +1323,7 @@ xfs_fs_remount(
>>> "XFS: mount option \"%s\" not supported for remount\n", p);
>>> return -EINVAL;
>>> #else
>>> - return 0;
>>> + break;
>>> #endif

<....>
>> Signed-off-by: Jianjun Kong <kongjianjun@xxxxxxxxx>
>> ---
>> fs/xfs/linux-2.6/xfs_super.c | 7 +------
>> 1 files changed, 1 insertions(+), 6 deletions(-)
>>
>> diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
>> index e390136..bd5ec81 100644
>> --- a/fs/xfs/linux-2.6/xfs_super.c
>> +++ b/fs/xfs/linux-2.6/xfs_super.c
>> @@ -1318,12 +1318,7 @@ xfs_fs_remount(
>> * every remount request, and silently ignore all
>> * options that we can't actually change.
>> */
>> -#if 0
>> - printk(KERN_INFO
>> - "XFS: mount option \"%s\" not supported for remount\n", p);
>> - return -EINVAL;
>> -#else
>> - break;
>> + break 0;
>> #endif
>> }
>> }
>I see my compilers error message '"#endif" without corresponding "#if"'
>and i think he'll also dislike the 'break 0;' ... 'missing ";" before
>"0" in line xxx' ;-).

Sorry. another one :)

Signed-off-by: Jianjun Kong <kongjianjun@xxxxxxxxx>
---
fs/xfs/linux-2.6/xfs_super.c | 8 +-------
1 files changed, 1 insertions(+), 7 deletions(-)

diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index e390136..c019f78 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -1318,13 +1318,7 @@ xfs_fs_remount(
* every remount request, and silently ignore all
* options that we can't actually change.
*/
-#if 0
- printk(KERN_INFO
- "XFS: mount option \"%s\" not supported for remount\n", p);
- return -EINVAL;
-#else
- break;
-#endif
+ break ;
}
}

--
1.5.2.5



--
Jianjun Kong | Happy Hacking
HomePage: http://kongove.cn
Gtalk: kongjianjun@xxxxxxxxx
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