[HACK] fs/super.c: sync ro remount after blocking writers

[Richard Weinberger]

Andrew,

Am 03.02.2014 11:23, schrieb Christoph Hellwig:
> On Thu, Jan 30, 2014 at 09:26:54AM -0600, Andrew Ruder wrote:
>> Move sync_filesystem() after sb_prepare_remount_readonly().  If writers
>> sneak in anywhere from sync_filesystem() to sb_prepare_remount_readonly()
>> it can cause inodes to be dirtied and writeback to occur well after
>> sys_mount() has completely successfully.
>>
>> This was spotted by corrupted ubifs filesystems on reboot, but appears
>> that it can cause issues with any filesystem using writeback.
> 
> From the link that Richard posted it seems like you have a testcase.
> Can you please integrate it into xfstests so that we can properly
> regression test for this issue from now on?

Is it possible to create such a test case?
I don't know whether it is possible to trigger the issue on
a regular filesystem.
But as hch noted, it would be nice to have. :)

Thanks,
//richard