On Sat, Jun 09, 2007 at 03:49:46PM +0900, Tejun Heo wrote: > Tejun Heo wrote: > > Tejun Heo wrote: > >> Greg KH wrote: > >>> On Mon, May 21, 2007 at 10:31:01AM +0530, Maneesh Soni wrote: > >>>> On Thu, May 17, 2007 at 08:16:10PM +0200, Tejun Heo wrote: > >>>>> Allowing attribute and symlink dentries to be reclaimed means > >>>>> sd->s_dentry can change dynamically. However, updates to the field > >>>>> are unsynchronized leading to race conditions. This patch adds > >>>>> sysfs_lock and use it to synchronize updates to sd->s_dentry. > >>>>> > >>>>> Due to the locking around ->d_iput, the check in sysfs_drop_dentry() > >>>>> is complex. sysfs_lock only protect sd->s_dentry pointer itself. The > >>>>> validity of the dentry is protected by dcache_lock, so whether dentry > >>>>> is alive or not can only be tested while holding both locks. > >>>>> > >>>>> This is minimal backport of sysfs_drop_dentry() rewrite in devel > >>>>> branch. > >>>>> > >>>>> DONT APPLY JUST YET > >>>> Looks ok to me.. I have tested it it but unfortunately I couldn't > >>>> recreate the race without the patch also. It would be helpful if > >>>> people actually seeing the race, provide the test results. > >>>> > >>>> Greg, please merge this one once we have some test results. > >>> Can someone just resend it after those test results are in, with the > >>> proper signed-off-by, so I know it's safe to apply? > >> I'll resend with S-O-B after someone verifies it fixes the problem. > > > > Have been trying to reproduce the problem on the latest -rc but haven't > > succeeded yet. It seems I lost my magic recipe for these races. Did > > anyone succeed? > > Alright, overnight test finally hit the race condition. It takes me > much longer now but the race condition is definitely still there. I'll > verify each proposed patch and send it for 2.6.22 inclusion and if > they're accepted to -stable.
Ok, thanks for doing this. greg k-h - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
