Re: [PATCH 2/2] lockdep: check that no locks held at freeze time

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, May 6, 2013 at 12:01 PM, Tejun Heo <tj@xxxxxxxxxx> wrote:
> On Fri, May 03, 2013 at 02:04:10PM -0700, Colin Cross wrote:
>> From: Mandeep Singh Baines <msb@xxxxxxxxxxxx>
>>
>> We shouldn't try_to_freeze if locks are held.  Holding a lock can cause a
>> deadlock if the lock is later acquired in the suspend or hibernate path
>> (e.g.  by dpm).  Holding a lock can also cause a deadlock in the case of
>> cgroup_freezer if a lock is held inside a frozen cgroup that is later
>> acquired by a process outside that group.
>>
>> History:
>> This patch was originally applied as 6aa9707099c and reverted in
>> dbf520a9d7d4 because NFS was freezing with locks held.  It was
>> deemed better to keep the bad freeze point in NFS to allow laptops
>> to suspend consistently.  The previous patch in this series converts
>> NFS to call _unsafe versions of the freezable helpers so that
>> lockdep doesn't complain about them until a more correct fix
>> can be applied.
>
> I don't care about %current change, especially given that it's a debug
> interface but that really should be a separate patch, so please split
> it out if you want it (and I think we want it).

The current change was requested by akpm and was part of the original
patch.  Is it really worth confusing the history of this patch even
more, applying it the first time, reverting it, and then applying it
again in two parts?
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux