On Tue, Sep 25, 2018 at 08:14:45AM -0700, Bart Van Assche wrote:
> On Tue, 2018-09-25 at 08:39 -0600, Keith Busch wrote:
> > On Tue, Sep 25, 2018 at 10:39:46AM +0800, jianchao.wang wrote:
> > > But the issue is the left part of blk_mq_timeout_work is moved out of
> > > protection of q refcount.
>
On Tue, 2018-09-25 at 08:39 -0600, Keith Busch wrote:
> On Tue, Sep 25, 2018 at 10:39:46AM +0800, jianchao.wang wrote:
> > But the issue is the left part of blk_mq_timeout_work is moved out of
> > protection of q refcount.
>
> I'm not sure what you mean by "left part". The only part that isn't
>
On Tue, Sep 25, 2018 at 10:39:46AM +0800, jianchao.wang wrote:
> Hi Bart
>
> On 09/25/2018 10:20 AM, Bart Van Assche wrote:
> > On 9/24/18 7:11 PM, jianchao.wang wrote:
> >> Hi Keith
> >>
> >> On 09/25/2018 05:09 AM, Keith Busch wrote:
> >>> - /* A deadlock might occur if a request is stuck
Hi Bart
On 09/25/2018 10:20 AM, Bart Van Assche wrote:
> On 9/24/18 7:11 PM, jianchao.wang wrote:
>> Hi Keith
>>
>> On 09/25/2018 05:09 AM, Keith Busch wrote:
>>> - /* A deadlock might occur if a request is stuck requiring a
>>> - * timeout at the same time a queue freeze is waiting
>>> -
On 9/24/18 7:11 PM, jianchao.wang wrote:
Hi Keith
On 09/25/2018 05:09 AM, Keith Busch wrote:
- /* A deadlock might occur if a request is stuck requiring a
-* timeout at the same time a queue freeze is waiting
-* completion, since the timeout code would not be able to
-
Hi Keith
On 09/25/2018 05:09 AM, Keith Busch wrote:
> - /* A deadlock might occur if a request is stuck requiring a
> - * timeout at the same time a queue freeze is waiting
> - * completion, since the timeout code would not be able to
> - * acquire the queue reference here.
> -
A recent commit had tag iterator callbacks run under the rcu read
lock. Existing callbacks exist that do not satisy the rcu non-blocking
requirement.
The commit intended to prevent an iterator from accessing a queue that's
being modified. This patch fixes the original issue by taking a queue
