Re: [RFC] deadlock with flush_work() in UAS

2019-07-01 Thread Alan Stern
On Mon, 1 Jul 2019, Oliver Neukum wrote: > Am Mittwoch, den 26.06.2019, 10:38 -0400 schrieb Alan Stern: > > On Wed, 26 Jun 2019, Oliver Neukum wrote: > > > > > Am Montag, den 24.06.2019, 10:22 -0400 schrieb Alan Stern: > > > > But that pattern makes no sense; a driver would never use it. The >

Re: [RFC] deadlock with flush_work() in UAS

2019-07-01 Thread Oliver Neukum
Am Mittwoch, den 26.06.2019, 10:38 -0400 schrieb Alan Stern: > On Wed, 26 Jun 2019, Oliver Neukum wrote: > > > Am Montag, den 24.06.2019, 10:22 -0400 schrieb Alan Stern: > > > But that pattern makes no sense; a driver would never use it. The > > > driver would just do the reset itself. > > > >

Re: [RFC] deadlock with flush_work() in UAS

2019-06-26 Thread Alan Stern
On Wed, 26 Jun 2019, Oliver Neukum wrote: > Am Montag, den 24.06.2019, 10:22 -0400 schrieb Alan Stern: > > But that pattern makes no sense; a driver would never use it. The > > driver would just do the reset itself. > > Correct. But UAS and storage themselves still need to use > WQ_MEM_RECLAIM

Re: [RFC] deadlock with flush_work() in UAS

2019-06-26 Thread Oliver Neukum
Am Montag, den 24.06.2019, 10:22 -0400 schrieb Alan Stern: > But that pattern makes no sense; a driver would never use it. The > driver would just do the reset itself. Correct. But UAS and storage themselves still need to use WQ_MEM_RECLAIM for their workqueues, don't they? Regards

Re: [RFC] deadlock with flush_work() in UAS

2019-06-24 Thread Alan Stern
On Mon, 24 Jun 2019, Oliver Neukum wrote: > Am Donnerstag, den 20.06.2019, 07:10 -0700 schrieb Tejun Heo: > > Hello, > > > > On Tue, Jun 18, 2019 at 11:59:39AM -0400, Alan Stern wrote: > > > > > Even if you disagree, perhaps we should have a global workqueue with a > > > > > permanently set noio

Re: [RFC] deadlock with flush_work() in UAS

2019-06-24 Thread Oliver Neukum
Am Donnerstag, den 20.06.2019, 07:10 -0700 schrieb Tejun Heo: > Hello, > > On Tue, Jun 18, 2019 at 11:59:39AM -0400, Alan Stern wrote: > > > > Even if you disagree, perhaps we should have a global workqueue with a > > > > permanently set noio flag. It could be shared among multiple drivers > > >

Re: [RFC] deadlock with flush_work() in UAS

2019-06-20 Thread Tejun Heo
Hello, On Tue, Jun 18, 2019 at 11:59:39AM -0400, Alan Stern wrote: > > > Even if you disagree, perhaps we should have a global workqueue with a > > > permanently set noio flag. It could be shared among multiple drivers > > > such as uas and the hub driver for purposes like this. (In fact, the >

Re: [RFC] deadlock with flush_work() in UAS

2019-06-18 Thread Alan Stern
Tejun and other workqueue maintainers: On Tue, 18 Jun 2019, Oliver Neukum wrote: > Am Dienstag, den 18.06.2019, 11:29 -0400 schrieb Alan Stern: > > On Tue, 18 Jun 2019, Oliver Neukum wrote: > > > > > Hi, > > > > > > looking at those deadlocks it looks to me like UAS can > > > deadlock on itself