Re: possible deadlock in sk_clone_lock

2021-03-05 Thread Michal Hocko
On Tue 02-03-21 19:59:22, Shakeel Butt wrote: > On Tue, Mar 2, 2021 at 1:19 PM Mike Kravetz wrote: > > > > On 3/2/21 6:29 AM, Michal Hocko wrote: > > > On Tue 02-03-21 06:11:51, Shakeel Butt wrote: > > >> On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > > >>> > > >>> On Mon 01-03-21 17:16:29,

Re: possible deadlock in sk_clone_lock

2021-03-04 Thread Michal Hocko
On Wed 03-03-21 09:59:45, Paul E. McKenney wrote: > On Wed, Mar 03, 2021 at 09:03:27AM +0100, Michal Hocko wrote: [...] > > Paul what is the current plan with in_atomic to be usable for !PREEMPT > > configurations? > > Ah, thank you for the reminder! I have rebased that series on top of > v5.12-r

Re: possible deadlock in sk_clone_lock

2021-03-03 Thread Paul E. McKenney
On Wed, Mar 03, 2021 at 09:03:27AM +0100, Michal Hocko wrote: > [Add Paul] > > On Tue 02-03-21 13:19:34, Mike Kravetz wrote: > > On 3/2/21 6:29 AM, Michal Hocko wrote: > > > On Tue 02-03-21 06:11:51, Shakeel Butt wrote: > > >> On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > > >>> > > >>> On

Re: possible deadlock in sk_clone_lock

2021-03-03 Thread Michal Hocko
[Add Paul] On Tue 02-03-21 13:19:34, Mike Kravetz wrote: > On 3/2/21 6:29 AM, Michal Hocko wrote: > > On Tue 02-03-21 06:11:51, Shakeel Butt wrote: > >> On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > >>> > >>> On Mon 01-03-21 17:16:29, Mike Kravetz wrote: > On 3/1/21 9:23 AM, Michal Ho

Re: possible deadlock in sk_clone_lock

2021-03-03 Thread Shakeel Butt
On Tue, Mar 2, 2021 at 1:19 PM Mike Kravetz wrote: > > On 3/2/21 6:29 AM, Michal Hocko wrote: > > On Tue 02-03-21 06:11:51, Shakeel Butt wrote: > >> On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > >>> > >>> On Mon 01-03-21 17:16:29, Mike Kravetz wrote: > On 3/1/21 9:23 AM, Michal Hocko

Re: possible deadlock in sk_clone_lock

2021-03-02 Thread Mike Kravetz
On 3/2/21 6:29 AM, Michal Hocko wrote: > On Tue 02-03-21 06:11:51, Shakeel Butt wrote: >> On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: >>> >>> On Mon 01-03-21 17:16:29, Mike Kravetz wrote: On 3/1/21 9:23 AM, Michal Hocko wrote: > On Mon 01-03-21 08:39:22, Shakeel Butt wrote: >>

Re: possible deadlock in sk_clone_lock

2021-03-02 Thread Michal Hocko
On Tue 02-03-21 06:11:51, Shakeel Butt wrote: > On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > > > > On Mon 01-03-21 17:16:29, Mike Kravetz wrote: > > > On 3/1/21 9:23 AM, Michal Hocko wrote: > > > > On Mon 01-03-21 08:39:22, Shakeel Butt wrote: > > > >> On Mon, Mar 1, 2021 at 7:57 AM Michal

Re: possible deadlock in sk_clone_lock

2021-03-02 Thread Shakeel Butt
On Tue, Mar 2, 2021 at 1:44 AM Michal Hocko wrote: > > On Mon 01-03-21 17:16:29, Mike Kravetz wrote: > > On 3/1/21 9:23 AM, Michal Hocko wrote: > > > On Mon 01-03-21 08:39:22, Shakeel Butt wrote: > > >> On Mon, Mar 1, 2021 at 7:57 AM Michal Hocko wrote: > > > [...] > > >>> Then how come this can

Re: possible deadlock in sk_clone_lock

2021-03-02 Thread Michal Hocko
On Mon 01-03-21 17:16:29, Mike Kravetz wrote: > On 3/1/21 9:23 AM, Michal Hocko wrote: > > On Mon 01-03-21 08:39:22, Shakeel Butt wrote: > >> On Mon, Mar 1, 2021 at 7:57 AM Michal Hocko wrote: > > [...] > >>> Then how come this can ever be a problem? in_task() should exclude soft > >>> irq context

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Mike Kravetz
On 3/1/21 9:23 AM, Michal Hocko wrote: > On Mon 01-03-21 08:39:22, Shakeel Butt wrote: >> On Mon, Mar 1, 2021 at 7:57 AM Michal Hocko wrote: > [...] >>> Then how come this can ever be a problem? in_task() should exclude soft >>> irq context unless I am mistaken. >>> >> >> If I take the following e

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Michal Hocko
On Mon 01-03-21 08:39:22, Shakeel Butt wrote: > On Mon, Mar 1, 2021 at 7:57 AM Michal Hocko wrote: [...] > > Then how come this can ever be a problem? in_task() should exclude soft > > irq context unless I am mistaken. > > > > If I take the following example of syzbot's deadlock scenario then > C

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Shakeel Butt
On Mon, Mar 1, 2021 at 7:57 AM Michal Hocko wrote: > > On Mon 01-03-21 07:10:11, Shakeel Butt wrote: > > On Mon, Mar 1, 2021 at 4:12 AM Michal Hocko wrote: > > > > > > On Fri 26-02-21 16:00:30, Shakeel Butt wrote: > > > > On Fri, Feb 26, 2021 at 3:14 PM Mike Kravetz > > > > wrote: > > > > > > >

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Michal Hocko
On Mon 01-03-21 07:10:11, Shakeel Butt wrote: > On Mon, Mar 1, 2021 at 4:12 AM Michal Hocko wrote: > > > > On Fri 26-02-21 16:00:30, Shakeel Butt wrote: > > > On Fri, Feb 26, 2021 at 3:14 PM Mike Kravetz > > > wrote: > > > > > > > > Cc: Michal > > > > > > > > On 2/26/21 2:44 PM, Shakeel Butt wro

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Shakeel Butt
On Mon, Mar 1, 2021 at 4:12 AM Michal Hocko wrote: > > On Fri 26-02-21 16:00:30, Shakeel Butt wrote: > > On Fri, Feb 26, 2021 at 3:14 PM Mike Kravetz > > wrote: > > > > > > Cc: Michal > > > > > > On 2/26/21 2:44 PM, Shakeel Butt wrote: > > > > On Fri, Feb 26, 2021 at 2:09 PM syzbot > > > > wrot

Re: possible deadlock in sk_clone_lock

2021-03-01 Thread Michal Hocko
On Fri 26-02-21 16:00:30, Shakeel Butt wrote: > On Fri, Feb 26, 2021 at 3:14 PM Mike Kravetz wrote: > > > > Cc: Michal > > > > On 2/26/21 2:44 PM, Shakeel Butt wrote: > > > On Fri, Feb 26, 2021 at 2:09 PM syzbot > > > wrote: > > > > >> other info that might help us debug this: > > >> > > >> Pos

Re: possible deadlock in sk_clone_lock

2021-02-26 Thread Shakeel Butt
On Fri, Feb 26, 2021 at 3:14 PM Mike Kravetz wrote: > > Cc: Michal > > On 2/26/21 2:44 PM, Shakeel Butt wrote: > > On Fri, Feb 26, 2021 at 2:09 PM syzbot > > wrote: > > >> other info that might help us debug this: > >> > >> Possible interrupt unsafe locking scenario: > >> > >>CPU0

Re: possible deadlock in sk_clone_lock

2021-02-26 Thread Mike Kravetz
Cc: Michal On 2/26/21 2:44 PM, Shakeel Butt wrote: > On Fri, Feb 26, 2021 at 2:09 PM syzbot > wrote: >> other info that might help us debug this: >> >> Possible interrupt unsafe locking scenario: >> >>CPU0CPU1 >> >> lock(hugetlb_

Re: possible deadlock in sk_clone_lock

2021-02-26 Thread Shakeel Butt
On Fri, Feb 26, 2021 at 2:09 PM syzbot wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit:577c2835 Add linux-next specific files for 20210224 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=137cef82d0 > kernel config: https:

possible deadlock in sk_clone_lock

2021-02-26 Thread syzbot
Hello, syzbot found the following issue on: HEAD commit:577c2835 Add linux-next specific files for 20210224 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=137cef82d0 kernel config: https://syzkaller.appspot.com/x/.config?x=e9bb3d369b3bf49 dashboard l