Re: INFO: rcu detected stall in corrupted (3)

2019-04-01 Thread Juri Lelli
Hi, On 30/03/19 12:09, Borislav Petkov wrote: > On Sat, Mar 30, 2019 at 07:57:50PM +0900, Tetsuo Handa wrote: > > Yes. But what such threshold be? 0.1 second? 1 second? 10 seconds? > > Can we find a threshold where everyone can agree on? > > This is what we do all day on lkml: discussing changes

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Borislav Petkov
On Sat, Mar 30, 2019 at 11:07:40PM +0900, Tetsuo Handa wrote: > I think that syzbot should for now refrain from testing syscalls that change > scheduling related attributes, And how would we know about problems there, otherwise? -- Regards/Gruss, Boris. Good mailing practices for 400:

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Tetsuo Handa
On 2019/03/30 20:09, Borislav Petkov wrote: > On Sat, Mar 30, 2019 at 07:57:50PM +0900, Tetsuo Handa wrote: >> Yes. But what such threshold be? 0.1 second? 1 second? 10 seconds? >> Can we find a threshold where everyone can agree on? > > This is what we do all day on lkml: discussing changes so

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Borislav Petkov
On Sat, Mar 30, 2019 at 07:57:50PM +0900, Tetsuo Handa wrote: > Yes. But what such threshold be? 0.1 second? 1 second? 10 seconds? > Can we find a threshold where everyone can agree on? This is what we do all day on lkml: discussing changes so that (almost) everyone is happy with them. :-) --

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Tetsuo Handa
On 2019/03/30 19:45, Borislav Petkov wrote: > On Sat, Mar 30, 2019 at 07:40:11PM +0900, Tetsuo Handa wrote: >> But how can the scheduler be aware of various watchdogs' thresholds? > > I think what tglx means is sched_setattr() should be fixed to fail due > to the bogus value. > Yes. But what

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Borislav Petkov
On Sat, Mar 30, 2019 at 07:40:11PM +0900, Tetsuo Handa wrote: > But how can the scheduler be aware of various watchdogs' thresholds? I think what tglx means is sched_setattr() should be fixed to fail due to the bogus value. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Tetsuo Handa
On 2019/03/30 16:46, Thomas Gleixner wrote: > On Sat, 30 Mar 2019, Tetsuo Handa wrote: >> This reproducer does sched_setattr(SCHED_DEADLINE) with bogus value, as with >> a reproducer for "INFO: rcu detected stall in sys_sendfile64" did. >> >> sched_setattr(0, {size=0, sched_policy=0x6 /*

Re: INFO: rcu detected stall in corrupted (3)

2019-03-30 Thread Thomas Gleixner
On Sat, 30 Mar 2019, Tetsuo Handa wrote: > On 2019/03/30 7:34, syzbot wrote: > > Hello, > > > > syzbot found the following crash on: > > > > HEAD commit:    8c2ffd91 Linux 5.1-rc2 > > git tree:   upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=15099d2b20 > >

Re: INFO: rcu detected stall in corrupted (3)

2019-03-29 Thread Tetsuo Handa
On 2019/03/30 7:34, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit:    8c2ffd91 Linux 5.1-rc2 > git tree:   upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=15099d2b20 > kernel config: