Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-20 Thread Dmitry Vyukov
On Thu, Mar 14, 2019 at 11:52 AM Tetsuo Handa wrote: > > On 2019/03/14 8:40, Eric Biggers wrote: > > On Wed, Mar 13, 2019 at 07:43:38AM +0100, 'Dmitry Vyukov' via > > syzkaller-bugs wrote: > >>> Also, humans can sometimes find more simpler C reproducers from syzbot > >>> provided > >>>

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-20 Thread Dmitry Vyukov
On Thu, Mar 14, 2019 at 11:52 AM Tetsuo Handa wrote: > > On 2019/03/14 8:40, Eric Biggers wrote: > > On Wed, Mar 13, 2019 at 07:43:38AM +0100, 'Dmitry Vyukov' via > > syzkaller-bugs wrote: > >>> Also, humans can sometimes find more simpler C reproducers from syzbot > >>> provided > >>>

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-14 Thread Tetsuo Handa
On 2019/03/14 8:40, Eric Biggers wrote: > On Wed, Mar 13, 2019 at 07:43:38AM +0100, 'Dmitry Vyukov' via syzkaller-bugs > wrote: >>> Also, humans can sometimes find more simpler C reproducers from syzbot >>> provided >>> reproducers. It would be nice if syzbot can accept and use a user defined C

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-13 Thread Eric Biggers
On Wed, Mar 13, 2019 at 07:43:38AM +0100, 'Dmitry Vyukov' via syzkaller-bugs wrote: > > Also, humans can sometimes find more simpler C reproducers from syzbot > > provided > > reproducers. It would be nice if syzbot can accept and use a user defined C > > reproducer for testing. > > It would be

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-13 Thread Dmitry Vyukov
On Wed, Mar 13, 2019 at 5:37 PM Theodore Ts'o wrote: > > On Wed, Mar 13, 2019 at 07:43:38AM +0100, Dmitry Vyukov wrote: > > It would be more useful to accept patches that make syzkaller create > > better reproducers from these people. Manual work is not scalable. We > > would need 10 reproducers

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-13 Thread Theodore Ts'o
On Wed, Mar 13, 2019 at 07:43:38AM +0100, Dmitry Vyukov wrote: > It would be more useful to accept patches that make syzkaller create > better reproducers from these people. Manual work is not scalable. We > would need 10 reproducers per day for a dozen of OSes (incl some > private

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-13 Thread Dmitry Vyukov
On Tue, Mar 12, 2019 at 10:11 PM Tetsuo Handa wrote: > > On 2019/03/13 2:15, Dmitry Vyukov wrote: > >> Also, this bisection is finding multiple different crash patterns, which > >> suggests that the crashed tests are not giving correct feedback to syzbot. > > > > Treating different crashes as

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-12 Thread Tetsuo Handa
On 2019/03/13 2:15, Dmitry Vyukov wrote: >> Also, this bisection is finding multiple different crash patterns, which >> suggests that the crashed tests are not giving correct feedback to syzbot. > > Treating different crashes as just "crash" is intended. Kernel bugs > can manifest in very

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-12 Thread Dmitry Vyukov
On Tue, Mar 12, 2019 at 3:30 PM Tetsuo Handa wrote: > > (Moving most recipients to bcc: in order to avoid flooding.) > > On 2019/03/12 13:08, Al Viro wrote: > > Umm... Might be a good idea to add some plausibility filters - it is, > > in theory, possible that adding a line in a comment changes

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-03-12 Thread Tetsuo Handa
(Moving most recipients to bcc: in order to avoid flooding.) On 2019/03/12 13:08, Al Viro wrote: > Umm... Might be a good idea to add some plausibility filters - it is, > in theory, possible that adding a line in a comment changes behaviour > (without compiler bugs, even - playing with __LINE__

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-01-19 Thread Tetsuo Handa
On 2019/01/19 20:41, Dmitry Vyukov wrote: > On Sat, Jan 19, 2019 at 12:32 PM syzbot > wrote: >> >> Hello, >> >> syzbot found the following crash on: >> >> HEAD commit:2339e91d0e66 Merge tag 'media/v5.0-1' of git://git.kernel... >> git tree: upstream >> console output:

Re: INFO: rcu detected stall in sys_sendfile64 (2)

2019-01-19 Thread Dmitry Vyukov
On Sat, Jan 19, 2019 at 12:32 PM syzbot wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit:2339e91d0e66 Merge tag 'media/v5.0-1' of git://git.kernel... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=175f2638c0 > kernel

INFO: rcu detected stall in sys_sendfile64 (2)

2019-01-19 Thread syzbot
Hello, syzbot found the following crash on: HEAD commit:2339e91d0e66 Merge tag 'media/v5.0-1' of git://git.kernel... git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=175f2638c0 kernel config: https://syzkaller.appspot.com/x/.config?x=abc3dc9b7a900258