Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Wed, Mar 08, 2017 at 07:05:13AM +0800, Boqun Feng wrote: > On Tue, Mar 07, 2017 at 07:27:15AM -0800, Paul E. McKenney wrote: > > On Tue, Mar 07, 2017 at 03:43:42PM +0100, Dmitry Vyukov wrote: > > > On Tue, Mar 7, 2017 at 3:27 PM, Boqun Feng wrote: > > > > On Tue, Mar 07, 2017 at 08:05:19AM +010

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Wed, Mar 08, 2017 at 10:44:17AM +0800, Boqun Feng wrote: > On Tue, Mar 07, 2017 at 06:26:03PM -0800, Paul E. McKenney wrote: > > On Wed, Mar 08, 2017 at 09:39:13AM +0800, Boqun Feng wrote: > > > On Tue, Mar 07, 2017 at 03:31:54PM -0800, Paul E. McKenney wrote: > > > > On Wed, Mar 08, 2017 at 07:

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Boqun Feng
On Tue, Mar 07, 2017 at 06:26:03PM -0800, Paul E. McKenney wrote: > On Wed, Mar 08, 2017 at 09:39:13AM +0800, Boqun Feng wrote: > > On Tue, Mar 07, 2017 at 03:31:54PM -0800, Paul E. McKenney wrote: > > > On Wed, Mar 08, 2017 at 07:05:13AM +0800, Boqun Feng wrote: > > > > On Tue, Mar 07, 2017 at 07:

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Wed, Mar 08, 2017 at 09:39:13AM +0800, Boqun Feng wrote: > On Tue, Mar 07, 2017 at 03:31:54PM -0800, Paul E. McKenney wrote: > > On Wed, Mar 08, 2017 at 07:05:13AM +0800, Boqun Feng wrote: > > > On Tue, Mar 07, 2017 at 07:27:15AM -0800, Paul E. McKenney wrote: > > > > On Tue, Mar 07, 2017 at 03:

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Boqun Feng
On Tue, Mar 07, 2017 at 03:31:54PM -0800, Paul E. McKenney wrote: > On Wed, Mar 08, 2017 at 07:05:13AM +0800, Boqun Feng wrote: > > On Tue, Mar 07, 2017 at 07:27:15AM -0800, Paul E. McKenney wrote: > > > On Tue, Mar 07, 2017 at 03:43:42PM +0100, Dmitry Vyukov wrote: > > > > On Tue, Mar 7, 2017 at 3

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Boqun Feng
On Tue, Mar 07, 2017 at 07:27:15AM -0800, Paul E. McKenney wrote: > On Tue, Mar 07, 2017 at 03:43:42PM +0100, Dmitry Vyukov wrote: > > On Tue, Mar 7, 2017 at 3:27 PM, Boqun Feng wrote: > > > On Tue, Mar 07, 2017 at 08:05:19AM +0100, Dmitry Vyukov wrote: > > > [...] > > >> >> > > >> >> What is that

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Tue, Mar 07, 2017 at 03:43:42PM +0100, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 3:27 PM, Boqun Feng wrote: > > On Tue, Mar 07, 2017 at 08:05:19AM +0100, Dmitry Vyukov wrote: > > [...] > >> >> > >> >> What is that mutex? And what locks/unlocks provide synchronization? I > >> >> see that one

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Tue, Mar 07, 2017 at 08:05:19AM +0100, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 12:08 AM, Paul E. McKenney > wrote: > >> >> >> >> Hello, > >> >> >> >> > >> >> >> >> Paul, you wanted bugs in rcu. > >> >> >> > > >> >> >> > Well, whether I want them or not, I must deal with them. ;-) > >> >>

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Paul E. McKenney
On Tue, Mar 07, 2017 at 07:37:57PM +0100, Dmitry Vyukov wrote: > On Tue, Mar 7, 2017 at 4:27 PM, Paul E. McKenney > wrote: > >> > [...] > >> >> >> > >> >> >> What is that mutex? And what locks/unlocks provide synchronization? I > >> >> >> see that one uses exp_mutex and another -- exp_wake_mutex.

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Dmitry Vyukov
On Tue, Mar 7, 2017 at 4:27 PM, Paul E. McKenney wrote: >> > [...] >> >> >> >> >> >> What is that mutex? And what locks/unlocks provide synchronization? I >> >> >> see that one uses exp_mutex and another -- exp_wake_mutex. >> >> > >> >> > Both of them. >> >> > >> >> > ->exp_mutex is acquired by th

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Dmitry Vyukov
On Tue, Mar 7, 2017 at 3:27 PM, Boqun Feng wrote: > On Tue, Mar 07, 2017 at 08:05:19AM +0100, Dmitry Vyukov wrote: > [...] >> >> >> >> What is that mutex? And what locks/unlocks provide synchronization? I >> >> see that one uses exp_mutex and another -- exp_wake_mutex. >> > >> > Both of them. >> >

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Boqun Feng
On Tue, Mar 07, 2017 at 08:05:19AM +0100, Dmitry Vyukov wrote: [...] > >> > >> What is that mutex? And what locks/unlocks provide synchronization? I > >> see that one uses exp_mutex and another -- exp_wake_mutex. > > > > Both of them. > > > > ->exp_mutex is acquired by the task requesting the grace

Re: rcu: WARNING in rcu_seq_end

2017-03-07 Thread Dmitry Vyukov
On Tue, Mar 7, 2017 at 12:08 AM, Paul E. McKenney wrote: >> >> >> >> Hello, >> >> >> >> >> >> >> >> Paul, you wanted bugs in rcu. >> >> >> > >> >> >> > Well, whether I want them or not, I must deal with them. ;-) >> >> >> > >> >> >> >> I've got this WARNING while running syzkaller fuzzer on >> >>

Re: rcu: WARNING in rcu_seq_end

2017-03-06 Thread Paul E. McKenney
On Mon, Mar 06, 2017 at 11:11:23AM +0100, Dmitry Vyukov wrote: > On Mon, Mar 6, 2017 at 11:07 AM, Paul E. McKenney > wrote: > > On Mon, Mar 06, 2017 at 10:24:24AM +0100, Dmitry Vyukov wrote: > >> On Sun, Mar 5, 2017 at 7:47 PM, Paul E. McKenney > >> wrote: > >> > On Sun, Mar 05, 2017 at 11:50:39A

Re: rcu: WARNING in rcu_seq_end

2017-03-06 Thread Dmitry Vyukov
On Sun, Mar 5, 2017 at 7:47 PM, Paul E. McKenney wrote: > On Sun, Mar 05, 2017 at 11:50:39AM +0100, Dmitry Vyukov wrote: >> On Sat, Mar 4, 2017 at 9:40 PM, Paul E. McKenney >> wrote: >> > On Sat, Mar 04, 2017 at 05:01:19PM +0100, Dmitry Vyukov wrote: >> >> Hello, >> >> >> >> Paul, you wanted bugs

Re: rcu: WARNING in rcu_seq_end

2017-03-06 Thread Dmitry Vyukov
On Mon, Mar 6, 2017 at 11:07 AM, Paul E. McKenney wrote: > On Mon, Mar 06, 2017 at 10:24:24AM +0100, Dmitry Vyukov wrote: >> On Sun, Mar 5, 2017 at 7:47 PM, Paul E. McKenney >> wrote: >> > On Sun, Mar 05, 2017 at 11:50:39AM +0100, Dmitry Vyukov wrote: >> >> On Sat, Mar 4, 2017 at 9:40 PM, Paul E.

Re: rcu: WARNING in rcu_seq_end

2017-03-06 Thread Paul E. McKenney
On Mon, Mar 06, 2017 at 10:24:24AM +0100, Dmitry Vyukov wrote: > On Sun, Mar 5, 2017 at 7:47 PM, Paul E. McKenney > wrote: > > On Sun, Mar 05, 2017 at 11:50:39AM +0100, Dmitry Vyukov wrote: > >> On Sat, Mar 4, 2017 at 9:40 PM, Paul E. McKenney > >> wrote: > >> > On Sat, Mar 04, 2017 at 05:01:19PM

Re: rcu: WARNING in rcu_seq_end

2017-03-05 Thread Paul E. McKenney
On Sun, Mar 05, 2017 at 11:50:39AM +0100, Dmitry Vyukov wrote: > On Sat, Mar 4, 2017 at 9:40 PM, Paul E. McKenney > wrote: > > On Sat, Mar 04, 2017 at 05:01:19PM +0100, Dmitry Vyukov wrote: > >> Hello, > >> > >> Paul, you wanted bugs in rcu. > > > > Well, whether I want them or not, I must deal wi

Re: rcu: WARNING in rcu_seq_end

2017-03-05 Thread Dmitry Vyukov
On Sat, Mar 4, 2017 at 9:40 PM, Paul E. McKenney wrote: > On Sat, Mar 04, 2017 at 05:01:19PM +0100, Dmitry Vyukov wrote: >> Hello, >> >> Paul, you wanted bugs in rcu. > > Well, whether I want them or not, I must deal with them. ;-) > >> I've got this WARNING while running syzkaller fuzzer on >> 8

Re: rcu: WARNING in rcu_seq_end

2017-03-04 Thread Paul E. McKenney
On Sat, Mar 04, 2017 at 05:01:19PM +0100, Dmitry Vyukov wrote: > Hello, > > Paul, you wanted bugs in rcu. Well, whether I want them or not, I must deal with them. ;-) > I've got this WARNING while running syzkaller fuzzer on > 86292b33d4b79ee03e2f43ea0381ef85f077c760: > > [ cut her

rcu: WARNING in rcu_seq_end

2017-03-04 Thread Dmitry Vyukov
Hello, Paul, you wanted bugs in rcu. I've got this WARNING while running syzkaller fuzzer on 86292b33d4b79ee03e2f43ea0381ef85f077c760: [ cut here ] WARNING: CPU: 0 PID: 4832 at kernel/rcu/tree.c:3533 rcu_seq_end+0x110/0x140 kernel/rcu/tree.c:3533 Kernel panic - not syncin