Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-21 Thread Paul E. McKenney
On Mon, Sep 21, 2015 at 09:30:49PM +0200, Frederic Weisbecker wrote: > On Fri, Sep 11, 2015 at 10:19:47AM +0800, Boqun Feng wrote: > > Subject: [PATCH 01/27] rcu: Don't disable preemption for Tiny and Tree RCU > > readers > > > > Because preempt_disable() maps to barrier() for non-debug builds, >

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-21 Thread Frederic Weisbecker
On Fri, Sep 11, 2015 at 10:19:47AM +0800, Boqun Feng wrote: > Subject: [PATCH 01/27] rcu: Don't disable preemption for Tiny and Tree RCU > readers > > Because preempt_disable() maps to barrier() for non-debug builds, > it forces the compiler to spill and reload registers. Because Tree > RCU and

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-11 Thread Boqun Feng
On Fri, Sep 11, 2015 at 02:59:37PM -0700, Paul E. McKenney wrote: > > Queued for v4.4, thank you! Please see below for updated commit log, > and please let me know if there are any problems with it. > Looks great to me! Thank you ;-) Regards, Boqun > --

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-11 Thread Paul E. McKenney
> Hi Paul > > On Thu, Sep 10, 2015 at 10:16:49AM -0700, Paul E. McKenney wrote: > > On Thu, Sep 10, 2015 at 06:25:13PM +0800, Boqun Feng wrote: > [snip] > > > > > > Code here is: > > > > > > #ifdef CONFIG_TINY_RCU > > > # ifdef CONFIG_PREEMPT_COUNT > > > VM_BUG_ON(!in_atomic()); <-- BUG trigge

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-10 Thread Boqun Feng
Hi Paul On Thu, Sep 10, 2015 at 10:16:49AM -0700, Paul E. McKenney wrote: > On Thu, Sep 10, 2015 at 06:25:13PM +0800, Boqun Feng wrote: [snip] > > > > Code here is: > > > > #ifdef CONFIG_TINY_RCU > > # ifdef CONFIG_PREEMPT_COUNT > > VM_BUG_ON(!in_atomic()); <-- BUG triggered here. > > # endi

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-10 Thread Paul E. McKenney
On Thu, Sep 10, 2015 at 06:25:13PM +0800, Boqun Feng wrote: > Hi Fengguang, > > On Thu, Sep 10, 2015 at 08:57:08AM +0800, Fengguang Wu wrote: > > Greetings, > > > > 0day kernel testing robot got the below dmesg and the first bad commit is > > > > https://git.kernel.org/pub/scm/linux/kernel/git/p

Re: [rcu] kernel BUG at include/linux/pagemap.h:149!

2015-09-10 Thread Boqun Feng
Hi Fengguang, On Thu, Sep 10, 2015 at 08:57:08AM +0800, Fengguang Wu wrote: > Greetings, > > 0day kernel testing robot got the below dmesg and the first bad commit is > > https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git > dev.2015.09.01a > > commit d0a795e7964cca98fbefefef