On Sat, Jul 14, 2012 at 02:05:10PM +0100, Al Viro wrote: > On Tue, Jul 10, 2012 at 10:18:30PM +0800, wfg@xxxxxxxxxxxxxxx wrote: > > Hi Al, > > > > The linux-next kernel reliably hung after this line: > > > > [ 4.846260] debug: unmapping init [mem 0xffff88000182a000-0xffff8800019fffff] > > > > And it's bisected to commit: > > > > commit 4a9ffe81385c2af04f296bea05482f34e02ea10d > > Author: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > > Date: Sun Jun 24 09:56:45 2012 +0400 > > > > switch fput to task_work_add > > > > ... and schedule_work() for interrupt/kernel_thread callers > > (and yes, now it *is* OK to call from interrupt). > > > > I tried add this debug aid: > > > > init_post(void): > > + printk(KERN_WARNING "flush_delayed_fput\n"); > > flush_delayed_fput(); > > + printk(KERN_WARNING "flush_delayed_fput done\n"); > > > > And then it hangs after "flush_delayed_fput done". So it's not directly > > freezing inside flush_delayed_fput().. > > Could you post a stack trace, etc.? I'll try to reproduce that one, obviously, > but... Yeah, I'm wondering (and will try) if it will help sending SYSRQ into kvm guest. It's rather clueless without a back trace.. Thanks, Fengguang -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
