Possible kqueue related issue on STABLE/RC.

[Patrick Lamaiziere]

Le Fri, 20 Sep 2013 15:17:05 +0200,
Patrick Lamaiziere <patfbsd at davenulle.org> a écrit :

> Le Thu, 12 Sep 2013 10:36:43 +0300,
> Konstantin Belousov <kostikbel at gmail.com> a écrit :
> 
> Hello,
> 
> > Might be, your issue is that some filesystems do not care about
> > proper locking mode for the fifos.  UFS carefully disables shared
> > locking for VFIFO, but it seems ZFS is not.  I can propose the
> > following band-aid, which could help you.
> > 
> > I have no idea is it the same issue as the kqueue panic.
> > 
> > diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
> > index c53030a..00bd998 100644
> > --- a/sys/kern/vfs_vnops.c
> > +++ b/sys/kern/vfs_vnops.c
> > @@ -267,6 +267,8 @@ vn_open_vnode(struct vnode *vp, int fmode,
> > struct ucred *cred, return (error);
> >  		}
> >  	}
> > +	if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) !=
> > LK_EXCLUSIVE)
> > +		vn_lock(vp, LK_UPGRADE | LK_RETRY);
> >  	if ((error = VOP_OPEN(vp, fmode, cred, td, fp)) != 0)
> >  		return (error);
> >  
> > @@ -358,7 +360,7 @@ vn_close(vp, flags, file_cred, td)
> >  	struct mount *mp;
> >  	int error, lock_flags;
> >  
> > -	if (!(flags & FWRITE) && vp->v_mount != NULL &&
> > +	if (vp->v_type != VFIFO && !(flags & FWRITE) &&
> > vp->v_mount != NULL && vp->v_mount->mnt_kern_flag &
> > MNTK_EXTENDED_SHARED) lock_flags = LK_SHARED;
> >  	else
> 

Ok This has been mfced to 9.2-STABLE. But I still see this panic with
9-2/STABLE of today (Revision : 255811). This may be better because
before the box paniced within minutes and now within hours (still using poudriere).

panic:
fault code              = supervisor read data, page not present
instruction pointer     = 0x20:0xffffffff808ebfcd
stack pointer           = 0x28:0xffffff824c2e0630
frame pointer           = 0x28:0xffffff824c2e06a0
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 54243 (gvfsd-trash)
trap number             = 12
panic: page fault
cpuid = 2
KDB: stack backtrace:
#0 0xffffffff80939ad6 at kdb_backtrace+0x66
#1 0xffffffff808ffacd at panic+0x1cd
#2 0xffffffff80cdfbe9 at trap_fatal+0x289
#3 0xffffffff80cdff4f at trap_pfault+0x20f
#4 0xffffffff80ce0504 at trap+0x344
#5 0xffffffff80cc9b43 at calltrap+0x8
#6 0xffffffff8099d043 at filt_vfsvnode+0xf3
#7 0xffffffff808c4793 at kqueue_register+0x3e3
#8 0xffffffff808c4de8 at kern_kevent+0x108
#9 0xffffffff808c5950 at sys_kevent+0x90
#10 0xffffffff80cdf3a8 at amd64_syscall+0x5d8
#11 0xffffffff80cc9e27 at Xfast_syscall+0xf7

Full core.txt : 
http://user.lamaiziere.net/patrick/public/vfs_vnode-core.txt.0

Thanks, regards.