Re: "filesystem goof: vop_panic[vop_revoke]" panic

On Mon, Jun 29, 2009 at 11:15:06AM +0100, Lawrence Stewart wrote:
> Hi All,
> 
> My laptop panicked whilst shutting down yesterday. The shutdown sequence 
> seemed to terminate kde4/X correctly but got wedged prior to completing 
> the rest as seen on the console. Details below...
> 
> uname -a:
> FreeBSD lstewart-laptop 8.0-CURRENT FreeBSD 8.0-CURRENT #35 r195046: Fri 
> Jun 26 12:28:02 BST 2009 
> lstewart_at_lstewart-laptop:/usr/obj/usr/src/sys/LAPTOP  amd64
> 
> 
> 
> Backtrace:
> 
>     at /usr/src/sys/kern/subr_kdb.c:534
> #6  0xffffffff8084cb11 in trap (frame=0xffffff8058eb76a0) at 
> /usr/src/sys/amd64/amd64/trap.c:613
> 
> #7  0xffffffff80832f33 in calltrap () at 
> /usr/src/sys/amd64/amd64/exception.S:223
> 
> #8  0xffffffff805a736d in kdb_enter (why=0xffffffff80943489 "panic",
>     msg=0xa <Address 0xa out of bounds>) at cpufunc.h:63
> 
> #9  0xffffffff8057791b in panic (fmt=Variable "fmt" is not available.
> ) at /usr/src/sys/kern/kern_shutdown.c:558
> 
> #10 0xffffffff805f6108 in vop_panic (ap=Variable "ap" is not available.
> ) at /usr/src/sys/kern/vfs_default.c:175
> 
> #11 0xffffffff8054dee7 in exit1 (td=0xffffff00049c9720, rv=1) at 
> vnode_if.h:523
> 
> #12 0xffffffff8057927f in sigexit (td=0xffffff00049c9720, sig=0)
>     at /usr/src/sys/kern/kern_sig.c:2726
> 
> #13 0xffffffff80579e7f in postsig (sig=1491826128) at 
> /usr/src/sys/kern/kern_sig.c:2617
> 
> #14 0xffffffff805b422c in ast (framep=0xffffff8058eb7c90) at 
> /usr/src/sys/kern/subr_trap.c:225
> 
> #15 0xffffffff80833de9 in doreti_ast () at 
> /usr/src/sys/amd64/amd64/exception.S:623
> 

Are you able to reproduce the issue ?
Please try the patch.

diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index ae060da..c00b4f4 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
_at__at_ -334,10 +334,11 _at__at_ exit1(struct thread *td, int rv)
 			tty_unlock(tp);
 		}
 
-		if (ttyvp != NULL && ttyvp->v_type != VBAD) {
+		if (ttyvp != NULL) {
 			sx_xunlock(&proctree_lock);
-			VOP_LOCK(ttyvp, LK_EXCLUSIVE);
-			VOP_REVOKE(ttyvp, REVOKEALL);
+			vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY);
+			if (ttyvp->v_type != VBAD)
+				VOP_REVOKE(ttyvp, REVOKEALL);
 			VOP_UNLOCK(ttyvp, 0);
 			sx_xlock(&proctree_lock);
 		}