Re: kern/53624 (dom0 freeze on domU exit) is still there

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

The following reply was made to PR kern/53624; it has been noted by GNATS.

From: "J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/53624 (dom0 freeze on domU exit) is still there
Date: Fri, 4 Oct 2019 11:40:54 +0200

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 Looks like we have to use fstrans_start_lazy() for VOP_STRATEGY() too
 as it usually calls itself on the file system holding "/dev".
 
 The attached diff could help, please give it a try.
 
 --
 J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig (Germany)
 
 
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 diff -r b9b26f2b5eeb -r 45acdd7da973 sys/kern/vnode_if.c
 --- sys/kern/vnode_if.c
 +++ sys/kern/vnode_if.c
 @@ -49,7 +49,7 @@
  #include <sys/lock.h>
  #include <sys/fstrans.h>
  
 -enum fst_op { FST_NO, FST_YES, FST_TRY };
 +enum fst_op { FST_NO, FST_YES, FST_LAZY, FST_TRY };
  
  static inline int
  vop_pre(vnode_t *vp, struct mount **mp, bool *mpsafe, enum fst_op op)
 @@ -62,7 +62,7 @@ vop_pre(vnode_t *vp, struct mount **mp, 
  		KERNEL_LOCK(1, curlwp);
  	}
  
 -	if (op == FST_YES || op == FST_TRY) {
 +	if (op == FST_YES || op == FST_LAZY || op == FST_TRY) {
  		for (;;) {
  			*mp = vp->v_mount;
  			if (op == FST_TRY) {
 @@ -73,6 +73,8 @@ vop_pre(vnode_t *vp, struct mount **mp, 
  					}
  					return error;
  				}
 +			} else if (op == FST_LAZY) {
 +				fstrans_start_lazy(*mp);
  			} else {
  				fstrans_start(*mp);
  			}
 @@ -91,7 +93,7 @@ static inline void
  vop_post(vnode_t *vp, struct mount *mp, bool mpsafe, enum fst_op op)
  {
  
 -	if (op == FST_YES) {
 +	if (op == FST_YES || op == FST_LAZY) {
  		fstrans_done(mp);
  	}
  
 @@ -1378,11 +1380,11 @@ VOP_STRATEGY(struct vnode *vp,
  	a.a_desc = VDESC(vop_strategy);
  	a.a_vp = vp;
  	a.a_bp = bp;
 -	error = vop_pre(vp, &mp, &mpsafe, FST_YES);
 +	error = vop_pre(vp, &mp, &mpsafe, FST_LAZY);
  	if (error)
  		return error;
  	error = (VCALL(vp, VOFFSET(vop_strategy), &a));
 -	vop_post(vp, mp, mpsafe, FST_YES);
 +	vop_post(vp, mp, mpsafe, FST_LAZY);
  	return error;
  }
  
 
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