Re: kern/38460: fstrans_start code in genfs_do_putpages is racy

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

The following reply was made to PR kern/38460; it has been noted by GNATS.

From: Juergen Hannken-Illjes <hannken%eis.cs.tu-bs.de@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost, 
netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/38460: fstrans_start code in genfs_do_putpages is racy
Date: Sat, 19 Apr 2008 11:45:04 +0200

 On Sat, Apr 19, 2008 at 08:05:00AM +0000, yamt%mwd.biglobe.ne.jp@localhost 
wrote:
 > >Synopsis:       fstrans_start code in genfs_do_putpages is racy
 
 This diff should fix it. Ok?
 
 -- 
 Juergen Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig 
(Germany)
 
 Index: genfs_io.c
 ===================================================================
 RCS file: /cvsroot/src/sys/miscfs/genfs/genfs_io.c,v
 retrieving revision 1.5
 diff -p -u -2 -r1.5 genfs_io.c
 --- genfs_io.c 18 Jan 2008 11:01:23 -0000      1.5
 +++ genfs_io.c 19 Apr 2008 09:38:14 -0000
 @@ -779,7 +779,8 @@ genfs_do_putpages(struct vnode *vp, off_
            vp, uobj->uo_npages, startoff, endoff - startoff);
  
 +      has_trans = false;
 +
  retry:
        modified = false;
 -      has_trans = false;
        flags = origflags;
        KASSERT((vp->v_iflag & VI_ONWORKLST) != 0 ||
 @@ -791,4 +792,6 @@ retry:
                                vn_syncer_remove_from_worklist(vp);
                }
 +              if (has_trans)
 +                      fstrans_done(vp->v_mount);
                mutex_exit(slock);
                return (0);
 @@ -799,5 +802,5 @@ retry:
         */
  
 -      if ((flags & PGO_CLEANIT) != 0) {
 +      if (!has_trans && (flags & PGO_CLEANIT) != 0) {
                mutex_exit(slock);
                if (pagedaemon) {
 @@ -809,4 +812,5 @@ retry:
                has_trans = true;
                mutex_enter(slock);
 +              goto retry;
        }