git: 8db7d16526de - main - geom_vfs: lock devvp in g_vfs_close()

From: Konstantin Belousov <kib_at_FreeBSD.org>
Date: Fri, 12 Nov 2021 23:04:13 UTC
The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=8db7d16526debbca6bc7a32a57fd0378e48e37de

commit 8db7d16526debbca6bc7a32a57fd0378e48e37de
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2021-11-01 05:46:52 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2021-11-12 23:00:13 +0000

    geom_vfs: lock devvp in g_vfs_close()
    
    It is needed for g_vfs_close() invalidating the buffers.  We rely on the
    vnode lock for correctness.
    
    Reported and tested by: pho
    Reviewed by:    markj
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D32761
---
 sys/geom/geom_vfs.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sys/geom/geom_vfs.c b/sys/geom/geom_vfs.c
index 592062b8b12a..9590fee11000 100644
--- a/sys/geom/geom_vfs.c
+++ b/sys/geom/geom_vfs.c
@@ -302,12 +302,16 @@ g_vfs_close(struct g_consumer *cp)
 {
 	struct g_geom *gp;
 	struct g_vfs_softc *sc;
+	struct vnode *vp;
 
 	g_topology_assert();
 
 	gp = cp->geom;
 	sc = gp->softc;
+	vp = cp->private;
+	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 	bufobj_invalbuf(sc->sc_bo, V_SAVE, 0, 0);
+	VOP_UNLOCK(vp);
 	sc->sc_bo->bo_private = cp->private;
 	gp->softc = NULL;
 	mtx_destroy(&sc->sc_mtx);