From d72b4d3918f6a51c1da7580a932983e66acc2dff Mon Sep 17 00:00:00 2001 From: Konstantin Belousov Date: Mon, 9 Jan 2017 20:14:18 +0000 Subject: [PATCH] Forcibly remove the cached items from pseudofs vncache on module unload. If some process' nodes were accessed using procfs and the process cannot exit properly at the time modunload event is reported to the pseudofs-backed filesystem, the assertion in pfs_vncache_unload() is triggered. Assertion is correct, the cache should be cleaned. Approved by: des (pseudofs maintainer) Reported and tested by: pho Sponsored by: The FreeBSD Foundation MFC after: 1 week --- sys/fs/pseudofs/pseudofs_vncache.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/sys/fs/pseudofs/pseudofs_vncache.c b/sys/fs/pseudofs/pseudofs_vncache.c index 1bec5a4c885..093d80565ea 100644 --- a/sys/fs/pseudofs/pseudofs_vncache.c +++ b/sys/fs/pseudofs/pseudofs_vncache.c @@ -51,6 +51,7 @@ static struct mtx pfs_vncache_mutex; static struct pfs_vdata *pfs_vncache; static eventhandler_tag pfs_exit_tag; static void pfs_exit(void *arg, struct proc *p); +static void pfs_purge_locked(struct pfs_node *pn, bool force); static SYSCTL_NODE(_vfs_pfs, OID_AUTO, vncache, CTLFLAG_RW, 0, "pseudofs vnode cache"); @@ -97,6 +98,9 @@ pfs_vncache_unload(void) { EVENTHANDLER_DEREGISTER(process_exit, pfs_exit_tag); + mtx_lock(&pfs_vncache_mutex); + pfs_purge_locked(NULL, true); + mtx_unlock(&pfs_vncache_mutex); KASSERT(pfs_vncache_entries == 0, ("%d vncache entries remaining", pfs_vncache_entries)); mtx_destroy(&pfs_vncache_mutex); @@ -272,7 +276,7 @@ pfs_vncache_free(struct vnode *vp) * used to implement the cache. */ static void -pfs_purge_locked(struct pfs_node *pn) +pfs_purge_locked(struct pfs_node *pn, bool force) { struct pfs_vdata *pvd; struct vnode *vnp; @@ -280,7 +284,8 @@ pfs_purge_locked(struct pfs_node *pn) mtx_assert(&pfs_vncache_mutex, MA_OWNED); pvd = pfs_vncache; while (pvd != NULL) { - if (pvd->pvd_dead || (pn != NULL && pvd->pvd_pn == pn)) { + if (force || pvd->pvd_dead || + (pn != NULL && pvd->pvd_pn == pn)) { vnp = pvd->pvd_vnode; vhold(vnp); mtx_unlock(&pfs_vncache_mutex); @@ -301,7 +306,7 @@ pfs_purge(struct pfs_node *pn) { mtx_lock(&pfs_vncache_mutex); - pfs_purge_locked(pn); + pfs_purge_locked(pn, false); mtx_unlock(&pfs_vncache_mutex); } @@ -321,6 +326,6 @@ pfs_exit(void *arg, struct proc *p) if (pvd->pvd_pid == p->p_pid) dead = pvd->pvd_dead = 1; if (dead) - pfs_purge_locked(NULL); + pfs_purge_locked(NULL, false); mtx_unlock(&pfs_vncache_mutex); }