Author: mjg Date: Wed Sep 4 19:23:18 2019 New Revision: 351825 URL: https://svnweb.freebsd.org/changeset/base/351825
Log: vfs: fully hold vnodes in vnlru_free_locked Currently the code only bumps holdcnt and clears the VI_FREE flag, not performing actual vhold. Since the vnode is still visible elsewhere, a potential new user can find it and incorrectly assume it is properly held. Use vholdl instead to correctly hold the vnode. Another place recycling (vlrureclaim) does this already. Reviewed by: kib Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D21522 Modified: head/sys/kern/vfs_subr.c Modified: head/sys/kern/vfs_subr.c ============================================================================== --- head/sys/kern/vfs_subr.c Wed Sep 4 19:19:23 2019 (r351824) +++ head/sys/kern/vfs_subr.c Wed Sep 4 19:23:18 2019 (r351825) @@ -1102,7 +1102,6 @@ vnlru_free_locked(int count, struct vfsops *mnt_op) ("Removing vnode not on freelist")); KASSERT((vp->v_iflag & VI_ACTIVE) == 0, ("Mangling active vnode")); - TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); /* * Don't recycle if our vnode is from different type @@ -1114,7 +1113,6 @@ vnlru_free_locked(int count, struct vfsops *mnt_op) */ if ((mnt_op != NULL && (mp = vp->v_mount) != NULL && mp->mnt_op != mnt_op) || !VI_TRYLOCK(vp)) { - TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); continue; } VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0, @@ -1129,11 +1127,8 @@ vnlru_free_locked(int count, struct vfsops *mnt_op) * activating. */ freevnodes--; - vp->v_iflag &= ~VI_FREE; - VNODE_REFCOUNT_FENCE_REL(); - refcount_acquire(&vp->v_holdcnt); - mtx_unlock(&vnode_free_list_mtx); + vholdl(vp); VI_UNLOCK(vp); vtryrecycle(vp); /* _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
