From owner-freebsd-stable@FreeBSD.ORG Thu Jul 25 10:00:47 2013 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 469803EA for ; Thu, 25 Jul 2013 10:00:47 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 986052D08 for ; Thu, 25 Jul 2013 10:00:46 +0000 (UTC) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.14.7/8.14.7) with ESMTP id r6PA0bfg083931; Thu, 25 Jul 2013 13:00:37 +0300 (EEST) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.8.3 kib.kiev.ua r6PA0bfg083931 Received: (from kostik@localhost) by tom.home (8.14.7/8.14.7/Submit) id r6PA0bTB083929; Thu, 25 Jul 2013 13:00:37 +0300 (EEST) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 25 Jul 2013 13:00:37 +0300 From: Konstantin Belousov To: Dominic Fandrey Subject: Re: stopping amd causes a freeze Message-ID: <20130725100037.GM5991@kib.kiev.ua> References: <51ED0060.2050502@bsdforen.de> <20130722100720.GI5991@kib.kiev.ua> <51F0DA4B.3000809@bsdforen.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="o0dA3wbhdegQN8Av" Content-Disposition: inline In-Reply-To: <51F0DA4B.3000809@bsdforen.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on tom.home Cc: freebsd-stable@freebsd.org X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Jul 2013 10:00:47 -0000 --o0dA3wbhdegQN8Av Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jul 25, 2013 at 09:56:59AM +0200, Dominic Fandrey wrote: > On 22/07/2013 12:07, Konstantin Belousov wrote: > > On Mon, Jul 22, 2013 at 11:50:24AM +0200, Dominic Fandrey wrote: > >> ... > >> > >> I run amd through sysutils/automounter, which is a scripting solution > >> that generates an amd.map file based on encountered devices and devd > >> events. The SIGHUP it sends to amd to tell it the map file was updated > >> does not cause problems, only a -SIGKILL- SIGTERM may cause the freeze. > >> > >> Nothing was mounted (by amd) during the last freeze. > >> > >> ... > >=20 > > Are you sure that the machine did not paniced ? Do you have serial con= sole ? > >=20 > > The amd(8) locks itself into memory, most likely due to the fear of > > deadlock. There are some known issues with user wirings in stable/9. > > If the problem you see is indeed due to wiring, you might try to apply > > r253187-r253191. >=20 > I tried that. Applying the diff was straightforward enough. But the > resulting kernel paniced as soon as it tried to mount the root fs. You did provided a useful info to diagnose the issue. Patch should keep KBI compatible, but, just in case, if you have any third-party module, rebuild it. >=20 > So I'll wait for the MFC from someone who knows what he/she is doing. Patch below booted for me, and I run some sanity check tests for the mlockall(2), which also did not resulted in misbehaviour. Index: kern/vfs_bio.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- kern/vfs_bio.c (revision 253643) +++ kern/vfs_bio.c (working copy) @@ -1614,7 +1614,8 @@ brelse(struct buf *bp) (PAGE_SIZE - poffset) : resid; =20 KASSERT(presid >=3D 0, ("brelse: extra page")); - vm_page_set_invalid(m, poffset, presid); + if (pmap_page_wired_mappings(m) =3D=3D 0) + vm_page_set_invalid(m, poffset, presid); if (had_bogus) printf("avoided corruption bug in bogus_page/brelse code\n"); } Index: vm/vm_fault.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_fault.c (revision 253643) +++ vm/vm_fault.c (working copy) @@ -286,6 +286,19 @@ RetryFault:; (u_long)vaddr); } =20 + if (fs.entry->eflags & MAP_ENTRY_IN_TRANSITION && + fs.entry->wiring_thread !=3D curthread) { + vm_map_unlock_read(fs.map); + vm_map_lock(fs.map); + if (vm_map_lookup_entry(fs.map, vaddr, &fs.entry) && + (fs.entry->eflags & MAP_ENTRY_IN_TRANSITION)) { + fs.entry->eflags |=3D MAP_ENTRY_NEEDS_WAKEUP; + vm_map_unlock_and_wait(fs.map, 0); + } else + vm_map_unlock(fs.map); + goto RetryFault; + } + /* * Make a reference to this object to prevent its disposal while we * are messing with it. Once we have the reference, the map is free Index: vm/vm_map.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_map.c (revision 253643) +++ vm/vm_map.c (working copy) @@ -2272,6 +2272,7 @@ vm_map_unwire(vm_map_t map, vm_offset_t start, vm_ * above.) */ entry->eflags |=3D MAP_ENTRY_IN_TRANSITION; + entry->wiring_thread =3D curthread; /* * Check the map for holes in the specified region. * If VM_MAP_WIRE_HOLESOK was specified, skip this check. @@ -2304,8 +2305,24 @@ done: else KASSERT(result, ("vm_map_unwire: lookup failed")); } - entry =3D first_entry; - while (entry !=3D &map->header && entry->start < end) { + for (entry =3D first_entry; entry !=3D &map->header && entry->start < end; + entry =3D entry->next) { + /* + * If VM_MAP_WIRE_HOLESOK was specified, an empty + * space in the unwired region could have been mapped + * while the map lock was dropped for draining + * MAP_ENTRY_IN_TRANSITION. Moreover, another thread + * could be simultaneously wiring this new mapping + * entry. Detect these cases and skip any entries + * marked as in transition by us. + */ + if ((entry->eflags & MAP_ENTRY_IN_TRANSITION) =3D=3D 0 || + entry->wiring_thread !=3D curthread) { + KASSERT((flags & VM_MAP_WIRE_HOLESOK) !=3D 0, + ("vm_map_unwire: !HOLESOK and new/changed entry")); + continue; + } + if (rv =3D=3D KERN_SUCCESS && (!user_unwire || (entry->eflags & MAP_ENTRY_USER_WIRED))) { if (user_unwire) @@ -2321,15 +2338,15 @@ done: entry->object.vm_object->type =3D=3D OBJT_SG)); } } - KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, - ("vm_map_unwire: in-transition flag missing")); + KASSERT((entry->eflags & MAP_ENTRY_IN_TRANSITION) !=3D 0, + ("vm_map_unwire: in-transition flag missing")); entry->eflags &=3D ~MAP_ENTRY_IN_TRANSITION; + entry->wiring_thread =3D NULL; if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { entry->eflags &=3D ~MAP_ENTRY_NEEDS_WAKEUP; need_wakeup =3D TRUE; } vm_map_simplify_entry(map, entry); - entry =3D entry->next; } vm_map_unlock(map); if (need_wakeup) @@ -2423,6 +2440,7 @@ vm_map_wire(vm_map_t map, vm_offset_t start, vm_of * above.) */ entry->eflags |=3D MAP_ENTRY_IN_TRANSITION; + entry->wiring_thread =3D curthread; if ((entry->protection & (VM_PROT_READ | VM_PROT_EXECUTE)) =3D=3D 0 || (entry->protection & prot) !=3D prot) { entry->eflags |=3D MAP_ENTRY_WIRE_SKIPPED; @@ -2514,10 +2532,27 @@ done: else KASSERT(result, ("vm_map_wire: lookup failed")); } - entry =3D first_entry; - while (entry !=3D &map->header && entry->start < end) { + for (entry =3D first_entry; entry !=3D &map->header && entry->start < end; + entry =3D entry->next) { if ((entry->eflags & MAP_ENTRY_WIRE_SKIPPED) !=3D 0) goto next_entry_done; + + /* + * If VM_MAP_WIRE_HOLESOK was specified, an empty + * space in the unwired region could have been mapped + * while the map lock was dropped for faulting in the + * pages or draining MAP_ENTRY_IN_TRANSITION. + * Moreover, another thread could be simultaneously + * wiring this new mapping entry. Detect these cases + * and skip any entries marked as in transition by us. + */ + if ((entry->eflags & MAP_ENTRY_IN_TRANSITION) =3D=3D 0 || + entry->wiring_thread !=3D curthread) { + KASSERT((flags & VM_MAP_WIRE_HOLESOK) !=3D 0, + ("vm_map_wire: !HOLESOK and new/changed entry")); + continue; + } + if (rv =3D=3D KERN_SUCCESS) { if (user_wire) entry->eflags |=3D MAP_ENTRY_USER_WIRED; @@ -2542,15 +2577,18 @@ done: } } next_entry_done: - KASSERT(entry->eflags & MAP_ENTRY_IN_TRANSITION, - ("vm_map_wire: in-transition flag missing")); - entry->eflags &=3D ~(MAP_ENTRY_IN_TRANSITION|MAP_ENTRY_WIRE_SKIPPED); + KASSERT((entry->eflags & MAP_ENTRY_IN_TRANSITION) !=3D 0, + ("vm_map_wire: in-transition flag missing %p", entry)); + KASSERT(entry->wiring_thread =3D=3D curthread, + ("vm_map_wire: alien wire %p", entry)); + entry->eflags &=3D ~(MAP_ENTRY_IN_TRANSITION | + MAP_ENTRY_WIRE_SKIPPED); + entry->wiring_thread =3D NULL; if (entry->eflags & MAP_ENTRY_NEEDS_WAKEUP) { entry->eflags &=3D ~MAP_ENTRY_NEEDS_WAKEUP; need_wakeup =3D TRUE; } vm_map_simplify_entry(map, entry); - entry =3D entry->next; } vm_map_unlock(map); if (need_wakeup) @@ -3185,6 +3223,7 @@ vmspace_fork(struct vmspace *vm1, vm_ooffset_t *fo *new_entry =3D *old_entry; new_entry->eflags &=3D ~(MAP_ENTRY_USER_WIRED | MAP_ENTRY_IN_TRANSITION); + new_entry->wiring_thread =3D NULL; new_entry->wired_count =3D 0; if (new_entry->eflags & MAP_ENTRY_VN_WRITECNT) { vnode_pager_update_writecount(object, @@ -3219,6 +3258,7 @@ vmspace_fork(struct vmspace *vm1, vm_ooffset_t *fo */ new_entry->eflags &=3D ~(MAP_ENTRY_USER_WIRED | MAP_ENTRY_IN_TRANSITION | MAP_ENTRY_VN_WRITECNT); + new_entry->wiring_thread =3D NULL; new_entry->wired_count =3D 0; new_entry->object.vm_object =3D NULL; new_entry->cred =3D NULL; Index: vm/vm_map.h =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_map.h (revision 253643) +++ vm/vm_map.h (working copy) @@ -116,6 +116,7 @@ struct vm_map_entry { int wired_count; /* can be paged if =3D 0 */ vm_pindex_t next_read; /* index of the next sequential read */ struct ucred *cred; /* tmp storage for creator ref */ + struct thread *wiring_thread; }; =20 #define MAP_ENTRY_NOSYNC 0x0001 Index: vm/vm_object.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_object.c (revision 253643) +++ vm/vm_object.c (working copy) @@ -1033,9 +1033,9 @@ vm_object_sync(vm_object_t object, vm_ooffset_t of */ flags =3D OBJPR_NOTMAPPED; else if (old_msync) - flags =3D 0; + flags =3D OBJPR_NOTWIRED; else - flags =3D OBJPR_CLEANONLY; + flags =3D OBJPR_CLEANONLY | OBJPR_NOTWIRED; vm_object_page_remove(object, OFF_TO_IDX(offset), OFF_TO_IDX(offset + size + PAGE_MASK), flags); } @@ -1866,7 +1866,8 @@ again: vm_page_lock(p); if ((wirings =3D p->wire_count) !=3D 0 && (wirings =3D pmap_page_wired_mappings(p)) !=3D p->wire_count) { - if ((options & OBJPR_NOTMAPPED) =3D=3D 0) { + if ((options & (OBJPR_NOTWIRED | OBJPR_NOTMAPPED)) =3D=3D + 0) { pmap_remove_all(p); /* Account for removal of wired mappings. */ if (wirings !=3D 0) @@ -1876,8 +1877,7 @@ again: p->valid =3D 0; vm_page_undirty(p); } - vm_page_unlock(p); - continue; + goto next; } if (vm_page_sleep_if_busy(p, TRUE, "vmopar")) goto again; @@ -1886,12 +1886,12 @@ again: if ((options & OBJPR_CLEANONLY) !=3D 0 && p->valid !=3D 0) { if ((options & OBJPR_NOTMAPPED) =3D=3D 0) pmap_remove_write(p); - if (p->dirty) { - vm_page_unlock(p); - continue; - } + if (p->dirty) + goto next; } if ((options & OBJPR_NOTMAPPED) =3D=3D 0) { + if ((options & OBJPR_NOTWIRED) !=3D 0 && wirings !=3D 0) + goto next; pmap_remove_all(p); /* Account for removal of wired mappings. */ if (wirings !=3D 0) { @@ -1903,6 +1903,7 @@ again: } } vm_page_free(p); +next: vm_page_unlock(p); } vm_object_pip_wakeup(object); Index: vm/vm_object.h =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_object.h (revision 253643) +++ vm/vm_object.h (working copy) @@ -176,6 +176,7 @@ struct vm_object { */ #define OBJPR_CLEANONLY 0x1 /* Don't remove dirty pages. */ #define OBJPR_NOTMAPPED 0x2 /* Don't unmap pages. */ +#define OBJPR_NOTWIRED 0x4 /* Don't remove wired pages. */ =20 TAILQ_HEAD(object_q, vm_object); =20 Index: vm/vm_page.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- vm/vm_page.c (revision 253643) +++ vm/vm_page.c (working copy) @@ -2639,8 +2639,6 @@ vm_page_set_invalid(vm_page_t m, int base, int siz vm_page_bits_t bits; =20 VM_OBJECT_LOCK_ASSERT(m->object, MA_OWNED); - KASSERT((m->oflags & VPO_BUSY) =3D=3D 0, - ("vm_page_set_invalid: page %p is busy", m)); bits =3D vm_page_bits(base, size); if (m->valid =3D=3D VM_PAGE_BITS_ALL && bits !=3D 0) pmap_remove_all(m); Index: . =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- . (revision 253643) +++ . (working copy) Property changes on: . ___________________________________________________________________ Modified: svn:mergeinfo Merged /head/sys:r253187-253191 --o0dA3wbhdegQN8Av Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (FreeBSD) iQIcBAEBAgAGBQJR8PdEAAoJEJDCuSvBvK1B1HkP/00UJGRIcAGjHQNJehkq9bSQ DI0KClTl+1Jz2OkoObz2DeVIKlX0v3wKZYIhvKdHIxjUx3YbttqXr5a7MACQbPWZ NFN0OoiNB9rSNxQogZzxWOKVeepegyTOaXmT5k1B+Swv8zdxVwKnbb4AHoD9+7B1 5uOqpCTruYvLGTHqab4/xIMkvvw4bzcWBiXfX3+dXFQIgtf+yVs9iCmhkKyPyotf l/hmXuFWvCe8Mq+7RiCWbbeXjYlGN7wt9Vl5thTVQDYrX04/8deae5jeOuRWWRtF j6oYSqI9o4xojFclZLGSJG/kbEDTBOLEAXjjNSn5OLm3/PSUu/uRpdWqsEZzPkCt wJRI5nlylCKLbnQN8gUqYojnr8IOu/PcHtWYtvB0n7/aeGxeZNkSL93+148CS5YB fBVRZ86goo95r9XcafN3wRmh60555sisshtniLExtE6b39mfNY3ckf7FCOCn/KKb sThwGT/svinjO2HED4aGQZ0XYT6aTucV6TR+TLFgAetIXgcNa/DVWiDjEFWs+8BJ R+aq3zgAVdyEwPhzew9+Zn8yh1n7D7sZ6uihq4DbjwokwJiVxRPAeVKqJkeECvFj Y2EUPjfF+IAHjZyENMC8R3bD8RwJoKxnG1dEflQ3OsgBieglEaYOFbW4uBpPsyQi z6qywP+JCtVyAiYsxQnM =sxJQ -----END PGP SIGNATURE----- --o0dA3wbhdegQN8Av--