>Number: 161887 >Category: kern >Synopsis: panic at vm_page_wire with FreeBSD 9.0 Beta 3 >Confidential: no >Severity: serious >Priority: high >Responsible: freebsd-bugs >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Fri Oct 21 18:10:10 UTC 2011 >Closed-Date: >Last-Modified: >Originator: Penta Upa >Release: FreeBSD 9.0 Beta 3 >Organization: >Environment: FreeBSD scache 9.0-BETA3 FreeBSD 9.0-BETA3 #0: Sat Sep 24 21:31:28 UTC 2011 r...@farrell.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64
>Description: External modules calling vm_page_wire() even after calling vm_page_lock() results in the following assertion failure in vm_page.c panic: mutex page lock not owned at /usr/src/sys/vm/vm_page:1845 Interestingly check for vm page locked is also done in the external module but there is no assertion there. More clearly within the external module vm_page_lock(pp); vm_page_lock_assert(pp, MA_OWNED); /* No panic here */ vm_page_wire(pp); /* Panic here for the same assertion as above, strange */ vm_page_unlock(pp); The machine in use is a fresh install of FreeBSD 9 Beta 3. No changes to the kernel were made. Problem however exists ever after a kernel recompile. I have also sent a mail to the mailing list on this. http://lists.freebsd.org/pipermail/freebsd-current/2011-October/028550.html I dont have a backtrace of the crash as i'm unable to configure kernel dumps yet. Will post them once i have it. >How-To-Repeat: Try the attached vmtest.c Makefile contents are KMOD = vmtest SRCS = vmtest.c .include <bsd.kmod.mk> >Fix: Patch attached with submission follows: #include <sys/param.h> #include <sys/module.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/types.h> #include <sys/param.h> #include <sys/time.h> #include <sys/systm.h> #include <sys/lock.h> #include <sys/mutex.h> #include <vm/vm.h> #include <vm/vm_extern.h> #include <vm/vm_param.h> #include <vm/pmap.h> #include <vm/vm_map.h> #include <vm/vm_page.h> #include <vm/vm_object.h> static void vmtest(void) { vm_page_t pp; pp = vm_page_alloc(NULL, 0, VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL); if (!pp) { printf("Page allocation failure\n"); return; } vm_page_lock(pp); vm_page_lock_assert(pp, MA_OWNED); vm_page_wire(pp); vm_page_unlock(pp); } /* The function called at load/unload. */ static int event_handler(struct module *module, int event, void *arg) { switch (event) { case MOD_LOAD: vmtest(); break; case MOD_UNLOAD: break; default: break; } return 0; } static moduledata_t vmtest_conf = { "vmtest", event_handler, NULL }; DECLARE_MODULE(vmtest, vmtest_conf, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); >Release-Note: >Audit-Trail: >Unformatted: _______________________________________________ freebsd-bugs@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-bugs To unsubscribe, send any mail to "freebsd-bugs-unsubscr...@freebsd.org"
