From owner-freebsd-current Sat Nov 15 06:44:41 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id GAA06945 for current-outgoing; Sat, 15 Nov 1997 06:44:41 -0800 (PST) (envelope-from owner-freebsd-current) Received: from post.mail.demon.net (post-20.mail.demon.net [194.217.242.27]) by hub.freebsd.org (8.8.7/8.8.7) with SMTP id GAA06934 for ; Sat, 15 Nov 1997 06:44:30 -0800 (PST) (envelope-from fcurrent@jraynard.demon.co.uk) Received: from jraynard.demon.co.uk ([158.152.42.77]) by post.mail.demon.net id aa2003173; 15 Nov 97 14:40 GMT Received: (from fcurrent@localhost) by jraynard.demon.co.uk (8.8.7/8.8.7) id OAA00500; Sat, 15 Nov 1997 14:39:22 GMT (envelope-from fcurrent) Message-ID: <19971115143921.07053@jraynard.demon.co.uk> Date: Sat, 15 Nov 1997 14:39:21 +0000 From: James Raynard To: freebsd-current@freebsd.org Subject: Page fault while in kernel mode Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.81e Sender: owner-freebsd-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk I can replicate this by doing the following: 1. Log on as root on ttyv0 and compile a kernel. 2. Log on my myself on ttyv1, do su and mount a CD-ROM. 3. Navigate around the CD using tcsh's filename completion. 4. System freezes up. DDB says: Fatal trap 12: page fault while in kernel mode fault virtual address = 0x8 fault code = supervisor page read, page not present instruction pointer = 0x8: 0xf3f57dc8 stack pointer = 0x10: 0xf3c98bdc frame pointer = 0x10: 0xf3c98c10 code segment = base 0x0, limit 0xfffff, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor flags = interrupt enabled, resume, IOPL = 0 current process = 890 (tcsh) and gdb -k says: [GDB banner] IdlePTD 219000 current pcb at 1cc844 panic: from debugger #0 boot (howto=256) at ../../kern/kern_shutdown.c:285 285 dumppcb.pcb_cr3 = rcr3(); (kgdb) where #0 boot (howto=256) at ../../kern/kern_shutdown.c:285 #1 0xf011214f in panic (fmt=0xf01013c9 "from debugger") at ../../kern/kern_shutdown.c:415 #2 0xf01013e5 in db_panic (dummy1=-202084920, dummy2=0, dummy3=-1, dummy4=0xf3c92a60 "") at ../../ddb/db_command.c:440 #3 0xf01012d5 in db_command (last_cmdp=0xf01bbac4, cmd_table=0xf01bb914, aux_cmd_tablep=0xf01df234) at ../../ddb/db_command.c:337 #4 0xf0101452 in db_command_loop () at ../../ddb/db_command.c:462 #5 0xf0103b43 in db_trap (type=12, code=0) at ../../ddb/db_trap.c:71 #6 0xf017f1e1 in kdb_trap (type=12, code=0, regs=0xf3c92ba0) at ../../i386/i386/db_interface.c:158 #7 0xf0189caf in trap_fatal (frame=0xf3c92ba0) at ../../i386/i386/trap.c:808 #8 0xf0189758 in trap_pfault (frame=0xf3c92ba0, usermode=0) at ../../i386/i386/trap.c:706 #9 0xf01893bf in trap (frame={tf_es = 16, tf_ds = 16, tf_edi = -261512882, tf_esi = -261512882, tf_ebp = -204919792, tf_isp = -204919864, tf_ebx = -260967680, tf_edx = -261640192, tf_ecx = 0, tf_eax = 301390, tf_trapno = 12, tf_err = 0, tf_eip = -202084920, tf_cs = 8, tf_eflags = 66198, tf_esp = -260967680, tf_ss = -260960512}) at ../../i386/i386/trap.c:345 #10 0xf3f46dc8 in ?? () #11 0xf3f448e8 in ?? () #12 0xf012e824 in vfs_cache_lookup (ap=0xf3c92e28) at vnode_if.h:55 #13 0xf013032d in lookup (ndp=0xf3c92ea8) at vnode_if.h:31 #14 0xf012fe1c in namei (ndp=0xf3c92ea8) at ../../kern/vfs_lookup.c:154 #15 0xf0134a2c in stat (p=0xf067bc00, uap=0xf3c92f84) at ../../kern/vfs_syscalls.c:1552 #16 0xf0189f79 in syscall (frame={tf_es = 39, tf_ds = 39, tf_edi = -272659648, tf_esi = -272659136, tf_ebp = -272659736, tf_isp = -204918828, tf_ebx = -272661784, tf_edx = 407830, tf_ecx = 407944, tf_eax = 188, tf_trapno = 22, tf_err = 7, tf_eip = 537570533, tf_cs = 31, tf_eflags = 642, tf_esp = -272661920, tf_ss = 39}) at ../../i386/i386/trap.c:962 #17 0x200aace5 in ?? () #18 0x21c4a in ?? () #19 0x22742 in ?? () #20 0x203ea in ?? () #21 0x2f2ae in ?? () #22 0x165c7 in ?? () #23 0x16215 in ?? () #24 0x1333f in ?? () #25 0x3a69 in ?? () #26 0x2df5 in ?? () #27 0x10e8 in ?? () (kgdb) q -- In theory, theory is better than practice. In practice, it isn't. James Raynard, Edinburgh, Scotland. http://www.freebsd.org/~jraynard/