> On Wed, 28 Nov 2007, Remko Lodder wrote: >> Hello, >> >> So as per Jeff's information, can someone from the -current >> list either contact jeff or try to resolve the problems >> mentioned? :) > > This is a longstanding bug which also exists in RELENG_6. It turns out > that 'sysctl kern.ttys' after a terminal device is removed could trigger > this panic reliably. For example, do 'sysctl kern.ttys' multiple times > after detaching an USB serial-to-rs232 cable or a PCMCIA modem card. > Suddenly, it all becomes quite clear. I use umodem and ucom for my cellphone (motorola razr v3) mostly to charge it, but occasionally to provide my laptop with mobile connectivity. So I add/remove a USB tty almost every night. My only question is: up until recently the panic was a double panic and hang, with no vmcore available. then all of a sudden it was a single panic where savecore was actually useful. I wonder what changed (or even if it's the same panic) If this is a known and longstanding bug, I'll just use a wall charger for my cellphone, and leave everyone alone. Thanks for the input! Jeff > Alternatively, following script would demo the panic if you don't have > a physically removable terminal device: > > #!/bin/sh > # > # Warning! Running this script as root will panic your CURRENT box... > # > while true; do > kldload dcons > kldunload dcons > ls /dev > sysctl kern.ttys > sleep 1 > done > > This seems to be a race between devfs and destroy_dev(), Cc'ing kib_at_ > since he probably has more clues in this area. > >> -------- Original Message -------- >> Subject: Re: kern/118258 sysctl causing panics on 7.0-xxx >> Date: Wed, 28 Nov 2007 14:50:02 GMT >> From: Jeff Palmer <jeff_at_rexdb.com> >> Reply-To: Jeff Palmer <jeff_at_rexdb.com> >> To: freebsd-bugs_at_FreeBSD.org >> >> The following reply was made to PR kern/118258; it has been noted by >> GNATS. >> >> From: Jeff Palmer <jeff_at_rexdb.com> >> To: bug-followup_at_freebsd.org >> Cc: >> Subject: Re: kern/118258 sysctl causing panics on 7.0-xxx >> Date: Wed, 28 Nov 2007 09:28:47 -0500 >> >> Caught another vmcore,=20 >> this time simply from 'sysctl -a' >> This one showed debugging data from the if_wpi driver on the terminal >> immediately before the panic. >> >> Since the wpi driver is in -CURRENT (and not in 7.3-BETA3) I'm uncertain >> if this should actually be filed as a PR, or just brought up on the >> current_at_ list. >> I'm not certain it's directly related to the wpi driver, so until >> informed otherwise, I'll just keep submitting followups to this PR as I >> can. >> >> Thanks, >> >> Jeff Palmer >> >> >> Laptop# kgdb /usr/obj/usr/src/sys/GENERIC/kernel.debug >> /var/crash/vmcore.= >> 1 >> [GDB will not be able to debug user-mode threads: >> /usr/lib/libthread_db.so: Undefined symbol " >> ps_pglobal_lookup"] >> GNU gdb 6.1.1 [FreeBSD] >> Copyright 2004 Free Software Foundation, Inc. >> GDB is free software, covered by the GNU General Public License, and you >> = >> are >> welcome to change it and/or distribute copies of it under certain >> conditions. >> Type "show copying" to see the conditions. >> There is absolutely no warranty for GDB. Type "show warranty" for >> detail= >> s. >> This GDB was configured as "i386-marcel-freebsd". >> >> Unread portion of the kernel message buffer: >> >> >> Fatal trap 12: page fault while in kernel mode >> cpuid =3D 1; apic id =3D 01 >> fault virtual address =3D 0x18264 >> fault code =3D supervisor read, page not present >> instruction pointer =3D 0x20:0xc06e6a11 >> stack pointer =3D 0x28:0xe76e9aa4 >> frame pointer =3D 0x28:0xe76e9aa4 >> code segment =3D base 0x0, limit 0xfffff, type 0x1b >> =3D DPL 0, pres 1, def32 1, gran 1 >> processor eflags =3D interrupt enabled, resume, IOPL =3D 0 >> current process =3D 53221 (sysctl) >> trap number =3D 12 >> panic: page fault >> cpuid =3D 1 >> Uptime: 1d5h15m17s >> Physical memory: 1001 MB >> Dumping 210 MB: 195 179 163 147 131 115 99 83 67 51 35 19 3 >> >> #0 doadump () at pcpu.h:195 >> 195 pcpu.h: No such file or directory. >> in pcpu.h >> (kgdb) bt >> #0 doadump () at pcpu.h:195 >> #1 0xc0750c17 in boot (howto=3D260) at >> /usr/src/sys/kern/kern_shutdown.c= >> :409 >> #2 0xc0750ed9 in panic (fmt=3DVariable "fmt" is not available. >> ) at /usr/src/sys/kern/kern_shutdown.c:563 >> #3 0xc0a1542c in trap_fatal (frame=3D0xe76e9a64, eva=3D98916) >> at /usr/src/sys/i386/i386/trap.c:872 >> #4 0xc0a156b0 in trap_pfault (frame=3D0xe76e9a64, usermode=3D0, >> eva=3D98= >> 916) >> at /usr/src/sys/i386/i386/trap.c:785 >> #5 0xc0a16025 in trap (frame=3D0xe76e9a64) at >> /usr/src/sys/i386/i386/trap.c:463 >> #6 0xc09fc04b in calltrap () at /usr/src/sys/i386/i386/exception.s:139 >> #7 0xc06e6a11 in dev2udev (x=3D0xc50f4b00) at >> /usr/src/sys/fs/devfs/devfs_vnops.c:1322 >> #8 0xc0790e22 in sysctl_kern_ttys (oidp=3D0xc0b4b7e0, arg1=3D0x0, >> arg2=3D= >> 0, >> req=3D0xe76e9ba4) >> at /usr/src/sys/kern/tty.c:3078 >> #9 0xc075a457 in sysctl_root (oidp=3DVariable "oidp" is not available. >> ) at /usr/src/sys/kern/kern_sysctl.c:1306 >> #10 0xc075a5a4 in userland_sysctl (td=3D0xc5049210, name=3D0xe76e9c14, >> namelen=3D2, old=3D0x0, >> oldlenp=3D0xbfbfe334, inkernel=3D0, new=3D0x0, newlen=3D0, >> retval=3D0xe76e9c10, flags=3D0) >> at /usr/src/sys/kern/kern_sysctl.c:1401 >> #11 0xc075b33e in __sysctl (td=3D0xc5049210, uap=3D0xe76e9cfc) >> at /usr/src/sys/kern/kern_sysctl.c:1336 >> #12 0xc0a15a05 in syscall (frame=3D0xe76e9d38) at >> /usr/src/sys/i386/i386/trap.c:1008 >> #13 0xc09fc0b0 in Xint0x80_syscall () at >> /usr/src/sys/i386/i386/exception.s:196 >> #14 0x00000033 in ?? () >> Previous frame inner to this frame (corrupt stack?) >> (kgdb) list >> 196 call syscall >> 197 add $4, %esp >> 198 MEXITCOUNT >> 199 jmp doreti >> 200 >> 201 ENTRY(fork_trampoline) >> 202 pushl %esp /* trapframe pointer */ >> 203 pushl %ebx /* arg1 */ >> 204 pushl %esi /* function */ >> 205 call fork_exit >> (kgdb) > -- > Cheers, > > Tai-hwa Liang > _______________________________________________ > freebsd-current_at_freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe_at_freebsd.org" > > !DSPAM:8,474f8d94174311715688600! > > >Received on Fri Nov 30 2007 - 07:46:48 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:39:23 UTC