kern/52916: vinum causes panic after start/stop/... cycle, easy to reproduce

[Greg 'groggy' Lehey]

The following reply was made to PR kern/52916; it has been noted by GNATS.

From: Greg 'groggy' Lehey <grog at FreeBSD.org>
To: Pawel Malachowski <pawmal at unia.3lo.lublin.pl>
Cc: FreeBSD-gnats-submit at FreeBSD.org
Subject: Re: kern/52916: vinum causes panic after start/stop/... cycle, easy to reproduce
Date: Fri, 6 Jun 2003 14:52:05 +0930

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 On Wednesday,  4 June 2003 at 21:00:24 +0200, Pawel Malachowski wrote:
 > On 4 Jun 2003 at 16:57, Greg 'groggy' Lehey wrote:
 >
 >>>> Description:
 >>> Both 4.8-RELEASE and fresh 4.8-STABLE (on two different machines) catch
 >>> kernel panic when I try something like:
 >>> vinum start;vinum stop;vinum start;vinum stop;vinum start;vinum stop
 >>>
 >>> It is very easy to reproduce.
 >>
 >> I was not able to reproduce it.
 >
 > I've published this script on Polish FreeBSD users group, people confirm
 > their machines are crashing too (about 20-60 start/stop cycles):
 >
 >
 >>> 4.8-STABLE was compiled with debug symbols, unfortunately there is
 >>> no crashdump.
 >>
 >> What's the problem?  Do you have crash dumps enabled?
 >
 > Yes.
 >
 >> grep dump /etc/rc.conf
 > dumpdev=3D"/dev/ad0s2b"
 >> swapinfo
 > Device          1K-blocks     Used    Avail Capacity  Type
 > /dev/ad0s2b       1048448        0  1048448     0%    Interleaved
 >> sysctl kern.dumpdev
 > kern.dumpdev: { major =3D 116, minor =3D 0x30001 }
 >
 > Swap is big enough.
 
 Hmm. =20
 
 >>> fault virtual address   =3D 0xb7
 >>> fault code              =3D supervisor read, page not present
 >>> instruction pointer     =3D 0x8:0xc01bedc8
 >>
 >> This one.
 >
 > `x $eip' shows dscheck+0x104 b8968b
 
 OK, this might give us a clue.
 
 >>> So I compiled vinum statically into kernel,
 >>>
 >>> # vinum start;vinum stop;vinum start;vinum stop;
 >>> ** no drives found: No such file or directory
 >>> Can't unload vinum: No such file or directory
 >>> ** no drives found: No such file or directory
 >>> Can't unload vinum: No such file or directory
 >>>
 >>> and it crashed again with message like this:
 >>>
 >>> vinum: no drives found
 >>> vinum: no drives found
 
 No, that's not a crash message.  That's normal.
 
 I'm guessing this has something to do with md devices.  Do you use
 any?  I don't, and every 'vinum start' created one.  I've committed a
 fix to vinum(8) (revision 1.31.2.6 of src/sbin/vinum/commands.c).
 Please try it and tell me if it fixes the problem.  Here it is again
 to save you cvsupping:
 
 diff -w -u -r1.31.2.5 commands.c
 --- commands.c  4 May 2002 05:04:14 -0000       1.31.2.5
 +++ commands.c  6 Jun 2003 05:08:43 -0000
 @@ -275,6 +275,10 @@
      char reply[32];
      int error;
 =20
 +    if (! isatty (STDIN_FILENO)) {
 +       fprintf (stderr, "Please enter this command from a tty device\n");
 +       return;
 +    }
      printf(" WARNING!  This command will completely wipe out your vinum co=
 nfiguration.\n"
         " All data will be lost.  If you really want to do this, enter the =
 text\n\n"
         " NO FUTURE\n"
 @@ -544,6 +548,7 @@
 =20
             if ((((stat->device_type & DEVSTAT_TYPE_MASK) =3D=3D DEVSTAT_TY=
 PE_DIRECT) /* disk device */
                  || ((stat->device_type & DEVSTAT_TYPE_MASK) =3D=3D DEVSTAT=
 _TYPE_STORARRAY)) /* storage array */
 +           &&((stat->device_type & DEVSTAT_TYPE_IF_MASK) !=3D DEVSTAT_TYPE=
 _IF_OTHER) /* and not md */
             &&((stat->device_type & DEVSTAT_TYPE_PASS) =3D=3D 0) /* and not=
  passthrough */
             &&((stat->device_name[0] !=3D '\0'))) {           /* and it has=
  a name */
                 sprintf(enamelist, "%s%s%d", _PATH_DEV, stat->device_name, =
 stat->unit_number);
 
 
 Greg
 --
 See complete headers for address and phone numbers
 
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