Re: panic: Lock so_rcv_sx not exclusively locked

Thanks for the bug report. It looks like this can probably be fixed by
simply not calling sbunlock if sblock failed.  I anticipate this being
fixed shortly.


 -Kip


On Jan 28, 2008 10:08 AM, Jos Backus <jos_at_catnook.com> wrote:
> Recent -current kernels can reliably be made to panic by killing npviewer.bin.
> Right before killing, npviewer.bin shows up like this in top:
>
>  6288 jos           1  45    5 62844K 36788K so_rcv   0:08  0.00% npviewer.bin
>
> lizzy:~/crash% kgdb /usr/obj/usr/src/sys/LIZZY/kernel.debug vmcore.1
> kgdb: kvm_nlist(_stopped_cpus):
> kgdb: kvm_nlist(_stoppcbs):
> [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 details.
> This GDB was configured as "i386-marcel-freebsd".
>
> Unread portion of the kernel message buffer:
> panic: Lock so_rcv_sx not exclusively locked _at_ /usr/src/sys/kern/uipc_sockbuf.c:157
>
> Uptime: 5h23m39s
> Physical memory: 1527 MB
> Dumping 247 MB: 232 216 200 184 168 152 136 120 104 88 72 56 40 24 8
>
> #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  0xc05435ef in boot (howto=260) at /usr/src/sys/kern/kern_shutdown.c:417
> #2  0xc0543867 in panic (fmt=Variable "fmt" is not available.
> ) at /usr/src/sys/kern/kern_shutdown.c:571
> #3  0xc054a427 in _sx_assert (sx=0xc4fb89a0, what=4,
>     file=0xc06d49ca "/usr/src/sys/kern/uipc_sockbuf.c", line=157)
>     at /usr/src/sys/kern/kern_sx.c:931
> #4  0xc054a8da in _sx_xunlock (sx=0xc4fb89a0,
>     file=0xc06d49ca "/usr/src/sys/kern/uipc_sockbuf.c", line=157)
>     at /usr/src/sys/kern/kern_sx.c:316
> #5  0xc0595444 in sbunlock (sb=0xc4fb8968)
>     at /usr/src/sys/kern/uipc_sockbuf.c:157
> #6  0xc0598245 in sorflush (so=0xc4fb8918)
>     at /usr/src/sys/kern/uipc_socket.c:1902
> #7  0xc05982df in soshutdown (so=0xc4fb8918, how=2)
>     at /usr/src/sys/kern/uipc_socket.c:1866
> #8  0xc059ce86 in shutdown (td=0xc4b31880, uap=0xe7219c58)
>     at /usr/src/sys/kern/uipc_syscalls.c:1248
> #9  0xc07ffa80 in ?? ()
> #10 0xc4b31880 in ?? ()
> #11 0xe7219c58 in ?? ()
> #12 0x00000008 in ?? ()
> #13 0x00000000 in ?? ()
> #14 0x00000000 in ?? ()
> #15 0xc103d800 in ?? ()
> #16 0x00000c1e in ?? ()
> #17 0x00000000 in ?? ()
> #18 0xc4e25488 in ?? ()
> #19 0xc5007e9c in ?? ()
> #20 0x00000000 in ?? ()
> #21 0x00000000 in ?? ()
> #22 0xe7219c72 in ?? ()
> #23 0x00000004 in ?? ()
> #24 0x80000000 in ?? ()
> #25 0xe7219c8c in ?? ()
> ---Type <return> to continue, or q <return> to quit---
> #26 0xc06a1a44 in __qdivrem (uq=Unhandled dwarf expression opcode 0x93
> ) at /usr/src/sys/libkern/qdivrem.c:186
> #27 0xc0697b93 in syscall (frame=0xe7219d38)
>     at /usr/src/sys/i386/i386/trap.c:1034
> #28 0xc06818b0 in Xint0x80_syscall () at /usr/src/sys/i386/i386/exception.s:203
> #29 0x00000033 in ?? ()
> Previous frame inner to this frame (corrupt stack?)
> (kgdb)
>
>
> --
> Jos Backus
> jos at catnook.com
> _______________________________________________
> 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"
>