Re: repeated failure to properly shutdown

[bch <brad.harder%gmail.com@localhost>]

Alright -- I'm in (recompiled kernel with proper options, induced
crash, loaded w/ gdb). What frame and data are we interested in ?


-bch



/usr/obj/sys/arch/amd64/compile/GENERIC
kamloops# gdb ./netbsd.gdb
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Reading symbols from ./netbsd.gdb...done.
(gdb) target kvm /var/crash/netbsd.15.core
0xffffffff80119935 in cpu_reboot (howto=howto@entry=260,
bootstr=bootstr@entry=0x0) at
/usr/src/sys/arch/amd64/amd64/machdep.c:672
672                     dumpsys();
(gdb) bt
#0  0xffffffff80119935 in cpu_reboot (howto=howto@entry=260,
bootstr=bootstr@entry=0x0) at
/usr/src/sys/arch/amd64/amd64/machdep.c:672
#1  0xffffffff80874aac in vpanic (fmt=0xffffffff80f85c20 "kernel
%sassertion \"%s\" failed: file \"%s\", line %d double free of buffer?
bp=%p, b_freelistindex=%d\n", ap=ap@entry=0xfffffe8041106b98)
    at /usr/src/sys/kern/subr_prf.c:342
#2  0xffffffff80bb59f5 in kern_assert
(fmt=fmt@entry=0xffffffff80f85c20 "kernel %sassertion \"%s\" failed:
file \"%s\", line %d double free of buffer? bp=%p,
b_freelistindex=%d\n")
    at /usr/src/sys/lib/libkern/kern_assert.c:51
#3  0xffffffff808b2dcd in binstailfree (dp=0xffffffff8130c9c0
<bufqueues>, bp=0xfffffe811d4245a0) at /usr/src/sys/kern/vfs_bio.c:333
#4  brelsel (bp=0xfffffe811d4245a0, set=<optimized out>) at
/usr/src/sys/kern/vfs_bio.c:1092
#5  0xffffffff808d0786 in wapbl_discard (wl=0xfffffe81081e2e08) at
/usr/src/sys/kern/vfs_wapbl.c:661
#6  0xffffffff808ca91d in vclean (vp=vp@entry=0xfffffe8108412008) at
/usr/src/sys/kern/vfs_vnode.c:1032
#7  0xffffffff808cc57d in vgone (vp=vp@entry=0xfffffe8108412008) at
/usr/src/sys/kern/vfs_vnode.c:1152
#8  0xffffffff808be525 in vflush (mp=mp@entry=0xfffffe81081c2008,
skipvp=skipvp@entry=0x0, flags=flags@entry=2) at
/usr/src/sys/kern/vfs_mount.c:531
#9  0xffffffff80735844 in tmpfs_unmount (mp=0xfffffe81081c2008,
mntflags=524288) at /usr/src/sys/fs/tmpfs/tmpfs_vfsops.c:243
#10 0xffffffff808c1d95 in VFS_UNMOUNT (mp=mp@entry=0xfffffe81081c2008,
a=a@entry=524288) at /usr/src/sys/kern/vfs_subr.c:1296
#11 0xffffffff808be69d in dounmount (mp=mp@entry=0xfffffe81081c2008,
flags=524288, l=l@entry=0xfffffe811ae34880) at
/usr/src/sys/kern/vfs_mount.c:856
#12 0xffffffff808c5155 in sys_unmount (l=0xfffffe811ae34880,
uap=0xfffffe8041106f00, retval=<optimized out>) at
/usr/src/sys/kern/vfs_syscalls.c:617
#13 0xffffffff8013e6ac in sy_call (rval=0xfffffe8041106eb0,
uap=0xfffffe8041106f00, l=0xfffffe811ae34880, sy=0xffffffff811ca9d0
<sysent+528>) at /usr/src/sys/sys/syscallvar.h:65
#14 sy_invoke (code=22, rval=0xfffffe8041106eb0,
uap=0xfffffe8041106f00, l=0xfffffe811ae34880, sy=0xffffffff811ca9d0
<sysent+528>) at /usr/src/sys/sys/syscallvar.h:94
#15 syscall (frame=0xfffffe8041106f00) at
/usr/src/sys/arch/x86/x86/syscall.c:156
#16 0xffffffff80100761 in Xsyscall ()


On 7/21/16, Robert Swindells <rjs%fdy2.co.uk@localhost> wrote:
>
> bch <brad.harder%gmail.com@localhost> wrote:
>>I have kernel cores, but I'm not as familiar w/ crash(8) as gdb.
>
> You can use gdb instead of crash if you want:
>
> <http://www.netbsd.org/docs/kernel/#debugging_a_kernel_crash_dump>
>