Re: panic in softdep_slowdown()

On Tue, Jan 27, 2015 at 11:31:03PM +0300, Gleb Smirnoff wrote:
> Got this in bhyve VM on boot up and mount:
> 
> Starting file system checks:
> /dev/vtbd0p3: FILE SYSTEM CLEAN; SKIPPING CHECKS
> /dev/vtbd0p3: clean, 1617700 free (222876 frags, 174353 blocks, 5.9% fragmentation)
> 
> 
> Fatal trap 18: integer divide fault while in kernel mode
> cpuid = 1; apic id = 01
> instruction pointer     = 0x20:0xffffffff80895d63
> stack pointer           = 0x28:0xfffffe001eb5f220
> frame pointer           = 0x28:0xfffffe001eb5f2b0
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                         = DPL 0, pres 1, long 1, def32 0, gran 1
> processor eflags        = interrupt enabled, resume, IOPL = 0
> current process         = 49 (mount)
> [ thread pid 49 tid 100045 ]
> Stopped at      softdep_slowdown+0x1d3: idivl   %ecx,%eax
> db> bt
> Tracing pid 49 tid 100045 td 0xfffff800026ee000
> softdep_slowdown() at softdep_slowdown+0x1d3/frame 0xfffffe001eb5f2b0
> ffs_truncate() at ffs_truncate+0x1be/frame 0xfffffe001eb5f640
> ufs_setattr() at ufs_setattr+0x4e5/frame 0xfffffe001eb5f6a0
> VOP_SETATTR_APV() at VOP_SETATTR_APV+0x22a/frame 0xfffffe001eb5f710
> VOP_SETATTR() at VOP_SETATTR+0x45/frame 0xfffffe001eb5f760
> vn_truncate() at vn_truncate+0x196/frame 0xfffffe001eb5f870
> fo_truncate() at fo_truncate+0x41/frame 0xfffffe001eb5f8b0
> kern_ftruncate() at kern_ftruncate+0x16d/frame 0xfffffe001eb5f920
> sys_ftruncate() at sys_ftruncate+0x27/frame 0xfffffe001eb5f940
> syscallenter() at syscallenter+0x46e/frame 0xfffffe001eb5f9b0
> amd64_syscall() at amd64_syscall+0x1f/frame 0xfffffe001eb5fab0
> Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe001eb5fab0
> --- syscall (480, FreeBSD ELF64, sys_ftruncate), rip = 0x800b511fa, rsp = 0x7fffffffe998, rbp = 0x7fffffffeb90 ---
> db> call doadump
> Dumping 60 out of 495 MB:..27%..54%..80%
> Dump complete
> = 0
> db>
> 
> I've got the core file.

At least the source line for the panic is needed.
Also, print out the value of stat_flush_threads.