Re: Panic "Fatal trap 18: integer divide fault while in kernel mode"

On Thursday 30 April 2009 04:29 pm, David Wolfskill wrote:
> On Thu, Apr 30, 2009 at 03:51:59PM -0400, Jung-uk Kim wrote:
> > ...
> >
> > > >> db> bt
> > > >> Tracing pid 0 tid 100000 td 0xc0d43610
> > > >> cpu_topo(2,c1420d34,c081ff07,c1420d58,c0820042,...) at
> > > >> cpu_topo+0x43 smp_topo(c0804378,2,c4145a5c,fffffff,0,...) at
> > > >> smp_topo+0x10b
> > > >> sched_setup(0,141ec00,141ec00,141e000,1425000,...) at
> > > >> sched_setup+0x1a mi_startup() at mi_startup+0x96
> > > >> begin() at begin+0x2c
> > > >
> > > > My guess is that (cpu_cores * cpu_logical) somehow equals to
> > > > zero.
> > >
> > > That was masked earlier by  additional checks on zero,
> > > and now that routine moved to the separate function
> > > (and to separate call path from subr_smp.c:mp_start()
> > > which seems not to be called).
> > >
> > > > Have you by a chance saved this crash dump?
> > > > I think that t would be interesting to look at it in kgdb.
>
> I was unable to save a dump; sorry -- "panic" merely sat there. 
> Since the kernel had yet to have probed any devices (that I can
> tell), that may have had something to do with it.
>
> > Please try the attached patch.
> >
> > Jung-uk Kim
> >
> > --- sys/amd64/amd64/mp_machdep.c	(revision 191699)
> > +++ sys/amd64/amd64/mp_machdep.c	(working copy)
> > _at__at_ -214,6 +214,8 _at__at_
> >  		else if (type == CPUID_TYPE_CORE)
> >  			cpu_cores = cnt;
> >  	}
> > +	if (cpu_cores == 0)
> > +		cpu_cores = 1;
> >  	if (cpu_logical == 0)
> >  		cpu_logical = 1;
> >  	cpu_cores /= cpu_logical;
> > --- sys/i386/i386/mp_machdep.c	(revision 191699)
> > +++ sys/i386/i386/mp_machdep.c	(working copy)
> > _at__at_ -267,6 +267,8 _at__at_
> >  		else if (type == CPUID_TYPE_CORE)
> >  			cpu_cores = cnt;
> >  	}
> > +	if (cpu_cores == 0)
> > +		cpu_cores = 1;
> >  	if (cpu_logical == 0)
> >  		cpu_logical = 1;
> >  	cpu_cores /= cpu_logical;
>
> OK; I tried, but the symptoms appear unchanged:
>
> ...
>  �  Select option, [Enter] for default     �
>  �  or [Space] to pause timer  9           �
>  읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
>
>
> GDB: no debug ports present
> KDB: debugger backends: ddb
> KDB: current backend: ddb
> SMAP type=01 base=0000000000000000 len=000000000009fc00
> SMAP type=02 base=000000000009fc00 len=0000000000000400
> SMAP type=01 base=0000000000100000 len=000000002fee2800
> SMAP type=02 base=000000002ffe2800 len=000000000001d800
> SMAP type=02 base=00000000feda0000 len=0000000000060000
> SMAP type=02 base=00000000ffb80000 len=0000000000480000
> Copyright (c) 1992-2009 The FreeBSD Project.
> Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993,
> 1994 The Regents of the University of California. All rights
> reserved. FreeBSD is a registered trademark of The FreeBSD
> Foundation. FreeBSD 8.0-CURRENT #1027 r191682M: Thu Apr 30 13:19:50
> PDT 2009
> root_at_d254.dwolf.juniper.net.:/common/S4/obj/usr/src/sys/CANARY
> WARNING: WITNESS option enabled, expect reduced performance.
> Preloaded elf kernel "/boot/kernel/kernel" at 0xc1131000.
> Preloaded elf module "/boot/kernel/linux.ko" at 0xc113114c.
> Preloaded elf module "/boot/kernel/if_an.ko" at 0xc11311f8.
> Preloaded elf module "/boot/kernel/if_wi.ko" at 0xc11312a4.
> Preloaded elf module "/boot/kernel/radeon.ko" at 0xc1131350.
> Preloaded elf module "/boot/kernel/drm.ko" at 0xc11313fc.
> Timecounter "i8254" frequency 1193182 Hz quality 0
> Calibrating TSC clock ... TSC clock: 2392953980 Hz
> CPU: Mobile Intel(R) Pentium(R) 4 - M CPU 2.40GHz (2392.95-MHz
> 686-class CPU) Origin = "GenuineIntel"  Id = 0xf27  Stepping = 7
>  
> Features=0xbfebf9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE
>,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE
>> Features2=0x400<CNXT-ID>
>
> Instruction TLB: 4 KB, 2 MB or 4 MB pages, fully associative, 128
> entries Data TLB: 4 KB or 4 MB pages, fully associative, 64 entries
> 1st-level data cache: 8 KB, 4-way set associative, sectored cache,
> 64 byte line size Trace cache: 12K-uops, 8-way set associative
> 2nd-level cache: 512 KB, 8-way set associative, sectored cache, 64
> byte line size real memory  = 805306368 (768 MB)
> Physical memory chunk(s):
> 0x0000000000001000 - 0x000000000009efff, 647168 bytes (158 pages)
> 0x0000000000100000 - 0x00000000003fffff, 3145728 bytes (768 pages)
> 0x0000000001425000 - 0x000000002f2d9fff, 770396160 bytes (188085
> pages) avail memory = 769626112 (733 MB)
> bios32: Found BIOS32 Service Directory header at 0xc00ffe80
> bios32: Entry = 0xffe90 (c00ffe90)  Rev = 0  Len = 1
> pcibios: PCI BIOS entry at 0xf0000+0xbfee
> pnpbios: Found PnP BIOS data at 0xc00fe2d0
> pnpbios: Entry = f0000:e2f4  Rev = 1.0
> pnpbios: Event flag at 4b4
> Other BIOS signatures found:
>
>
> Fatal trap 18: integer divide fault while in kernel mode
> cpuid = 0; apic id = 00
> instruction pointer     = 0x20:0xc0b3c9f3
> stack pointer           = 0x28:0xc1420d00
> frame pointer           = 0x28:0xc1420d20
> code segment            = base 0x0, limit 0xfffff, type 0x1b
>                         = DPL 0, pres 1, def32 1, gran 1
> processor eflags        = interrupt enabled, resume, IOPL = 0
> current process         = 0 (swapper)
> [thread pid 0 tid 100000 ]
> Stopped at      cpu_topo+0x43:  idivl   %ecx,%eax
> db> bt
> Tracing pid 0 tid 100000 td 0xc0d43690
> cpu_topo(2,c1420d34,c081ff07,c1420d58,c0820042,...) at
> cpu_topo+0x43 smp_topo(c0804378,2,c4145a5c,fffffff,0,...) at
> smp_topo+0x10b sched_setup(0,141ec00,141ec00,141e000,1425000,...)
> at sched_setup+0x1a mi_startup() at mi_startup+0x96
> begin() at begin+0x2c
> db>

Okay, then please try this instead.

Jung-uk Kim