Re: kern/38293: panic: fp_save ipi didn't

[Simon Burge <simonb%NetBSD.org@localhost>]

Christoph_Egger%gmx.de@localhost wrote:

> The kernel panics in src/sys/arch/amd64/amd64/fpu.c
> with "panic: fp_save ipi didn't"
> 
> In all panics I have got so far, the backtrace is always the same:
> 
> fpusave_lwp() at netbsd:fpusave_lwp+0x7b
> cpu_lwp_free() at netbsd:cpu_lwp_free+0x2c
> exit1() at netbsd:exit1+0x5f1
> sys_exit() at netbsd:sys_exit+0x67
> syscall() at netbsd:syscall+0xa9

I've also just started seeing this too, amd64 with simonb-wapbl branch
from June 19th.  I've seen three so far while running build.sh, and
they've all been of the form:

   breakpoint() at netbsd:breakpoint+0x5 
   panic() at netbsd:panic+0x260 
   fpusave_lwp() at netbsd:fpusave_lwp+0x92 
   cpu_lwp_fork() at netbsd:cpu_lwp_fork+0x41 
   lwp_create() at netbsd:lwp_create+0x24f 
   fork1() at netbsd:fork1+0x45c 
   sys___vfork14() at netbsd:sys___vfork14+0x35 
   syscall() at netbsd:syscall+0x9a 

Note that I've got a couple of printfs in some of the ufs filesystem
functions, so there's quite a lot of console output happening all the
time.  I've not seen this problem without those printfs.  Does these
mean something timing related then?

Cheers,
Simon.