Re: 7.0_BETA crashes on some Amazon EC2 instances

[John Nemeth <jnemeth%cue.bc.ca@localhost>]

On Oct 27,  2:35pm, Jeff Rizzo wrote:
}
} I'm currently trying to get 7.0_BETA images up on Amazon EC2, but I'm 
} seeing a very high rate of crashes.  (~50% during boot).  Has anyone 
} else seen this?
} 
} Here's a crash:
} 
} NetBSD 7.0_BETA (XEN3_DOMU.201410252300Z)
} total memory = 615 MB
} avail memory = 586 MB
} kern.module.path=/stand/amd64/7.0/modules
} mainbus0 (root)
} hypervisor0 at mainbus0: Xen version 3.4.3.amazon
} vcpu0 at hypervisor0: Intel(R) Xeon(R) CPU E5-2650 0 @ 2.00GHz, id 0x206d7
} 
} [snip]
} 
} fatal privileged instruction fault in supervisor mode
} trap type 0 code 0 rip ffffffff8012e3a2 cs e030 rflags 10246 cr2 
} 7f7ff781db1c ilevel 8 rsp ffffa0001c7feec8
} curlwp 0xffffa000017c4120 pid 14.1 lowest kstack 0xffffa0001c7fc2c0
} kernel: privileged instruction fault trap, code=0
} Stopped in pid 14.1 (ps) at     netbsd:xrstor+0xa:      fxsavel
} xrstor() at netbsd:xrstor+0xa

     This is the same basic problem as in PR/49150.  However, that
problem was seen with an AMD CPU.  The quick fix would be to adjust
sys/arch/x86/x86/identcpu.c:1.46 and do a pullup.  Longer term, it
looks like we might need to do dsl@'s suggestion of catching the
trap and handling it at run time.  However, I have no idea how to
do that.  I'm not famailier with FPU stuff or that area of the
kernel.

}-- End of excerpt from Jeff Rizzo