Re: [qemu64,+smep,+smap] Kernel panic - not syncing: No working init found.

H. Peter Anvin
2014-02-13T14:55:47Z

On 02/13/2014 04:45 AM, Fengguang Wu wrote:
> Greetings,
>
> I find that when running
>
> qemu-system-x86_64 -cpu qemu64,+smep,+smap
>
> Some kernels will 100% produce this error, where the error code
> -13,-14 are -EACCES and -EFAULT:
>
> Any ideas?
>

I notice this is a non-SMAP kernel:

# CONFIG_X86_SMAP is not set

If the kernel turns on SMAP in CR4 even though SMAP isn't enabled in the
kernel, that is a kernel bug. If Qemu enforces SMAP even if it is
turned off in CR4, that would be a Qemu bug. I have reproduced the
failure locally and an am considering both possibilities now.

-hpa