Re: Panic on CPU 0: FATAL TRAP: vec 7, #NM[0000]

[ChrisD <chris@xxxxxxxxxxxx>]

So, you think it's a problem with fc36?

-------- Original message --------

From: Andrew Cooper <Andrew.Cooper3@xxxxxxxxxx>

Date: 7/18/22 6:25 PM (GMT-05:00)

To: chris@xxxxxxxxxxxx, xen-devel@xxxxxxxxxxxxxxxxxxxx

Cc: Jan Beulich <jbeulich@xxxxxxxx>, Michael Young <m.a.young@xxxxxxxxxxxx>

Subject: Re: Panic on CPU 0: FATAL TRAP: vec 7, #NM[0000]

On 18/07/2022 22:31, chris@xxxxxxxxxxxx wrote:
> I am trying to run Xen-4.16.1-4.fc36 on Fedora 36 on a brand new Lenovo
> ThinkStation p620, but I keep getting the following error booting the
> Xen kernel.
>
> Panic on CPU 0:
> FATAL TRAP: vec 7, #NM[0000]
>
> Version info:
> Name        : xen
> Version     : 4.16.1
> Release     : 4.fc36

So https://koji.fedoraproject.org/koji/buildinfo?buildID=1991182 should
be the binary build in use, and looking at the debug syms, it really
does have:

ffff82d040439c80 <amd_iommu_init>:
...
ffff82d04043a00c:       0f 6e c2                movd   %edx,%mm0
ffff82d04043a00f:       0f 62 c0                punpckldq %mm0,%mm0
ffff82d04043a012:       49 89 87 c0 00 00 00    mov    %rax,0xc0(%r15)
ffff82d04043a019:       41 0f 7f 87 d0 00 00    movq   %mm0,0xd0(%r15)
ffff82d04043a020:       00

So hardware is correct - this build of Xen is nonsense.

The binary is also full of .annobin_ stuff which appears to be some kind
of GCC plugin for watermarking.

Michael: Any idea what's going on here?  Something has caused GCC to
emit some MMX logic which is ultimately why things exploded, but this
probably means that some of the build CFLAGS got dropped.

Thanks,

~Andrew