linux-kernel - Re: v6.13-rc1: Internal error: Oops - Undefined instruction: 0000000002000000 [#1] SMP

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Z05cuuMMurzp1jx5@linux.dev>
Date: Mon, 2 Dec 2024 17:19:54 -0800
From: Oliver Upton <oliver.upton@...ux.dev>
To: Vitaly Chikunov <vt@...linux.org>
Cc: Marc Zyngier <maz@...nel.org>, Will Deacon <will@...nel.org>,
	james.morse@....com, linux-arm-kernel@...ts.infradead.org,
	Catalin Marinas <catalin.marinas@....com>,
	linux-kernel@...r.kernel.org, mark.rutland@....com
Subject: Re: v6.13-rc1: Internal error: Oops - Undefined instruction:
 0000000002000000 [#1] SMP

On Tue, Dec 03, 2024 at 01:31:19AM +0300, Vitaly Chikunov wrote:
> Marc,
> 
> On Mon, Dec 02, 2024 at 04:07:03PM +0000, Marc Zyngier wrote:
> > On Mon, 02 Dec 2024 15:59:40 +0000,
> > Vitaly Chikunov <vt@...linux.org> wrote:
> > > 
> > > Marc,
> > > 
> > > On Mon, Dec 02, 2024 at 03:53:59PM +0000, Marc Zyngier wrote:
> > > >
> > > > What the log doesn't say is what the host is. Is it 6.13-rc1 as well?
> > > 
> > > No, host is 6.6.60.
> > 
> > Right. I wouldn't be surprised if:
> > 
> > - this v6.6 kernel doesn't hide the MPAM feature as it should (and
> >   that's proably something we should backport)
> 
> How to confirm this? Currently I cannot find any (case-insensitive)
> "MPAM" files in /sys, nor mpam string in /proc/cpuinfo, nor MPAM strings
> in `strace -v` (as it decodes some KVM ioctls) of qemu process.

If you can attach to the QEMU gdbstub of the VM, info registers will
dump ~everything.

If the value of ID_AA64PFR0_EL1.MPAM (bits 43:40) is nonzero then the
host KVM is erroneously advertising MPAM to the guest.

-- 
Thanks,
Oliver