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Date:   Thu, 10 Aug 2023 08:48:31 -0700
From:   Nathan Chancellor <nathan@kernel.org>
To:     Borislav Petkov <bp@alien8.de>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Subject: Re: Hang when booting guest kernels compiled with clang after SRSO
 mitigations
Message-ID: <20230810154831.GA38495@dev-arch.thelio-3990X>
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On Thu, Aug 10, 2023 at 05:14:10PM +0200, Borislav Petkov wrote:
> On Thu, Aug 10, 2023 at 08:07:06AM -0700, Nathan Chancellor wrote:
> >   [    2.408527] microcode: microcode updated early to new patch_level=0x0830107a
> 
> Hm, a wild guess: can you boot the *host* with "dis_ucode_ldr" on the
> kernel cmdline and see if it still reproduces?

It does.

> Also, can you bisect rc5..master to see which exact patch is causing
> this?

Sure thing. I at least isolated it to the SRSO merge, so I will just
bisect that to see the exact commit that causes this.

Cheers,
Nathan