linux-kernel - Re: [PATCH 4/7] x86/kexec: Disable kexec/kdump on platforms with TDX partial write erratum

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Message-ID: <c68c29ba-fe81-4411-b976-7867120e38ca@suse.com>
Date: Wed, 8 Oct 2025 20:13:41 +0200
From: Jürgen Groß <jgross@...e.com>
To: Dave Hansen <dave.hansen@...el.com>,
 "Reshetova, Elena" <elena.reshetova@...el.com>,
 "Annapurve, Vishal" <vannapurve@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>,
 "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
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 "Chen, Farrah" <farrah.chen@...el.com>, Binbin Wu <binbin.wu@...ux.intel.com>
Subject: Re: [PATCH 4/7] x86/kexec: Disable kexec/kdump on platforms with TDX
 partial write erratum

On 08.10.25 17:40, Dave Hansen wrote:
> On 10/7/25 06:31, Jürgen Groß wrote:>
>> If we can't come to an agreement that kdump should be allowed in
>> spite of a potential #MC, maybe we could disable kdump only if TDX
>> guests have been active on the machine before?
> 
> How would we determine that?
> 
> We can't just call the TDX module to see because it might have been
> running before but got shut down.

Ah, okay, I didn't think of that.

Then we could add a kernel boot parameter to let the user opt-in for kexec
being possible in spite of the potential #MC. I think this should cover it.


Juergen

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