linux-kernel - Re: [PATCH v4 1/3] x86/sev: Add new dump_rmp parameter to snp_leak

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Message-ID: <20250912155852.GBaMRDPEhr2hbAXavs@fat_crate.local>
Date: Fri, 12 Sep 2025 17:58:52 +0200
From: Borislav Petkov <bp@...en8.de>
To: seanjc@...gle.com
Cc: Ashish Kalra <Ashish.Kalra@....com>, tglx@...utronix.de,
	mingo@...hat.com, dave.hansen@...ux.intel.com, x86@...nel.org,
	hpa@...or.com, pbonzini@...hat.com, thomas.lendacky@....com,
	herbert@...dor.apana.org.au, nikunj@....com, davem@...emloft.net,
	aik@....com, ardb@...nel.org, john.allen@....com,
	michael.roth@....com, Neeraj.Upadhyay@....com,
	linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
	linux-crypto@...r.kernel.org
Subject: Re: [PATCH v4 1/3] x86/sev: Add new dump_rmp parameter to
 snp_leak_pages() API

On Wed, Sep 10, 2025 at 10:55:24PM +0000, Ashish Kalra wrote:
> From: Ashish Kalra <ashish.kalra@....com>
> 
> When leaking certain page types, such as Hypervisor Fixed (HV_FIXED)
> pages, it does not make sense to dump RMP contents for the 2MB range of
> the page(s) being leaked. In the case of HV_FIXED pages, this is not an
> error situation where the surrounding 2MB page RMP entries can provide
> debug information.
> 
> Add new __snp_leak_pages() API with dump_rmp bool parameter to support
> continue adding pages to the snp_leaked_pages_list but not issue
> dump_rmpentry().
> 
> Make snp_leak_pages() a wrapper for the common case which also allows
> existing users to continue to dump RMP entries.
> 
> Suggested-by: Thomas Lendacky <Thomas.Lendacky@....com>
> Suggested-by: Sean Christopherson <seanjc@...gle.com>
> Signed-off-by: Ashish Kalra <ashish.kalra@....com>
> ---
>  arch/x86/include/asm/sev.h | 8 +++++++-
>  arch/x86/virt/svm/sev.c    | 7 ++++---
>  2 files changed, 11 insertions(+), 4 deletions(-)

Sean, lemme know if I should carry this through tip.

Or, if you wanna take it:

Acked-by: Borislav Petkov (AMD) <bp@...en8.de>

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette