Re: [PATCH v1 04/26] x86/sev: Add the host SEV-SNP initialization support

From: Borislav Petkov <bp@alien8.de>
To: Michael Roth <michael.roth@amd.com>
Cc: x86@kernel.org, kvm@vger.kernel.org, linux-coco@lists.linux.dev,
	linux-mm@kvack.org, linux-crypto@vger.kernel.org,
	linux-kernel@vger.kernel.org, tglx@linutronix.de,
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	hpa@zytor.com, ardb@kernel.org, pbonzini@redhat.com,
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	luto@kernel.org, dave.hansen@linux.intel.com, slp@redhat.com,
	pgonda@google.com, peterz@infradead.org,
	srinivas.pandruvada@linux.intel.com, rientjes@google.com,
	tobin@ibm.com, vbabka@suse.cz, kirill@shutemov.name,
	ak@linux.intel.com, tony.luck@intel.com,
	sathyanarayanan.kuppuswamy@linux.intel.com, alpergun@google.com,
	jarkko@kernel.org, ashish.kalra@amd.com, nikunj.dadhania@amd.com,
	pankaj.gupta@amd.com, liam.merwick@oracle.com,
	zhi.a.wang@intel.com, Brijesh Singh <brijesh.singh@amd.com>
Subject: Re: [PATCH v1 04/26] x86/sev: Add the host SEV-SNP initialization support
Date: Fri, 5 Jan 2024 22:27:42 +0100	[thread overview]
Message-ID: <20240105212742.GFZZh0TpMZEmah1bBH@fat_crate.local> (raw)
In-Reply-To: <20231230161954.569267-5-michael.roth@amd.com>

On Sat, Dec 30, 2023 at 10:19:32AM -0600, Michael Roth wrote:
> +static int __init __snp_rmptable_init(void)

I already asked a year ago:

https://lore.kernel.org/all/Y9ubi0i4Z750gdMm@zn.tnic/

why is the __ version - __snp_rmptable_init - carved out but crickets.
It simply gets ignored. :-\

So let me do it myself, diff below.

Please add to the next version:

Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>

after incorporating all the changes.

Thx.

---

diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c
index 566bb6f39665..feed65f80776 100644
--- a/arch/x86/virt/svm/sev.c
+++ b/arch/x86/virt/svm/sev.c
@@ -155,19 +155,25 @@ bool snp_probe_rmptable_info(void)
  * described in the SNP_INIT_EX firmware command description in the SNP
  * firmware ABI spec.
  */
-static int __init __snp_rmptable_init(void)
+static int __init snp_rmptable_init(void)
 {
-	u64 rmptable_size;
 	void *rmptable_start;
+	u64 rmptable_size;
 	u64 val;
 
+	if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP))
+		return 0;
+
+	if (!amd_iommu_snp_en)
+		return 0;
+
 	if (!probed_rmp_size)
-		return 1;
+		goto nosnp;
 
 	rmptable_start = memremap(probed_rmp_base, probed_rmp_size, MEMREMAP_WB);
 	if (!rmptable_start) {
 		pr_err("Failed to map RMP table\n");
-		return 1;
+		goto nosnp;
 	}
 
 	/*
@@ -195,20 +201,6 @@ static int __init __snp_rmptable_init(void)
 	rmptable = (struct rmpentry *)rmptable_start;
 	rmptable_max_pfn = rmptable_size / sizeof(struct rmpentry) - 1;
 
-	return 0;
-}
-
-static int __init snp_rmptable_init(void)
-{
-	if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP))
-		return 0;
-
-	if (!amd_iommu_snp_en)
-		return 0;
-
-	if (__snp_rmptable_init())
-		goto nosnp;
-
 	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/rmptable_init:online", __snp_enable, NULL);
 
 	return 0;

-- 
Regards/Gruss,
    Boris.

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