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

From: Borislav Petkov
Date: Fri Jan 05 2024 - 16:28:48 EST


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@xxxxxxx/

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@xxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>

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