The RMP table is probed early in the boot process before max_pfn has been
set, so the logic to check if the RMP covers all of system memory is not
valid.
Move the RMP memory coverage check from snp_probe_rmptable_info() into
snp_rmptable_init(), which is well after max_pfn has been set.
Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support")
Signed-off-by: Tom Lendacky <[email protected]>
---
arch/x86/virt/svm/sev.c | 45 ++++++++++++++++++++---------------------
1 file changed, 22 insertions(+), 23 deletions(-)
diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c
index 0ae10535c699..0636fc5279e6 100644
--- a/arch/x86/virt/svm/sev.c
+++ b/arch/x86/virt/svm/sev.c
@@ -61,7 +61,7 @@ struct rmpentry {
/* Mask to apply to a PFN to get the first PFN of a 2MB page */
#define PFN_PMD_MASK GENMASK_ULL(63, PMD_SHIFT - PAGE_SHIFT)
-static u64 probed_rmp_base, probed_rmp_size;
+static u64 probed_rmp_base, probed_rmp_end, probed_rmp_size;
static struct rmpentry *rmptable __ro_after_init;
static u64 rmptable_max_pfn __ro_after_init;
@@ -120,7 +120,7 @@ static __init void snp_enable(void *arg)
bool snp_probe_rmptable_info(void)
{
- u64 max_rmp_pfn, calc_rmp_sz, rmp_sz, rmp_base, rmp_end;
+ u64 rmp_sz, rmp_base, rmp_end;
rdmsrl(MSR_AMD64_RMP_BASE, rmp_base);
rdmsrl(MSR_AMD64_RMP_END, rmp_end);
@@ -137,28 +137,12 @@ bool snp_probe_rmptable_info(void)
rmp_sz = rmp_end - rmp_base + 1;
- /*
- * Calculate the amount the memory that must be reserved by the BIOS to
- * address the whole RAM, including the bookkeeping area. The RMP itself
- * must also be covered.
- */
- max_rmp_pfn = max_pfn;
- if (PHYS_PFN(rmp_end) > max_pfn)
- max_rmp_pfn = PHYS_PFN(rmp_end);
-
- calc_rmp_sz = (max_rmp_pfn << 4) + RMPTABLE_CPU_BOOKKEEPING_SZ;
-
- if (calc_rmp_sz > rmp_sz) {
- pr_err("Memory reserved for the RMP table does not cover full system RAM (expected 0x%llx got 0x%llx)\n",
- calc_rmp_sz, rmp_sz);
- return false;
- }
-
probed_rmp_base = rmp_base;
+ probed_rmp_end = rmp_end;
probed_rmp_size = rmp_sz;
pr_info("RMP table physical range [0x%016llx - 0x%016llx]\n",
- probed_rmp_base, probed_rmp_base + probed_rmp_size - 1);
+ probed_rmp_base, probed_rmp_end);
return true;
}
@@ -206,9 +190,8 @@ void __init snp_fixup_e820_tables(void)
*/
static int __init snp_rmptable_init(void)
{
+ u64 max_rmp_pfn, calc_rmp_sz, rmptable_size, val;
void *rmptable_start;
- u64 rmptable_size;
- u64 val;
if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))
return 0;
@@ -219,10 +202,26 @@ static int __init snp_rmptable_init(void)
if (!probed_rmp_size)
goto nosnp;
+ /*
+ * Calculate the amount the memory that must be reserved by the BIOS to
+ * address the whole RAM, including the bookkeeping area. The RMP itself
+ * must also be covered.
+ */
+ max_rmp_pfn = max_pfn;
+ if (PHYS_PFN(probed_rmp_end) > max_pfn)
+ max_rmp_pfn = PHYS_PFN(probed_rmp_end);
+
+ calc_rmp_sz = (max_rmp_pfn << 4) + RMPTABLE_CPU_BOOKKEEPING_SZ;
+ if (calc_rmp_sz > probed_rmp_size) {
+ pr_err("Memory reserved for the RMP table does not cover full system RAM (expected 0x%llx got 0x%llx)\n",
+ calc_rmp_sz, probed_rmp_size);
+ 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;
}
/*
--
2.43.2
On 05/06/2024 16:38, Tom Lendacky wrote:
> The RMP table is probed early in the boot process before max_pfn has been
> set, so the logic to check if the RMP covers all of system memory is not
> valid.
>
> Move the RMP memory coverage check from snp_probe_rmptable_info() into
> snp_rmptable_init(), which is well after max_pfn has been set.
>
> Fixes: 216d106c7ff7 ("x86/sev: Add SEV-SNP host initialization support")
> Signed-off-by: Tom Lendacky <[email protected]>
Reviewed-by: Liam Merwick <[email protected]>
> ---
> arch/x86/virt/svm/sev.c | 45 ++++++++++++++++++++---------------------
> 1 file changed, 22 insertions(+), 23 deletions(-)
>