When System Memory Encryption (SME) is enabled, the physical address
space is reduced. Adjust the x86_phys_bits value to reflect this
reduction.

Signed-off-by: Tom Lendacky <thomas.lenda...@amd.com>
---
 arch/x86/kernel/cpu/amd.c |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 5fc5232..35eeeb1 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -613,8 +613,10 @@ static void early_init_amd(struct cpuinfo_x86 *c)
                set_cpu_bug(c, X86_BUG_AMD_E400);
 
        /*
-        * BIOS support is required for SME. If BIOS has not enabled SME
-        * then don't advertise the feature (set in scattered.c)
+        * BIOS support is required for SME. If BIOS has enabld SME then
+        * adjust x86_phys_bits by the SME physical address space reduction
+        * value. If BIOS has not enabled SME then don't advertise the
+        * feature (set in scattered.c).
         */
        if (c->extended_cpuid_level >= 0x8000001f) {
                if (cpu_has(c, X86_FEATURE_SME)) {
@@ -622,8 +624,14 @@ static void early_init_amd(struct cpuinfo_x86 *c)
 
                        /* Check if SME is enabled */
                        rdmsrl(MSR_K8_SYSCFG, msr);
-                       if (!(msr & MSR_K8_SYSCFG_MEM_ENCRYPT))
+                       if (msr & MSR_K8_SYSCFG_MEM_ENCRYPT) {
+                               unsigned int ebx;
+
+                               ebx = cpuid_ebx(0x8000001f);
+                               c->x86_phys_bits -= (ebx >> 6) & 0x3f;
+                       } else {
                                clear_cpu_cap(c, X86_FEATURE_SME);
+                       }
                }
        }
 }


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