[PATCH 2/2 v6] kdump,vmcoreinfo: Export the value of sme mask to vmcoreinfo

[Lianbo Jiang]

For AMD machine with SME feature, makedumpfile tools need to know
whether the crashed kernel was encrypted or not. If SME is enabled
in the first kernel, the crashed kernel's page table(pgd/pud/pmd/pte)
contains the memory encryption mask, so makedumpfile needs to remove
the sme mask to obtain the true physical address.

Signed-off-by: Lianbo Jiang <liji...@redhat.com>
---
 arch/x86/kernel/machine_kexec_64.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/x86/kernel/machine_kexec_64.c 
b/arch/x86/kernel/machine_kexec_64.c
index 4c8acdfdc5a7..bc4108096b18 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -352,10 +352,13 @@ void machine_kexec(struct kimage *image)
 
 void arch_crash_save_vmcoreinfo(void)
 {
+       u64 sme_mask = sme_me_mask;
+
        VMCOREINFO_NUMBER(phys_base);
        VMCOREINFO_SYMBOL(init_top_pgt);
        vmcoreinfo_append_str("NUMBER(pgtable_l5_enabled)=%d\n",
                        pgtable_l5_enabled());
+       VMCOREINFO_NUMBER(sme_mask);
 
 #ifdef CONFIG_NUMA
        VMCOREINFO_SYMBOL(node_data);
-- 
2.17.1