xen/arch/x86/e820.c: Read the MTRR caps and default type after restoring

The MTRR capabilities and default type were read before the MTRRs were restored in slaunch flow. The restoration itself updated the MTRR default type MSR, so the mtrr_top_of_ram had invalid state in mtrr_cap and mtrr_def variables. Move reading those MSRs after MTRRs are restored in slaunch flow. Signed-off-by: Michał Żygowski <[email protected]>
TrenchBoot · Aug 17, 2024 · 13cbcd7 · 13cbcd7
1 parent 97a4b4a
commit 13cbcd7
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/xen/arch/x86/e820.c b/xen/arch/x86/e820.c
@@ -454,12 +454,12 @@ static uint64_t __init mtrr_top_of_ram(void)
     ASSERT(paddr_bits);
     addr_mask = ((1ull << paddr_bits) - 1) & PAGE_MASK;
 
-    rdmsrl(MSR_MTRRcap, mtrr_cap);
-    rdmsrl(MSR_MTRRdefType, mtrr_def);
-
     if ( slaunch_active && boot_cpu_data.x86_vendor == X86_VENDOR_INTEL )
         txt_restore_mtrrs(e820_verbose);
 
+    rdmsrl(MSR_MTRRcap, mtrr_cap);
+    rdmsrl(MSR_MTRRdefType, mtrr_def);
+
     if ( e820_verbose )
         printk(" MTRR cap: %"PRIx64" type: %"PRIx64"\n", mtrr_cap, mtrr_def);