[Xen-devel] [PATCH] x86/AMD: correct certain Fam17 checks

["Jan Beulich" <JBeulich@xxxxxxxx>]

Commit 3157bb4e13 ("Add MSR support for various feature AMD processor
families") converted certain checks for Fam11 to include families all
the way up to Fam17. The commit having no description, it is hard to
tell whether this was a mechanical dec->hex conversion mistake, or
indeed intended. In any event the NB_CFG handling needs to be restricted
to Fam16 and below: Fam17 doesn't have such an MSR anymore.

A non-MMCFG extended config space access mechanism still appears to
exist, but code to deal with it will need to be written down the road,
when it can actually be tested.

Reported-by: Pu Wen <puwen@xxxxxxxx>
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
I'm also not sure whether e.g. init_amd()'s C1E disabling is still
applicable to Fam17.

--- a/xen/arch/x86/hvm/ioreq.c
+++ b/xen/arch/x86/hvm/ioreq.c
@@ -1288,7 +1288,7 @@ struct hvm_ioreq_server *hvm_select_iore
              d->arch.cpuid->x86_vendor == X86_VENDOR_AMD &&
              (x86_fam = get_cpu_family(
                  d->arch.cpuid->basic.raw_fms, NULL, NULL)) > 0x10 &&
-             x86_fam <= 0x17 )
+             x86_fam < 0x17 )
         {
             uint64_t msr_val;
 
--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -195,7 +195,7 @@ static bool pci_cfg_ok(struct domain *cu
     /* AMD extended configuration space access? */
     if ( CF8_ADDR_HI(currd->arch.pci_cf8) &&
          boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
-         boot_cpu_data.x86 >= 0x10 && boot_cpu_data.x86 <= 0x17 )
+         boot_cpu_data.x86 >= 0x10 && boot_cpu_data.x86 < 0x17 )
     {
         uint64_t msr_val;
 
@@ -1015,7 +1015,7 @@ static int write_msr(unsigned int reg, u
 
     case MSR_AMD64_NB_CFG:
         if ( boot_cpu_data.x86_vendor != X86_VENDOR_AMD ||
-             boot_cpu_data.x86 < 0x10 || boot_cpu_data.x86 > 0x17 )
+             boot_cpu_data.x86 < 0x10 || boot_cpu_data.x86 >= 0x17 )
             break;
         if ( !is_hardware_domain(currd) || !is_pinned_vcpu(curr) )
             return X86EMUL_OKAY;
@@ -1028,7 +1028,7 @@ static int write_msr(unsigned int reg, u
 
     case MSR_FAM10H_MMIO_CONF_BASE:
         if ( boot_cpu_data.x86_vendor != X86_VENDOR_AMD ||
-             boot_cpu_data.x86 < 0x10 || boot_cpu_data.x86 > 0x17 )
+             boot_cpu_data.x86 < 0x10 || boot_cpu_data.x86 >= 0x17 )
             break;
         if ( !is_hardware_domain(currd) || !is_pinned_vcpu(curr) )
             return X86EMUL_OKAY;





_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel