diff options
Diffstat (limited to 'arch/x86/kernel/amd_nb.c')
| -rw-r--r-- | arch/x86/kernel/amd_nb.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/kernel/amd_nb.c b/arch/x86/kernel/amd_nb.c index 9fe9972d2071..04712fd0c964 100644 --- a/arch/x86/kernel/amd_nb.c +++ b/arch/x86/kernel/amd_nb.c @@ -405,7 +405,6 @@ bool __init early_is_amd_nb(u32 device) struct resource *amd_get_mmconfig_range(struct resource *res) { - u32 address; u64 base, msr; unsigned int segn_busn_bits; @@ -413,13 +412,11 @@ struct resource *amd_get_mmconfig_range(struct resource *res) boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) return NULL; - /* assume all cpus from fam10h have mmconfig */ - if (boot_cpu_data.x86 < 0x10) + /* Assume CPUs from Fam10h have mmconfig, although not all VMs do */ + if (boot_cpu_data.x86 < 0x10 || + rdmsrl_safe(MSR_FAM10H_MMIO_CONF_BASE, &msr)) return NULL; - address = MSR_FAM10H_MMIO_CONF_BASE; - rdmsrl(address, msr); - /* mmconfig is not enabled */ if (!(msr & FAM10H_MMIO_CONF_ENABLE)) return NULL; @@ -582,6 +579,10 @@ static __init void fix_erratum_688(void) static __init int init_amd_nbs(void) { + if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD && + boot_cpu_data.x86_vendor != X86_VENDOR_HYGON) + return 0; + amd_cache_northbridges(); amd_cache_gart(); |