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Diffstat (limited to 'arch/x86/kernel/cpu/common.c')
-rw-r--r--arch/x86/kernel/cpu/common.c38
1 files changed, 35 insertions, 3 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 454cdf341..758938c94 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1248,6 +1248,8 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
#define SRSO BIT(5)
/* CPU is affected by GDS */
#define GDS BIT(6)
+/* CPU is affected by Register File Data Sampling */
+#define RFDS BIT(7)
static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(IVYBRIDGE, X86_STEPPING_ANY, SRBDS),
@@ -1275,9 +1277,18 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
VULNBL_INTEL_STEPPINGS(TIGERLAKE, X86_STEPPING_ANY, GDS),
VULNBL_INTEL_STEPPINGS(LAKEFIELD, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RETBLEED),
VULNBL_INTEL_STEPPINGS(ROCKETLAKE, X86_STEPPING_ANY, MMIO | RETBLEED | GDS),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO),
- VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS),
+ VULNBL_INTEL_STEPPINGS(ALDERLAKE, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ALDERLAKE_L, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE_P, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(RAPTORLAKE_S, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ALDERLAKE_N, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_D, X86_STEPPING_ANY, MMIO | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_TREMONT_L, X86_STEPPING_ANY, MMIO | MMIO_SBDS | RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT_D, X86_STEPPING_ANY, RFDS),
+ VULNBL_INTEL_STEPPINGS(ATOM_GOLDMONT_PLUS, X86_STEPPING_ANY, RFDS),
VULNBL_AMD(0x15, RETBLEED),
VULNBL_AMD(0x16, RETBLEED),
@@ -1311,6 +1322,24 @@ static bool arch_cap_mmio_immune(u64 ia32_cap)
ia32_cap & ARCH_CAP_SBDR_SSDP_NO);
}
+static bool __init vulnerable_to_rfds(u64 ia32_cap)
+{
+ /* The "immunity" bit trumps everything else: */
+ if (ia32_cap & ARCH_CAP_RFDS_NO)
+ return false;
+
+ /*
+ * VMMs set ARCH_CAP_RFDS_CLEAR for processors not in the blacklist to
+ * indicate that mitigation is needed because guest is running on a
+ * vulnerable hardware or may migrate to such hardware:
+ */
+ if (ia32_cap & ARCH_CAP_RFDS_CLEAR)
+ return true;
+
+ /* Only consult the blacklist when there is no enumeration: */
+ return cpu_matches(cpu_vuln_blacklist, RFDS);
+}
+
static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
{
u64 ia32_cap = x86_read_arch_cap_msr();
@@ -1419,6 +1448,9 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
setup_force_cpu_bug(X86_BUG_SRSO);
}
+ if (vulnerable_to_rfds(ia32_cap))
+ setup_force_cpu_bug(X86_BUG_RFDS);
+
if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
return;