diff --git a/Documentation/admin-guide/hw-vuln/attack_vector_controls.rst b/Documentation/admin-guide/hw-vuln/attack_vector_controls.rst
index 6dd0800..5964901 100644
--- a/Documentation/admin-guide/hw-vuln/attack_vector_controls.rst
+++ b/Documentation/admin-guide/hw-vuln/attack_vector_controls.rst
@@ -215,7 +215,7 @@
 Spectre_v2_user                      X                           X            *       (Note 1)
 SRBDS                 X              X            X              X
 SRSO                  X              X            X              X
-SSB                                                                                   (Note 4)
+SSB                                  X
 TAA                   X              X            X              X            *       (Note 2)
 TSA                   X              X            X              X
 =============== ============== ============ ============= ============== ============ ========
@@ -229,9 +229,6 @@
    3 --  Disables SMT if cross-thread mitigations are fully enabled, the CPU is
    vulnerable, and STIBP is not supported
 
-   4 --  Speculative store bypass is always enabled by default (no kernel
-   mitigation applied) unless overridden with spec_store_bypass_disable option
-
 When an attack-vector is disabled, all mitigations for the vulnerabilities
 listed in the above table are disabled, unless mitigation is required for a
 different enabled attack-vector or a mitigation is explicitly selected via a
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 49ef1b8..af838b8 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -416,6 +416,10 @@ static bool __init should_mitigate_vuln(unsigned int bug)
 		       cpu_attack_vector_mitigated(CPU_MITIGATE_USER_USER) ||
 		       cpu_attack_vector_mitigated(CPU_MITIGATE_GUEST_GUEST) ||
 		       (smt_mitigations != SMT_MITIGATIONS_OFF);
+
+	case X86_BUG_SPEC_STORE_BYPASS:
+		return cpu_attack_vector_mitigated(CPU_MITIGATE_USER_USER);
+
 	default:
 		WARN(1, "Unknown bug %x\n", bug);
 		return false;
@@ -2710,6 +2714,11 @@ static void __init ssb_select_mitigation(void)
 		ssb_mode = SPEC_STORE_BYPASS_DISABLE;
 		break;
 	case SPEC_STORE_BYPASS_CMD_AUTO:
+		if (should_mitigate_vuln(X86_BUG_SPEC_STORE_BYPASS))
+			ssb_mode = SPEC_STORE_BYPASS_PRCTL;
+		else
+			ssb_mode = SPEC_STORE_BYPASS_NONE;
+		break;
 	case SPEC_STORE_BYPASS_CMD_PRCTL:
 		ssb_mode = SPEC_STORE_BYPASS_PRCTL;
 		break;
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 076eaa4..98ae4c3 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -262,7 +262,7 @@ static void early_init_intel(struct cpuinfo_x86 *c)
 	if (c->x86_power & (1 << 8)) {
 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
-	} else if ((c->x86_vfm >= INTEL_P4_PRESCOTT && c->x86_vfm <= INTEL_P4_WILLAMETTE) ||
+	} else if ((c->x86_vfm >= INTEL_P4_PRESCOTT && c->x86_vfm <= INTEL_P4_CEDARMILL) ||
 		   (c->x86_vfm >= INTEL_CORE_YONAH  && c->x86_vfm <= INTEL_IVYBRIDGE)) {
 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 	}
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 097e393..514f633 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -171,8 +171,28 @@ static int cmp_id(const void *key, const void *elem)
 		return 1;
 }
 
+static u32 cpuid_to_ucode_rev(unsigned int val)
+{
+	union zen_patch_rev p = {};
+	union cpuid_1_eax c;
+
+	c.full = val;
+
+	p.stepping  = c.stepping;
+	p.model     = c.model;
+	p.ext_model = c.ext_model;
+	p.ext_fam   = c.ext_fam;
+
+	return p.ucode_rev;
+}
+
 static bool need_sha_check(u32 cur_rev)
 {
+	if (!cur_rev) {
+		cur_rev = cpuid_to_ucode_rev(bsp_cpuid_1_eax);
+		pr_info_once("No current revision, generating the lowest one: 0x%x\n", cur_rev);
+	}
+
 	switch (cur_rev >> 8) {
 	case 0x80012: return cur_rev <= 0x800126f; break;
 	case 0x80082: return cur_rev <= 0x800820f; break;
@@ -749,8 +769,6 @@ static struct ucode_patch *cache_find_patch(struct ucode_cpu_info *uci, u16 equi
 	n.equiv_cpu = equiv_cpu;
 	n.patch_id  = uci->cpu_sig.rev;
 
-	WARN_ON_ONCE(!n.patch_id);
-
 	list_for_each_entry(p, &microcode_cache, plist)
 		if (patch_cpus_equivalent(p, &n, false))
 			return p;
diff --git a/arch/x86/kernel/cpu/topology_amd.c b/arch/x86/kernel/cpu/topology_amd.c
index 843b165..827dd0d 100644
--- a/arch/x86/kernel/cpu/topology_amd.c
+++ b/arch/x86/kernel/cpu/topology_amd.c
@@ -81,20 +81,25 @@ static bool parse_8000_001e(struct topo_scan *tscan, bool has_topoext)
 
 	cpuid_leaf(0x8000001e, &leaf);
 
-	tscan->c->topo.initial_apicid = leaf.ext_apic_id;
-
 	/*
-	 * If leaf 0xb is available, then the domain shifts are set
-	 * already and nothing to do here. Only valid for family >= 0x17.
+	 * If leaf 0xb/0x26 is available, then the APIC ID and the domain
+	 * shifts are set already.
 	 */
-	if (!has_topoext && tscan->c->x86 >= 0x17) {
-		/*
-		 * Leaf 0x80000008 set the CORE domain shift already.
-		 * Update the SMT domain, but do not propagate it.
-		 */
-		unsigned int nthreads = leaf.core_nthreads + 1;
+	if (!has_topoext) {
+		tscan->c->topo.initial_apicid = leaf.ext_apic_id;
 
-		topology_update_dom(tscan, TOPO_SMT_DOMAIN, get_count_order(nthreads), nthreads);
+		/*
+		 * Leaf 0x8000008 sets the CORE domain shift but not the
+		 * SMT domain shift. On CPUs with family >= 0x17, there
+		 * might be hyperthreads.
+		 */
+		if (tscan->c->x86 >= 0x17) {
+			/* Update the SMT domain, but do not propagate it. */
+			unsigned int nthreads = leaf.core_nthreads + 1;
+
+			topology_update_dom(tscan, TOPO_SMT_DOMAIN,
+					    get_count_order(nthreads), nthreads);
+		}
 	}
 
 	store_node(tscan, leaf.nnodes_per_socket + 1, leaf.node_id);