3 files changed, 36 insertions, 25 deletions

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 03b4cc0ec3a7..66ca906aa790 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -836,6 +836,16 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
 	}
 
 	/*
+	 * If SSBD is controlled by the SPEC_CTRL MSR, then set the proper
+	 * bit in the mask to allow guests to use the mitigation even in the
+	 * case where the host does not enable it.
+	 */
+	if (static_cpu_has(X86_FEATURE_SPEC_CTRL_SSBD) ||
+	    static_cpu_has(X86_FEATURE_AMD_SSBD)) {
+		x86_spec_ctrl_mask |= SPEC_CTRL_SSBD;
+	}
+
+	/*
 	 * We have three CPU feature flags that are in play here:
 	 *  - X86_BUG_SPEC_STORE_BYPASS - CPU is susceptible.
 	 *  - X86_FEATURE_SSBD - CPU is able to turn off speculative store bypass
@@ -852,7 +862,6 @@ static enum ssb_mitigation __init __ssb_select_mitigation(void)
 			x86_amd_ssb_disable();
 		} else {
 			x86_spec_ctrl_base |= SPEC_CTRL_SSBD;
-			x86_spec_ctrl_mask |= SPEC_CTRL_SSBD;
 			wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
 		}
 	}
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index a813987b5552..cb0fdcaf1415 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -789,13 +789,16 @@ static struct syscore_ops mc_syscore_ops = {
 	.resume			= mc_bp_resume,
 };
 
-static int mc_cpu_online(unsigned int cpu)
+static int mc_cpu_starting(unsigned int cpu)
 {
-	struct device *dev;
-
-	dev = get_cpu_device(cpu);
 	microcode_update_cpu(cpu);
 	pr_debug("CPU%d added\n", cpu);
+	return 0;
+}
+
+static int mc_cpu_online(unsigned int cpu)
+{
+	struct device *dev = get_cpu_device(cpu);
 
 	if (sysfs_create_group(&dev->kobj, &mc_attr_group))
 		pr_err("Failed to create group for CPU%d\n", cpu);
@@ -872,7 +875,9 @@ int __init microcode_init(void)
 		goto out_ucode_group;
 
 	register_syscore_ops(&mc_syscore_ops);
-	cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:online",
+	cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",
+				  mc_cpu_starting, NULL);
+	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online",
 				  mc_cpu_online, mc_cpu_down_prep);
 
 	pr_info("Microcode Update Driver: v%s.", DRIVER_VERSION);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 2131b8bbaad7..2f4824793798 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -796,8 +796,12 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
 			      struct seq_file *seq, void *v)
 {
 	struct rdt_resource *r = of->kn->parent->priv;
-	u32 sw_shareable = 0, hw_shareable = 0;
-	u32 exclusive = 0, pseudo_locked = 0;
+	/*
+	 * Use unsigned long even though only 32 bits are used to ensure
+	 * test_bit() is used safely.
+	 */
+	unsigned long sw_shareable = 0, hw_shareable = 0;
+	unsigned long exclusive = 0, pseudo_locked = 0;
 	struct rdt_domain *dom;
 	int i, hwb, swb, excl, psl;
 	enum rdtgrp_mode mode;
@@ -842,10 +846,10 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
 		}
 		for (i = r->cache.cbm_len - 1; i >= 0; i--) {
 			pseudo_locked = dom->plr ? dom->plr->cbm : 0;
-			hwb = test_bit(i, (unsigned long *)&hw_shareable);
-			swb = test_bit(i, (unsigned long *)&sw_shareable);
-			excl = test_bit(i, (unsigned long *)&exclusive);
-			psl = test_bit(i, (unsigned long *)&pseudo_locked);
+			hwb = test_bit(i, &hw_shareable);
+			swb = test_bit(i, &sw_shareable);
+			excl = test_bit(i, &exclusive);
+			psl = test_bit(i, &pseudo_locked);
 			if (hwb && swb)
 				seq_putc(seq, 'X');
 			else if (hwb && !swb)
@@ -2486,26 +2490,19 @@ out_destroy:
  */
 static void cbm_ensure_valid(u32 *_val, struct rdt_resource *r)
 {
-	/*
-	 * Convert the u32 _val to an unsigned long required by all the bit
-	 * operations within this function. No more than 32 bits of this
-	 * converted value can be accessed because all bit operations are
-	 * additionally provided with cbm_len that is initialized during
-	 * hardware enumeration using five bits from the EAX register and
-	 * thus never can exceed 32 bits.
-	 */
-	unsigned long *val = (unsigned long *)_val;
+	unsigned long val = *_val;
 	unsigned int cbm_len = r->cache.cbm_len;
 	unsigned long first_bit, zero_bit;
 
-	if (*val == 0)
+	if (val == 0)
 		return;
 
-	first_bit = find_first_bit(val, cbm_len);
-	zero_bit = find_next_zero_bit(val, cbm_len, first_bit);
+	first_bit = find_first_bit(&val, cbm_len);
+	zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
 
 	/* Clear any remaining bits to ensure contiguous region */
-	bitmap_clear(val, zero_bit, cbm_len - zero_bit);
+	bitmap_clear(&val, zero_bit, cbm_len - zero_bit);
+	*_val = (u32)val;
 }
 
 /*