Merge tag 'v6.17-rc3' into togreg

Linux 6.17-rc3

5 files changed, 32 insertions, 16 deletions

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index a5ece6ebe8a7..a6f88ca1a6b4 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1326,8 +1326,8 @@ static const char * const s5_reset_reason_txt[] = {
 
 static __init int print_s5_reset_status_mmio(void)
 {
-	unsigned long value;
 	void __iomem *addr;
+	u32 value;
 	int i;
 
 	if (!cpu_feature_enabled(X86_FEATURE_ZEN))
@@ -1340,12 +1340,16 @@ static __init int print_s5_reset_status_mmio(void)
 	value = ioread32(addr);
 	iounmap(addr);
 
+	/* Value with "all bits set" is an error response and should be ignored. */
+	if (value == U32_MAX)
+		return 0;
+
 	for (i = 0; i < ARRAY_SIZE(s5_reset_reason_txt); i++) {
 		if (!(value & BIT(i)))
 			continue;
 
 		if (s5_reset_reason_txt[i]) {
-			pr_info("x86/amd: Previous system reset reason [0x%08lx]: %s\n",
+			pr_info("x86/amd: Previous system reset reason [0x%08x]: %s\n",
 				value, s5_reset_reason_txt[i]);
 		}
 	}
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index b74bf937cd9f..49ef1b832c1a 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -386,7 +386,6 @@ static bool __init should_mitigate_vuln(unsigned int bug)
 
 	case X86_BUG_SPECTRE_V2:
 	case X86_BUG_RETBLEED:
-	case X86_BUG_SRSO:
 	case X86_BUG_L1TF:
 	case X86_BUG_ITS:
 		return cpu_attack_vector_mitigated(CPU_MITIGATE_USER_KERNEL) ||
@@ -1069,10 +1068,8 @@ static void __init gds_select_mitigation(void)
 	if (gds_mitigation == GDS_MITIGATION_AUTO) {
 		if (should_mitigate_vuln(X86_BUG_GDS))
 			gds_mitigation = GDS_MITIGATION_FULL;
-		else {
+		else
 			gds_mitigation = GDS_MITIGATION_OFF;
-			return;
-		}
 	}
 
 	/* No microcode */
@@ -3184,8 +3181,18 @@ static void __init srso_select_mitigation(void)
 	}
 
 	if (srso_mitigation == SRSO_MITIGATION_AUTO) {
-		if (should_mitigate_vuln(X86_BUG_SRSO)) {
+		/*
+		 * Use safe-RET if user->kernel or guest->host protection is
+		 * required.  Otherwise the 'microcode' mitigation is sufficient
+		 * to protect the user->user and guest->guest vectors.
+		 */
+		if (cpu_attack_vector_mitigated(CPU_MITIGATE_GUEST_HOST) ||
+		    (cpu_attack_vector_mitigated(CPU_MITIGATE_USER_KERNEL) &&
+		     !boot_cpu_has(X86_FEATURE_SRSO_USER_KERNEL_NO))) {
 			srso_mitigation = SRSO_MITIGATION_SAFE_RET;
+		} else if (cpu_attack_vector_mitigated(CPU_MITIGATE_USER_USER) ||
+			   cpu_attack_vector_mitigated(CPU_MITIGATE_GUEST_GUEST)) {
+			srso_mitigation = SRSO_MITIGATION_MICROCODE;
 		} else {
 			srso_mitigation = SRSO_MITIGATION_NONE;
 			return;
diff --git a/arch/x86/kernel/cpu/hygon.c b/arch/x86/kernel/cpu/hygon.c
index 2154f12766fb..1fda6c3a2b65 100644
--- a/arch/x86/kernel/cpu/hygon.c
+++ b/arch/x86/kernel/cpu/hygon.c
@@ -16,6 +16,7 @@
 #include <asm/spec-ctrl.h>
 #include <asm/delay.h>
 #include <asm/msr.h>
+#include <asm/resctrl.h>
 
 #include "cpu.h"
 
@@ -117,6 +118,8 @@ static void bsp_init_hygon(struct cpuinfo_x86 *c)
 			x86_amd_ls_cfg_ssbd_mask = 1ULL << 10;
 		}
 	}
+
+	resctrl_cpu_detect(c);
 }
 
 static void early_init_hygon(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index b4a1f6732a3a..6b868afb26c3 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -48,6 +48,7 @@ static const struct cpuid_bit cpuid_bits[] = {
 	{ X86_FEATURE_PROC_FEEDBACK,		CPUID_EDX, 11, 0x80000007, 0 },
 	{ X86_FEATURE_AMD_FAST_CPPC,		CPUID_EDX, 15, 0x80000007, 0 },
 	{ X86_FEATURE_MBA,			CPUID_EBX,  6, 0x80000008, 0 },
+	{ X86_FEATURE_COHERENCY_SFW_NO,		CPUID_EBX, 31, 0x8000001f, 0 },
 	{ X86_FEATURE_SMBA,			CPUID_EBX,  2, 0x80000020, 0 },
 	{ X86_FEATURE_BMEC,			CPUID_EBX,  3, 0x80000020, 0 },
 	{ X86_FEATURE_TSA_SQ_NO,		CPUID_ECX,  1, 0x80000021, 0 },
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 12ed75c1b567..28e4fd65c9da 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1881,19 +1881,20 @@ long fpu_xstate_prctl(int option, unsigned long arg2)
 #ifdef CONFIG_PROC_PID_ARCH_STATUS
 /*
  * Report the amount of time elapsed in millisecond since last AVX512
- * use in the task.
+ * use in the task. Report -1 if no AVX-512 usage.
  */
 static void avx512_status(struct seq_file *m, struct task_struct *task)
 {
-	unsigned long timestamp = READ_ONCE(x86_task_fpu(task)->avx512_timestamp);
-	long delta;
+	unsigned long timestamp;
+	long delta = -1;
 
-	if (!timestamp) {
-		/*
-		 * Report -1 if no AVX512 usage
-		 */
-		delta = -1;
-	} else {
+	/* AVX-512 usage is not tracked for kernel threads. Don't report anything. */
+	if (task->flags & (PF_KTHREAD | PF_USER_WORKER))
+		return;
+
+	timestamp = READ_ONCE(x86_task_fpu(task)->avx512_timestamp);
+
+	if (timestamp) {
 		delta = (long)(jiffies - timestamp);
 		/*
 		 * Cap to LONG_MAX if time difference > LONG_MAX