Merge tag 'x86_cpu_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 cpu updates from Borislav Petkov:

 - Split MTRR and PAT init code to accomodate at least Xen PV and TDX
   guests which do not get MTRRs exposed but only PAT. (TDX guests do
   not support the cache disabling dance when setting up MTRRs so they
   fall under the same category)

   This is a cleanup work to remove all the ugly workarounds for such
   guests and init things separately (Juergen Gross)

 - Add two new Intel CPUs to the list of CPUs with "normal" Energy
   Performance Bias, leading to power savings

 - Do not do bus master arbitration in C3 (ARB_DISABLE) on modern
   Centaur CPUs

* tag 'x86_cpu_for_v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  x86/mtrr: Make message for disabled MTRRs more descriptive
  x86/pat: Handle TDX guest PAT initialization
  x86/cpuid: Carve out all CPUID functionality
  x86/cpu: Switch to cpu_feature_enabled() for X86_FEATURE_XENPV
  x86/cpu: Remove X86_FEATURE_XENPV usage in setup_cpu_entry_area()
  x86/cpu: Drop 32-bit Xen PV guest code in update_task_stack()
  x86/cpu: Remove unneeded 64-bit dependency in arch_enter_from_user_mode()
  x86/cpufeatures: Add X86_FEATURE_XENPV to disabled-features.h
  x86/acpi/cstate: Optimize ARB_DISABLE on Centaur CPUs
  x86/mtrr: Simplify mtrr_ops initialization
  x86/cacheinfo: Switch cache_ap_init() to hotplug callback
  x86: Decouple PAT and MTRR handling
  x86/mtrr: Add a stop_machine() handler calling only cache_cpu_init()
  x86/mtrr: Let cache_aps_delayed_init replace mtrr_aps_delayed_init
  x86/mtrr: Get rid of __mtrr_enabled bool
  x86/mtrr: Simplify mtrr_bp_init()
  x86/mtrr: Remove set_all callback from struct mtrr_ops
  x86/mtrr: Disentangle MTRR init from PAT init
  x86/mtrr: Move cache control code to cacheinfo.c
  x86/mtrr: Split MTRR-specific handling from cache dis/enabling
  ...

30 files changed, 538 insertions, 662 deletions

diff --git a/arch/x86/include/asm/cacheinfo.h b/arch/x86/include/asm/cacheinfo.h
index 86b2e0dcc4bf..ce9685fc78d8 100644
--- a/arch/x86/include/asm/cacheinfo.h
+++ b/arch/x86/include/asm/cacheinfo.h
@@ -2,7 +2,20 @@
 #ifndef _ASM_X86_CACHEINFO_H
 #define _ASM_X86_CACHEINFO_H
 
+/* Kernel controls MTRR and/or PAT MSRs. */
+extern unsigned int memory_caching_control;
+#define CACHE_MTRR 0x01
+#define CACHE_PAT  0x02
+
 void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu);
 void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu);
 
+void cache_disable(void);
+void cache_enable(void);
+void set_cache_aps_delayed_init(bool val);
+bool get_cache_aps_delayed_init(void);
+void cache_bp_init(void);
+void cache_bp_restore(void);
+void cache_aps_init(void);
+
 #endif /* _ASM_X86_CACHEINFO_H */
diff --git a/arch/x86/include/asm/cpuid.h b/arch/x86/include/asm/cpuid.h
index 70b2db18165e..9bee3e7bf973 100644
--- a/arch/x86/include/asm/cpuid.h
+++ b/arch/x86/include/asm/cpuid.h
@@ -1,13 +1,132 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * CPUID-related helpers/definitions
- *
- * Derived from arch/x86/kvm/cpuid.c
  */
 
 #ifndef _ASM_X86_CPUID_H
 #define _ASM_X86_CPUID_H
 
+#include <asm/string.h>
+
+struct cpuid_regs {
+	u32 eax, ebx, ecx, edx;
+};
+
+enum cpuid_regs_idx {
+	CPUID_EAX = 0,
+	CPUID_EBX,
+	CPUID_ECX,
+	CPUID_EDX,
+};
+
+#ifdef CONFIG_X86_32
+extern int have_cpuid_p(void);
+#else
+static inline int have_cpuid_p(void)
+{
+	return 1;
+}
+#endif
+static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
+				unsigned int *ecx, unsigned int *edx)
+{
+	/* ecx is often an input as well as an output. */
+	asm volatile("cpuid"
+	    : "=a" (*eax),
+	      "=b" (*ebx),
+	      "=c" (*ecx),
+	      "=d" (*edx)
+	    : "0" (*eax), "2" (*ecx)
+	    : "memory");
+}
+
+#define native_cpuid_reg(reg)					\
+static inline unsigned int native_cpuid_##reg(unsigned int op)	\
+{								\
+	unsigned int eax = op, ebx, ecx = 0, edx;		\
+								\
+	native_cpuid(&eax, &ebx, &ecx, &edx);			\
+								\
+	return reg;						\
+}
+
+/*
+ * Native CPUID functions returning a single datum.
+ */
+native_cpuid_reg(eax)
+native_cpuid_reg(ebx)
+native_cpuid_reg(ecx)
+native_cpuid_reg(edx)
+
+#ifdef CONFIG_PARAVIRT_XXL
+#include <asm/paravirt.h>
+#else
+#define __cpuid			native_cpuid
+#endif
+
+/*
+ * Generic CPUID function
+ * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
+ * resulting in stale register contents being returned.
+ */
+static inline void cpuid(unsigned int op,
+			 unsigned int *eax, unsigned int *ebx,
+			 unsigned int *ecx, unsigned int *edx)
+{
+	*eax = op;
+	*ecx = 0;
+	__cpuid(eax, ebx, ecx, edx);
+}
+
+/* Some CPUID calls want 'count' to be placed in ecx */
+static inline void cpuid_count(unsigned int op, int count,
+			       unsigned int *eax, unsigned int *ebx,
+			       unsigned int *ecx, unsigned int *edx)
+{
+	*eax = op;
+	*ecx = count;
+	__cpuid(eax, ebx, ecx, edx);
+}
+
+/*
+ * CPUID functions returning a single datum
+ */
+static inline unsigned int cpuid_eax(unsigned int op)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return eax;
+}
+
+static inline unsigned int cpuid_ebx(unsigned int op)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return ebx;
+}
+
+static inline unsigned int cpuid_ecx(unsigned int op)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return ecx;
+}
+
+static inline unsigned int cpuid_edx(unsigned int op)
+{
+	unsigned int eax, ebx, ecx, edx;
+
+	cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return edx;
+}
+
 static __always_inline bool cpuid_function_is_indexed(u32 function)
 {
 	switch (function) {
@@ -31,4 +150,22 @@ static __always_inline bool cpuid_function_is_indexed(u32 function)
 	return false;
 }
 
+#define for_each_possible_hypervisor_cpuid_base(function) \
+	for (function = 0x40000000; function < 0x40010000; function += 0x100)
+
+static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
+{
+	uint32_t base, eax, signature[3];
+
+	for_each_possible_hypervisor_cpuid_base(base) {
+		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
+
+		if (!memcmp(sig, signature, 12) &&
+		    (leaves == 0 || ((eax - base) >= leaves)))
+			return base;
+	}
+
+	return 0;
+}
+
 #endif /* _ASM_X86_CPUID_H */
diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h
index 33d2cd04d254..c862552d7d6d 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -81,6 +81,12 @@
 # define DISABLE_SGX	(1 << (X86_FEATURE_SGX & 31))
 #endif
 
+#ifdef CONFIG_XEN_PV
+# define DISABLE_XENPV		0
+#else
+# define DISABLE_XENPV		(1 << (X86_FEATURE_XENPV & 31))
+#endif
+
 #ifdef CONFIG_INTEL_TDX_GUEST
 # define DISABLE_TDX_GUEST	0
 #else
@@ -98,7 +104,7 @@
 #define DISABLED_MASK5	0
 #define DISABLED_MASK6	0
 #define DISABLED_MASK7	(DISABLE_PTI)
-#define DISABLED_MASK8	(DISABLE_TDX_GUEST)
+#define DISABLED_MASK8	(DISABLE_XENPV|DISABLE_TDX_GUEST)
 #define DISABLED_MASK9	(DISABLE_SGX)
 #define DISABLED_MASK10	0
 #define DISABLED_MASK11	(DISABLE_RETPOLINE|DISABLE_RETHUNK|DISABLE_UNRET)
diff --git a/arch/x86/include/asm/entry-common.h b/arch/x86/include/asm/entry-common.h
index 674ed46d3ced..117903881fe4 100644
--- a/arch/x86/include/asm/entry-common.h
+++ b/arch/x86/include/asm/entry-common.h
@@ -24,8 +24,8 @@ static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs)
 		/*
 		 * For !SMAP hardware we patch out CLAC on entry.
 		 */
-		if (boot_cpu_has(X86_FEATURE_SMAP) ||
-		    (IS_ENABLED(CONFIG_64BIT) && boot_cpu_has(X86_FEATURE_XENPV)))
+		if (cpu_feature_enabled(X86_FEATURE_SMAP) ||
+		    cpu_feature_enabled(X86_FEATURE_XENPV))
 			mask |= X86_EFLAGS_AC;
 
 		WARN_ON_ONCE(flags & mask);
diff --git a/arch/x86/include/asm/memtype.h b/arch/x86/include/asm/memtype.h
index 9ca760e430b9..113b2fa51849 100644
--- a/arch/x86/include/asm/memtype.h
+++ b/arch/x86/include/asm/memtype.h
@@ -6,9 +6,8 @@
 #include <asm/pgtable_types.h>
 
 extern bool pat_enabled(void);
-extern void pat_disable(const char *reason);
-extern void pat_init(void);
-extern void init_cache_modes(void);
+extern void pat_bp_init(void);
+extern void pat_cpu_init(void);
 
 extern int memtype_reserve(u64 start, u64 end,
 		enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm);
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 6bcd5d2dd718..37ff47552bcb 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -793,6 +793,7 @@
 #define ENERGY_PERF_BIAS_PERFORMANCE		0
 #define ENERGY_PERF_BIAS_BALANCE_PERFORMANCE	4
 #define ENERGY_PERF_BIAS_NORMAL			6
+#define ENERGY_PERF_BIAS_NORMAL_POWERSAVE	7
 #define ENERGY_PERF_BIAS_BALANCE_POWERSAVE	8
 #define ENERGY_PERF_BIAS_POWERSAVE		15
 
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index 76d726074c16..f0eeaf6e5f5f 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -25,13 +25,12 @@
 
 #include <uapi/asm/mtrr.h>
 
-void mtrr_bp_init(void);
-
 /*
  * The following functions are for use by other drivers that cannot use
  * arch_phys_wc_add and arch_phys_wc_del.
  */
 # ifdef CONFIG_MTRR
+void mtrr_bp_init(void);
 extern u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform);
 extern void mtrr_save_fixed_ranges(void *);
 extern void mtrr_save_state(void);
@@ -42,12 +41,12 @@ extern int mtrr_add_page(unsigned long base, unsigned long size,
 extern int mtrr_del(int reg, unsigned long base, unsigned long size);
 extern int mtrr_del_page(int reg, unsigned long base, unsigned long size);
 extern void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi);
-extern void mtrr_ap_init(void);
-extern void set_mtrr_aps_delayed_init(void);
-extern void mtrr_aps_init(void);
 extern void mtrr_bp_restore(void);
 extern int mtrr_trim_uncached_memory(unsigned long end_pfn);
 extern int amd_special_default_mtrr(void);
+void mtrr_disable(void);
+void mtrr_enable(void);
+void mtrr_generic_set_state(void);
 #  else
 static inline u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform)
 {
@@ -83,10 +82,11 @@ static inline int mtrr_trim_uncached_memory(unsigned long end_pfn)
 static inline void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi)
 {
 }
-#define mtrr_ap_init() do {} while (0)
-#define set_mtrr_aps_delayed_init() do {} while (0)
-#define mtrr_aps_init() do {} while (0)
+#define mtrr_bp_init() do {} while (0)
 #define mtrr_bp_restore() do {} while (0)
+#define mtrr_disable() do {} while (0)
+#define mtrr_enable() do {} while (0)
+#define mtrr_generic_set_state() do {} while (0)
 #  endif
 
 #ifdef CONFIG_COMPAT
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 67c9d73b31fa..6836c64b9819 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -16,6 +16,7 @@ struct vm86;
 #include <uapi/asm/sigcontext.h>
 #include <asm/current.h>
 #include <asm/cpufeatures.h>
+#include <asm/cpuid.h>
 #include <asm/page.h>
 #include <asm/pgtable_types.h>
 #include <asm/percpu.h>
@@ -146,17 +147,6 @@ struct cpuinfo_x86 {
 	unsigned		initialized : 1;
 } __randomize_layout;
 
-struct cpuid_regs {
-	u32 eax, ebx, ecx, edx;
-};
-
-enum cpuid_regs_idx {
-	CPUID_EAX = 0,
-	CPUID_EBX,
-	CPUID_ECX,
-	CPUID_EDX,
-};
-
 #define X86_VENDOR_INTEL	0
 #define X86_VENDOR_CYRIX	1
 #define X86_VENDOR_AMD		2
@@ -205,45 +195,6 @@ extern void identify_secondary_cpu(struct cpuinfo_x86 *);
 extern void print_cpu_info(struct cpuinfo_x86 *);
 void print_cpu_msr(struct cpuinfo_x86 *);
 
-#ifdef CONFIG_X86_32
-extern int have_cpuid_p(void);
-#else
-static inline int have_cpuid_p(void)
-{
-	return 1;
-}
-#endif
-static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
-				unsigned int *ecx, unsigned int *edx)
-{
-	/* ecx is often an input as well as an output. */
-	asm volatile("cpuid"
-	    : "=a" (*eax),
-	      "=b" (*ebx),
-	      "=c" (*ecx),
-	      "=d" (*edx)
-	    : "0" (*eax), "2" (*ecx)
-	    : "memory");
-}
-
-#define native_cpuid_reg(reg)					\
-static inline unsigned int native_cpuid_##reg(unsigned int op)	\
-{								\
-	unsigned int eax = op, ebx, ecx = 0, edx;		\
-								\
-	native_cpuid(&eax, &ebx, &ecx, &edx);			\
-								\
-	return reg;						\
-}
-
-/*
- * Native CPUID functions returning a single datum.
- */
-native_cpuid_reg(eax)
-native_cpuid_reg(ebx)
-native_cpuid_reg(ecx)
-native_cpuid_reg(edx)
-
 /*
  * Friendlier CR3 helpers.
  */
@@ -578,7 +529,6 @@ static __always_inline bool on_thread_stack(void)
 #ifdef CONFIG_PARAVIRT_XXL
 #include <asm/paravirt.h>
 #else
-#define __cpuid			native_cpuid
 
 static inline void load_sp0(unsigned long sp0)
 {
@@ -589,69 +539,6 @@ static inline void load_sp0(unsigned long sp0)
 
 unsigned long __get_wchan(struct task_struct *p);
 
-/*
- * Generic CPUID function
- * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
- * resulting in stale register contents being returned.
- */
-static inline void cpuid(unsigned int op,
-			 unsigned int *eax, unsigned int *ebx,
-			 unsigned int *ecx, unsigned int *edx)
-{
-	*eax = op;
-	*ecx = 0;
-	__cpuid(eax, ebx, ecx, edx);
-}
-
-/* Some CPUID calls want 'count' to be placed in ecx */
-static inline void cpuid_count(unsigned int op, int count,
-			       unsigned int *eax, unsigned int *ebx,
-			       unsigned int *ecx, unsigned int *edx)
-{
-	*eax = op;
-	*ecx = count;
-	__cpuid(eax, ebx, ecx, edx);
-}
-
-/*
- * CPUID functions returning a single datum
- */
-static inline unsigned int cpuid_eax(unsigned int op)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	cpuid(op, &eax, &ebx, &ecx, &edx);
-
-	return eax;
-}
-
-static inline unsigned int cpuid_ebx(unsigned int op)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	cpuid(op, &eax, &ebx, &ecx, &edx);
-
-	return ebx;
-}
-
-static inline unsigned int cpuid_ecx(unsigned int op)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	cpuid(op, &eax, &ebx, &ecx, &edx);
-
-	return ecx;
-}
-
-static inline unsigned int cpuid_edx(unsigned int op)
-{
-	unsigned int eax, ebx, ecx, edx;
-
-	cpuid(op, &eax, &ebx, &ecx, &edx);
-
-	return edx;
-}
-
 extern void select_idle_routine(const struct cpuinfo_x86 *c);
 extern void amd_e400_c1e_apic_setup(void);
 
@@ -805,24 +692,6 @@ static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
 static inline u32 amd_get_highest_perf(void)		{ return 0; }
 #endif
 
-#define for_each_possible_hypervisor_cpuid_base(function) \
-	for (function = 0x40000000; function < 0x40010000; function += 0x100)
-
-static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
-{
-	uint32_t base, eax, signature[3];
-
-	for_each_possible_hypervisor_cpuid_base(base) {
-		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
-
-		if (!memcmp(sig, signature, 12) &&
-		    (leaves == 0 || ((eax - base) >= leaves)))
-			return base;
-	}
-
-	return 0;
-}
-
 extern unsigned long arch_align_stack(unsigned long sp);
 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h
index c08eb0fdd11f..5c91305d09d2 100644
--- a/arch/x86/include/asm/switch_to.h
+++ b/arch/x86/include/asm/switch_to.h
@@ -66,13 +66,10 @@ static inline void update_task_stack(struct task_struct *task)
 {
 	/* sp0 always points to the entry trampoline stack, which is constant: */
 #ifdef CONFIG_X86_32
-	if (static_cpu_has(X86_FEATURE_XENPV))
-		load_sp0(task->thread.sp0);
-	else
-		this_cpu_write(cpu_tss_rw.x86_tss.sp1, task->thread.sp0);
+	this_cpu_write(cpu_tss_rw.x86_tss.sp1, task->thread.sp0);
 #else
 	/* Xen PV enters the kernel on the thread stack. */
-	if (static_cpu_has(X86_FEATURE_XENPV))
+	if (cpu_feature_enabled(X86_FEATURE_XENPV))
 		load_sp0(task_top_of_stack(task));
 #endif
 }
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 7945eae5b315..401808b47af3 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -52,17 +52,25 @@ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags,
 	if (c->x86_vendor == X86_VENDOR_INTEL &&
 	    (c->x86 > 0xf || (c->x86 == 6 && c->x86_model >= 0x0f)))
 			flags->bm_control = 0;
-	/*
-	 * For all recent Centaur CPUs, the ucode will make sure that each
-	 * core can keep cache coherence with each other while entering C3
-	 * type state. So, set bm_check to 1 to indicate that the kernel
-	 * doesn't need to execute a cache flush operation (WBINVD) when
-	 * entering C3 type state.
-	 */
+
 	if (c->x86_vendor == X86_VENDOR_CENTAUR) {
 		if (c->x86 > 6 || (c->x86 == 6 && c->x86_model == 0x0f &&
-		    c->x86_stepping >= 0x0e))
+		    c->x86_stepping >= 0x0e)) {
+			/*
+			 * For all recent Centaur CPUs, the ucode will make sure that each
+			 * core can keep cache coherence with each other while entering C3
+			 * type state. So, set bm_check to 1 to indicate that the kernel
+			 * doesn't need to execute a cache flush operation (WBINVD) when
+			 * entering C3 type state.
+			 */
 			flags->bm_check = 1;
+			/*
+			 * For all recent Centaur platforms, ARB_DISABLE is a nop.
+			 * Set bm_control to zero to indicate that ARB_DISABLE is
+			 * not required while entering C3 type state.
+			 */
+			flags->bm_control = 0;
+		}
 	}
 
 	if (c->x86_vendor == X86_VENDOR_ZHAOXIN) {
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index c75d75b9f11a..f769d6d08b43 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -983,7 +983,7 @@ static void init_amd(struct cpuinfo_x86 *c)
 			set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
 
 	/* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
-	if (!cpu_has(c, X86_FEATURE_XENPV))
+	if (!cpu_feature_enabled(X86_FEATURE_XENPV))
 		set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
 
 	/*
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 6daf84229548..a8a5033a804d 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1302,7 +1302,7 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
 		return SPECTRE_V2_CMD_AUTO;
 	}
 
-	if (cmd == SPECTRE_V2_CMD_IBRS && boot_cpu_has(X86_FEATURE_XENPV)) {
+	if (cmd == SPECTRE_V2_CMD_IBRS && cpu_feature_enabled(X86_FEATURE_XENPV)) {
 		pr_err("%s selected but running as XenPV guest. Switching to AUTO select\n",
 		       mitigation_options[i].option);
 		return SPECTRE_V2_CMD_AUTO;
@@ -2206,74 +2206,74 @@ static const char * const l1tf_vmx_states[] = {
 static ssize_t l1tf_show_state(char *buf)
 {
 	if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_AUTO)
-		return sprintf(buf, "%s\n", L1TF_DEFAULT_MSG);
+		return sysfs_emit(buf, "%s\n", L1TF_DEFAULT_MSG);
 
 	if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_EPT_DISABLED ||
 	    (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_NEVER &&
 	     sched_smt_active())) {
-		return sprintf(buf, "%s; VMX: %s\n", L1TF_DEFAULT_MSG,
-			       l1tf_vmx_states[l1tf_vmx_mitigation]);
+		return sysfs_emit(buf, "%s; VMX: %s\n", L1TF_DEFAULT_MSG,
+				  l1tf_vmx_states[l1tf_vmx_mitigation]);
 	}
 
-	return sprintf(buf, "%s; VMX: %s, SMT %s\n", L1TF_DEFAULT_MSG,
-		       l1tf_vmx_states[l1tf_vmx_mitigation],
-		       sched_smt_active() ? "vulnerable" : "disabled");
+	return sysfs_emit(buf, "%s; VMX: %s, SMT %s\n", L1TF_DEFAULT_MSG,
+			  l1tf_vmx_states[l1tf_vmx_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
 }
 
 static ssize_t itlb_multihit_show_state(char *buf)
 {
 	if (!boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
 	    !boot_cpu_has(X86_FEATURE_VMX))
-		return sprintf(buf, "KVM: Mitigation: VMX unsupported\n");
+		return sysfs_emit(buf, "KVM: Mitigation: VMX unsupported\n");
 	else if (!(cr4_read_shadow() & X86_CR4_VMXE))
-		return sprintf(buf, "KVM: Mitigation: VMX disabled\n");
+		return sysfs_emit(buf, "KVM: Mitigation: VMX disabled\n");
 	else if (itlb_multihit_kvm_mitigation)
-		return sprintf(buf, "KVM: Mitigation: Split huge pages\n");
+		return sysfs_emit(buf, "KVM: Mitigation: Split huge pages\n");
 	else
-		return sprintf(buf, "KVM: Vulnerable\n");
+		return sysfs_emit(buf, "KVM: Vulnerable\n");
 }
 #else
 static ssize_t l1tf_show_state(char *buf)
 {
-	return sprintf(buf, "%s\n", L1TF_DEFAULT_MSG);
+	return sysfs_emit(buf, "%s\n", L1TF_DEFAULT_MSG);
 }
 
 static ssize_t itlb_multihit_show_state(char *buf)
 {
-	return sprintf(buf, "Processor vulnerable\n");
+	return sysfs_emit(buf, "Processor vulnerable\n");
 }
 #endif
 
 static ssize_t mds_show_state(char *buf)
 {
 	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
-		return sprintf(buf, "%s; SMT Host state unknown\n",
-			       mds_strings[mds_mitigation]);
+		return sysfs_emit(buf, "%s; SMT Host state unknown\n",
+				  mds_strings[mds_mitigation]);
 	}
 
 	if (boot_cpu_has(X86_BUG_MSBDS_ONLY)) {
-		return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
-			       (mds_mitigation == MDS_MITIGATION_OFF ? "vulnerable" :
-			        sched_smt_active() ? "mitigated" : "disabled"));
+		return sysfs_emit(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+				  (mds_mitigation == MDS_MITIGATION_OFF ? "vulnerable" :
+				   sched_smt_active() ? "mitigated" : "disabled"));
 	}
 
-	return sprintf(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
-		       sched_smt_active() ? "vulnerable" : "disabled");
+	return sysfs_emit(buf, "%s; SMT %s\n", mds_strings[mds_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
 }
 
 static ssize_t tsx_async_abort_show_state(char *buf)
 {
 	if ((taa_mitigation == TAA_MITIGATION_TSX_DISABLED) ||
 	    (taa_mitigation == TAA_MITIGATION_OFF))
-		return sprintf(buf, "%s\n", taa_strings[taa_mitigation]);
+		return sysfs_emit(buf, "%s\n", taa_strings[taa_mitigation]);
 
 	if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
-		return sprintf(buf, "%s; SMT Host state unknown\n",
-			       taa_strings[taa_mitigation]);
+		return sysfs_emit(buf, "%s; SMT Host state unknown\n",
+				  taa_strings[taa_mitigation]);
 	}
 
-	return sprintf(buf, "%s; SMT %s\n", taa_strings[taa_mitigation],
-		       sched_smt_active() ? "vulnerable" : "disabled");
+	return sysfs_emit(buf, "%s; SMT %s\n", taa_strings[taa_mitigation],
+			  sched_smt_active() ? "vulnerable" : "disabled");
 }
 
 static ssize_t mmio_stale_data_show_state(char *buf)
@@ -2341,73 +2341,72 @@ static char *pbrsb_eibrs_state(void)
 static ssize_t spectre_v2_show_state(char *buf)
 {
 	if (spectre_v2_enabled == SPECTRE_V2_LFENCE)
-		return sprintf(buf, "Vulnerable: LFENCE\n");
+		return sysfs_emit(buf, "Vulnerable: LFENCE\n");
 
 	if (spectre_v2_enabled == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
-		return sprintf(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");
+		return sysfs_emit(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");
 
 	if (sched_smt_active() && unprivileged_ebpf_enabled() &&
 	    spectre_v2_enabled == SPECTRE_V2_EIBRS_LFENCE)
-		return sprintf(buf, "Vulnerable: eIBRS+LFENCE with unprivileged eBPF and SMT\n");
+		return sysfs_emit(buf, "Vulnerable: eIBRS+LFENCE with unprivileged eBPF and SMT\n");
 
-	return sprintf(buf, "%s%s%s%s%s%s%s\n",
-		       spectre_v2_strings[spectre_v2_enabled],
-		       ibpb_state(),
-		       boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "",
-		       stibp_state(),
-		       boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "",
-		       pbrsb_eibrs_state(),
-		       spectre_v2_module_string());
+	return sysfs_emit(buf, "%s%s%s%s%s%s%s\n",
+			  spectre_v2_strings[spectre_v2_enabled],
+			  ibpb_state(),
+			  boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "",
+			  stibp_state(),
+			  boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "",
+			  pbrsb_eibrs_state(),
+			  spectre_v2_module_string());
 }
 
 static ssize_t srbds_show_state(char *buf)
 {
-	return sprintf(buf, "%s\n", srbds_strings[srbds_mitigation]);
+	return sysfs_emit(buf, "%s\n", srbds_strings[srbds_mitigation]);
 }
 
 static ssize_t retbleed_show_state(char *buf)
 {
 	if (retbleed_mitigation == RETBLEED_MITIGATION_UNRET ||
 	    retbleed_mitigation == RETBLEED_MITIGATION_IBPB) {
-	    if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
-		boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
-		    return sprintf(buf, "Vulnerable: untrained return thunk / IBPB on non-AMD based uarch\n");
+		if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+		    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+			return sysfs_emit(buf, "Vulnerable: untrained return thunk / IBPB on non-AMD based uarch\n");
 
-	    return sprintf(buf, "%s; SMT %s\n",
-			   retbleed_strings[retbleed_mitigation],
-			   !sched_smt_active() ? "disabled" :
-			   spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
-			   spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED ?
-			   "enabled with STIBP protection" : "vulnerable");
+		return sysfs_emit(buf, "%s; SMT %s\n", retbleed_strings[retbleed_mitigation],
+				  !sched_smt_active() ? "disabled" :
+				  spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT ||
+				  spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED ?
+				  "enabled with STIBP protection" : "vulnerable");
 	}
 
-	return sprintf(buf, "%s\n", retbleed_strings[retbleed_mitigation]);
+	return sysfs_emit(buf, "%s\n", retbleed_strings[retbleed_mitigation]);
 }
 
 static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
 			       char *buf, unsigned int bug)
 {
 	if (!boot_cpu_has_bug(bug))
-		return sprintf(buf, "Not affected\n");
+		return sysfs_emit(buf, "Not affected\n");
 
 	switch (bug) {
 	case X86_BUG_CPU_MELTDOWN:
 		if (boot_cpu_has(X86_FEATURE_PTI))
-			return sprintf(buf, "Mitigation: PTI\n");
+			return sysfs_emit(buf, "Mitigation: PTI\n");
 
 		if (hypervisor_is_type(X86_HYPER_XEN_PV))
-			return sprintf(buf, "Unknown (XEN PV detected, hypervisor mitigation required)\n");
+			return sysfs_emit(buf, "Unknown (XEN PV detected, hypervisor mitigation required)\n");
 
 		break;
 
 	case X86_BUG_SPECTRE_V1:
-		return sprintf(buf, "%s\n", spectre_v1_strings[spectre_v1_mitigation]);
+		return sysfs_emit(buf, "%s\n", spectre_v1_strings[spectre_v1_mitigation]);
 
 	case X86_BUG_SPECTRE_V2:
 		return spectre_v2_show_state(buf);
 
 	case X86_BUG_SPEC_STORE_BYPASS:
-		return sprintf(buf, "%s\n", ssb_strings[ssb_mode