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-rw-r--r--arch/x86/Kconfig11
-rw-r--r--arch/x86/include/asm/cpufeature.h7
-rw-r--r--arch/x86/include/asm/disabled-features.h8
-rw-r--r--arch/x86/include/asm/proto.h1
-rw-r--r--arch/x86/include/asm/smap.h24
-rw-r--r--arch/x86/include/asm/suspend_32.h2
-rw-r--r--arch/x86/include/asm/suspend_64.h12
-rw-r--r--arch/x86/kernel/cpu/bugs.c7
-rw-r--r--arch/x86/kernel/cpu/common.c101
-rw-r--r--arch/x86/kernel/setup.c28
-rw-r--r--arch/x86/mm/Makefile3
-rw-r--r--arch/x86/mm/init_64.c1
-rw-r--r--arch/x86/mm/setup_nx.c62
13 files changed, 101 insertions, 166 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d90a33e96517..84a3a52ed3a0 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1831,17 +1831,6 @@ config ARCH_RANDOM
If supported, this is a high bandwidth, cryptographically
secure hardware random number generator.
-config X86_SMAP
- def_bool y
- prompt "Supervisor Mode Access Prevention" if EXPERT
- help
- Supervisor Mode Access Prevention (SMAP) is a security
- feature in newer Intel processors. There is a small
- performance cost if this enabled and turned on; there is
- also a small increase in the kernel size if this is enabled.
-
- If unsure, say Y.
-
config X86_UMIP
def_bool y
prompt "User Mode Instruction Prevention" if EXPERT
diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 1261842d006c..66d3e3b1d24d 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -34,14 +34,17 @@ enum cpuid_leafs
CPUID_8000_001F_EAX,
};
+#define X86_CAP_FMT_NUM "%d:%d"
+#define x86_cap_flag_num(flag) ((flag) >> 5), ((flag) & 31)
+
#ifdef CONFIG_X86_FEATURE_NAMES
extern const char * const x86_cap_flags[NCAPINTS*32];
extern const char * const x86_power_flags[32];
#define X86_CAP_FMT "%s"
#define x86_cap_flag(flag) x86_cap_flags[flag]
#else
-#define X86_CAP_FMT "%d:%d"
-#define x86_cap_flag(flag) ((flag) >> 5), ((flag) & 31)
+#define X86_CAP_FMT X86_CAP_FMT_NUM
+#define x86_cap_flag x86_cap_flag_num
#endif
/*
diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h
index b37de8268c9a..36369e76cc63 100644
--- a/arch/x86/include/asm/disabled-features.h
+++ b/arch/x86/include/asm/disabled-features.h
@@ -10,12 +10,6 @@
* cpu_feature_enabled().
*/
-#ifdef CONFIG_X86_SMAP
-# define DISABLE_SMAP 0
-#else
-# define DISABLE_SMAP (1<<(X86_FEATURE_SMAP & 31))
-#endif
-
#ifdef CONFIG_X86_UMIP
# define DISABLE_UMIP 0
#else
@@ -86,7 +80,7 @@
#define DISABLED_MASK6 0
#define DISABLED_MASK7 (DISABLE_PTI)
#define DISABLED_MASK8 (DISABLE_TDX_GUEST)
-#define DISABLED_MASK9 (DISABLE_SMAP|DISABLE_SGX)
+#define DISABLED_MASK9 (DISABLE_SGX)
#define DISABLED_MASK10 0
#define DISABLED_MASK11 0
#define DISABLED_MASK12 0
diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index f042cfc9938f..647d71535ce3 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -39,7 +39,6 @@ void xen_entry_INT80_compat(void);
#endif
void x86_configure_nx(void);
-void x86_report_nx(void);
extern int reboot_force;
diff --git a/arch/x86/include/asm/smap.h b/arch/x86/include/asm/smap.h
index d17b39893b79..bab490379c65 100644
--- a/arch/x86/include/asm/smap.h
+++ b/arch/x86/include/asm/smap.h
@@ -19,25 +19,14 @@
#ifdef __ASSEMBLY__
-#ifdef CONFIG_X86_SMAP
-
#define ASM_CLAC \
ALTERNATIVE "", __ASM_CLAC, X86_FEATURE_SMAP
#define ASM_STAC \
ALTERNATIVE "", __ASM_STAC, X86_FEATURE_SMAP
-#else /* CONFIG_X86_SMAP */
-
-#define ASM_CLAC
-#define ASM_STAC
-
-#endif /* CONFIG_X86_SMAP */
-
#else /* __ASSEMBLY__ */
-#ifdef CONFIG_X86_SMAP
-
static __always_inline void clac(void)
{
/* Note: a barrier is implicit in alternative() */
@@ -76,19 +65,6 @@ static __always_inline void smap_restore(unsigned long flags)
#define ASM_STAC \
ALTERNATIVE("", __ASM_STAC, X86_FEATURE_SMAP)
-#else /* CONFIG_X86_SMAP */
-
-static inline void clac(void) { }
-static inline void stac(void) { }
-
-static inline unsigned long smap_save(void) { return 0; }
-static inline void smap_restore(unsigned long flags) { }
-
-#define ASM_CLAC
-#define ASM_STAC
-
-#endif /* CONFIG_X86_SMAP */
-
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_SMAP_H */
diff --git a/arch/x86/include/asm/suspend_32.h b/arch/x86/include/asm/suspend_32.h
index 7b132d0312eb..a800abb1a992 100644
--- a/arch/x86/include/asm/suspend_32.h
+++ b/arch/x86/include/asm/suspend_32.h
@@ -19,7 +19,6 @@ struct saved_context {
u16 gs;
unsigned long cr0, cr2, cr3, cr4;
u64 misc_enable;
- bool misc_enable_saved;
struct saved_msrs saved_msrs;
struct desc_ptr gdt_desc;
struct desc_ptr idt;
@@ -28,6 +27,7 @@ struct saved_context {
unsigned long tr;
unsigned long safety;
unsigned long return_address;
+ bool misc_enable_saved;
} __attribute__((packed));
/* routines for saving/restoring kernel state */
diff --git a/arch/x86/include/asm/suspend_64.h b/arch/x86/include/asm/suspend_64.h
index 35bb35d28733..54df06687d83 100644
--- a/arch/x86/include/asm/suspend_64.h
+++ b/arch/x86/include/asm/suspend_64.h
@@ -14,9 +14,13 @@
* Image of the saved processor state, used by the low level ACPI suspend to
* RAM code and by the low level hibernation code.
*
- * If you modify it, fix arch/x86/kernel/acpi/wakeup_64.S and make sure that
- * __save/__restore_processor_state(), defined in arch/x86/kernel/suspend_64.c,
- * still work as required.
+ * If you modify it, check how it is used in arch/x86/kernel/acpi/wakeup_64.S
+ * and make sure that __save/__restore_processor_state(), defined in
+ * arch/x86/power/cpu.c, still work as required.
+ *
+ * Because the structure is packed, make sure to avoid unaligned members. For
+ * optimisation purposes but also because tools like kmemleak only search for
+ * pointers that are aligned.
*/
struct saved_context {
struct pt_regs regs;
@@ -36,7 +40,6 @@ struct saved_context {
unsigned long cr0, cr2, cr3, cr4;
u64 misc_enable;
- bool misc_enable_saved;
struct saved_msrs saved_msrs;
unsigned long efer;
u16 gdt_pad; /* Unused */
@@ -48,6 +51,7 @@ struct saved_context {
unsigned long tr;
unsigned long safety;
unsigned long return_address;
+ bool misc_enable_saved;
} __attribute__((packed));
#define loaddebug(thread,register) \
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 6296e1ebed1d..d879a6c93609 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -446,6 +446,13 @@ void update_srbds_msr(void)
if (srbds_mitigation == SRBDS_MITIGATION_UCODE_NEEDED)
return;
+ /*
+ * A MDS_NO CPU for which SRBDS mitigation is not needed due to TSX
+ * being disabled and it hasn't received the SRBDS MSR microcode.
+ */
+ if (!boot_cpu_has(X86_FEATURE_SRBDS_CTRL))
+ return;
+
rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
switch (srbds_mitigation) {
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index f0baf1b7522e..2e9142797c99 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -299,13 +299,6 @@ static int __init cachesize_setup(char *str)
}
__setup("cachesize=", cachesize_setup);
-static int __init x86_sep_setup(char *s)
-{
- setup_clear_cpu_cap(X86_FEATURE_SEP);
- return 1;
-}
-__setup("nosep", x86_sep_setup);
-
/* Standard macro to see if a specific flag is changeable */
static inline int flag_is_changeable_p(u32 flag)
{
@@ -377,26 +370,12 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
}
#endif
-static __init int setup_disable_smep(char *arg)
-{
- setup_clear_cpu_cap(X86_FEATURE_SMEP);
- return 1;
-}
-__setup("nosmep", setup_disable_smep);
-
static __always_inline void setup_smep(struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_SMEP))
cr4_set_bits(X86_CR4_SMEP);
}
-static __init int setup_disable_smap(char *arg)
-{
- setup_clear_cpu_cap(X86_FEATURE_SMAP);
- return 1;
-}
-__setup("nosmap", setup_disable_smap);
-
static __always_inline void setup_smap(struct cpuinfo_x86 *c)
{
unsigned long eflags = native_save_fl();
@@ -404,14 +383,8 @@ static __always_inline void setup_smap(struct cpuinfo_x86 *c)
/* This should have been cleared long ago */
BUG_ON(eflags & X86_EFLAGS_AC);
- if (cpu_has(c, X86_FEATURE_SMAP)) {
-#ifdef CONFIG_X86_SMAP
+ if (cpu_has(c, X86_FEATURE_SMAP))
cr4_set_bits(X86_CR4_SMAP);
-#else
- clear_cpu_cap(c, X86_FEATURE_SMAP);
- cr4_clear_bits(X86_CR4_SMAP);
-#endif
- }
}
static __always_inline void setup_umip(struct cpuinfo_x86 *c)
@@ -1369,8 +1342,8 @@ static void detect_nopl(void)
static void __init cpu_parse_early_param(void)
{
char arg[128];
- char *argptr = arg;
- int arglen, res, bit;
+ char *argptr = arg, *opt;
+ int arglen, taint = 0;
#ifdef CONFIG_X86_32
if (cmdline_find_option_bool(boot_command_line, "no387"))
@@ -1398,21 +1371,61 @@ static void __init cpu_parse_early_param(void)
return;
pr_info("Clearing CPUID bits:");
- do {
- res = get_option(&argptr, &bit);
- if (res == 0 || res == 3)
- break;
- /* If the argument was too long, the last bit may be cut off */
- if (res == 1 && arglen >= sizeof(arg))
- break;
+ while (argptr) {
+ bool found __maybe_unused = false;
+ unsigned int bit;
- if (bit >= 0 && bit < NCAPINTS * 32) {
- pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit));
+ opt = strsep(&argptr, ",");
+
+ /*
+ * Handle naked numbers first for feature flags which don't
+ * have names.
+ */
+ if (!kstrtouint(opt, 10, &bit)) {
+ if (bit < NCAPINTS * 32) {
+
+#ifdef CONFIG_X86_FEATURE_NAMES
+ /* empty-string, i.e., ""-defined feature flags */
+ if (!x86_cap_flags[bit])
+ pr_cont(" " X86_CAP_FMT_NUM, x86_cap_flag_num(bit));
+ else
+#endif
+ pr_cont(" " X86_CAP_FMT, x86_cap_flag(bit));
+
+ setup_clear_cpu_cap(bit);
+ taint++;
+ }
+ /*
+ * The assumption is that there are no feature names with only
+ * numbers in the name thus go to the next argument.
+ */
+ continue;
+ }
+
+#ifdef CONFIG_X86_FEATURE_NAMES
+ for (bit = 0; bit < 32 * NCAPINTS; bit++) {
+ if (!x86_cap_flag(bit))
+ continue;
+
+ if (strcmp(x86_cap_flag(bit), opt))
+ continue;
+
+ pr_cont(" %s", opt);
setup_clear_cpu_cap(bit);
+ taint++;
+ found = true;
+ break;
}
- } while (res == 2);
+
+ if (!found)
+ pr_cont(" (unknown: %s)", opt);
+#endif
+ }
pr_cont("\n");
+
+ if (taint)
+ add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
}
/*
@@ -1860,14 +1873,6 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c)
tsx_ap_init();
}
-static __init int setup_noclflush(char *arg)
-{
- setup_clear_cpu_cap(X86_FEATURE_CLFLUSH);
- setup_clear_cpu_cap(X86_FEATURE_CLFLUSHOPT);
- return 1;
-}
-__setup("noclflush", setup_noclflush);
-
void print_cpu_info(struct cpuinfo_x86 *c)
{
const char *vendor = NULL;
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index c95b9ac5a457..249981bf3d8a 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -756,6 +756,30 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
return 0;
}
+void x86_configure_nx(void)
+{
+ if (boot_cpu_has(X86_FEATURE_NX))
+ __supported_pte_mask |= _PAGE_NX;
+ else
+ __supported_pte_mask &= ~_PAGE_NX;
+}
+
+static void __init x86_report_nx(void)
+{
+ if (!boot_cpu_has(X86_FEATURE_NX)) {
+ printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
+ "missing in CPU!\n");
+ } else {
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+ printk(KERN_INFO "NX (Execute Disable) protection: active\n");
+#else
+ /* 32bit non-PAE kernel, NX cannot be used */
+ printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
+ "cannot be enabled: non-PAE kernel!\n");
+#endif
+ }
+}
+
/*
* Determine if we were loaded by an EFI loader. If so, then we have also been
* passed the efi memmap, systab, etc., so we should use these data structures
@@ -896,9 +920,7 @@ void __init setup_arch(char **cmdline_p)
/*
* x86_configure_nx() is called before parse_early_param() to detect
* whether hardware doesn't support NX (so that the early EHCI debug
- * console setup can safely call set_fixmap()). It may then be called
- * again from within noexec_setup() during parsing early parameters
- * to honor the respective command line option.
+ * console setup can safely call set_fixmap()).
*/
x86_configure_nx();
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile
index fe3d3061fc11..d957dc15b371 100644
--- a/arch/x86/mm/Makefile
+++ b/arch/x86/mm/Makefile
@@ -20,13 +20,12 @@ CFLAGS_REMOVE_mem_encrypt_identity.o = -pg
endif
obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o mmap.o \
- pgtable.o physaddr.o setup_nx.o tlb.o cpu_entry_area.o maccess.o
+ pgtable.o physaddr.o tlb.o cpu_entry_area.o maccess.o
obj-y += pat/
# Make sure __phys_addr has no stackprotector
CFLAGS_physaddr.o := -fno-stack-protector
-CFLAGS_setup_nx.o := -fno-stack-protector
CFLAGS_mem_encrypt_identity.o := -fno-stack-protector
CFLAGS_fault.o := -I $(srctree)/$(src)/../include/asm/trace
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index e2942335d143..61d0ab154f96 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -110,7 +110,6 @@ int force_personality32;
/*
* noexec32=on|off
* Control non executable heap for 32bit processes.
- * To control the stack too use noexec=off
*
* on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
* off PROT_READ implies PROT_EXEC
diff --git a/arch/x86/mm/setup_nx.c b/arch/x86/mm/setup_nx.c
deleted file mode 100644
index ed5667f5169f..000000000000
--- a/arch/x86/mm/setup_nx.c
+++ /dev/null
@@ -1,62 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <linux/spinlock.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/pgtable.h>
-
-#include <asm/proto.h>
-#include <asm/cpufeature.h>
-
-static int disable_nx;
-
-/*
- * noexec = on|off
- *
- * Control non-executable mappings for processes.
- *
- * on Enable
- * off Disable
- */
-static int __init noexec_setup(char *str)
-{
- if (!str)
- return -EINVAL;
- if (!strncmp(str, "on", 2)) {
- disable_nx = 0;
- } else if (!strncmp(str, "off", 3)) {
- disable_nx = 1;
- }
- x86_configure_nx();
- return 0;
-}
-early_param("noexec", noexec_setup);
-
-void x86_configure_nx(void)
-{
- if (boot_cpu_has(X86_FEATURE_NX) && !disable_nx)
- __supported_pte_mask |= _PAGE_NX;
- else
- __supported_pte_mask &= ~_PAGE_NX;
-}
-
-void __init x86_report_nx(void)
-{
- if (!boot_cpu_has(X86_FEATURE_NX)) {
- printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
- "missing in CPU!\n");
- } else {
-#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
- if (disable_nx) {
- printk(KERN_INFO "NX (Execute Disable) protection: "
- "disabled by kernel command line option\n");
- } else {
- printk(KERN_INFO "NX (Execute Disable) protection: "
- "active\n");
- }
-#else
- /* 32bit non-PAE kernel, NX cannot be used */
- printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
- "cannot be enabled: non-PAE kernel!\n");
-#endif
- }
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 07:38:36 +0000