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-rw-r--r--arch/x86/kernel/acpi/sleep.c15
-rw-r--r--arch/x86/kernel/cpu/common.c44
-rw-r--r--arch/x86/kernel/entry_32.S26
-rw-r--r--arch/x86/kernel/entry_64.S11
-rw-r--r--arch/x86/kernel/head_32.S31
-rw-r--r--arch/x86/kernel/signal.c24
-rw-r--r--arch/x86/kernel/xsave.c6
7 files changed, 108 insertions, 49 deletions
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
index 1b8e5a0..11676cf 100644
--- a/arch/x86/kernel/acpi/sleep.c
+++ b/arch/x86/kernel/acpi/sleep.c
@@ -43,17 +43,22 @@ int acpi_suspend_lowlevel(void)
header->video_mode = saved_video_mode;
+ header->pmode_behavior = 0;
+
#ifndef CONFIG_64BIT
store_gdt((struct desc_ptr *)&header->pmode_gdt);
- if (rdmsr_safe(MSR_EFER, &header->pmode_efer_low,
- &header->pmode_efer_high))
- header->pmode_efer_low = header->pmode_efer_high = 0;
+ if (!rdmsr_safe(MSR_EFER,
+ &header->pmode_efer_low,
+ &header->pmode_efer_high))
+ header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
#endif /* !CONFIG_64BIT */
header->pmode_cr0 = read_cr0();
- header->pmode_cr4 = read_cr4_safe();
- header->pmode_behavior = 0;
+ if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
+ header->pmode_cr4 = read_cr4();
+ header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
+ }
if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
&header->pmode_misc_en_low,
&header->pmode_misc_en_high))
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 532691b..7505f7b 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -259,23 +259,36 @@ static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
}
#endif
-static int disable_smep __cpuinitdata;
static __init int setup_disable_smep(char *arg)
{
- disable_smep = 1;
+ setup_clear_cpu_cap(X86_FEATURE_SMEP);
return 1;
}
__setup("nosmep", setup_disable_smep);
-static __cpuinit void setup_smep(struct cpuinfo_x86 *c)
+static __always_inline void setup_smep(struct cpuinfo_x86 *c)
{
- if (cpu_has(c, X86_FEATURE_SMEP)) {
- if (unlikely(disable_smep)) {
- setup_clear_cpu_cap(X86_FEATURE_SMEP);
- clear_in_cr4(X86_CR4_SMEP);
- } else
- set_in_cr4(X86_CR4_SMEP);
- }
+ if (cpu_has(c, X86_FEATURE_SMEP))
+ set_in_cr4(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;
+
+ /* This should have been cleared long ago */
+ raw_local_save_flags(eflags);
+ BUG_ON(eflags & X86_EFLAGS_AC);
+
+ if (cpu_has(c, X86_FEATURE_SMAP))
+ set_in_cr4(X86_CR4_SMAP);
}
/*
@@ -712,8 +725,6 @@ static void __init early_identify_cpu(struct cpuinfo_x86 *c)
c->cpu_index = 0;
filter_cpuid_features(c, false);
- setup_smep(c);
-
if (this_cpu->c_bsp_init)
this_cpu->c_bsp_init(c);
}
@@ -798,8 +809,6 @@ static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
c->phys_proc_id = c->initial_apicid;
}
- setup_smep(c);
-
get_model_name(c); /* Default name */
detect_nopl(c);
@@ -864,6 +873,10 @@ static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
/* Disable the PN if appropriate */
squash_the_stupid_serial_number(c);
+ /* Set up SMEP/SMAP */
+ setup_smep(c);
+ setup_smap(c);
+
/*
* The vendor-specific functions might have changed features.
* Now we do "generic changes."
@@ -1114,7 +1127,8 @@ void syscall_init(void)
/* Flags to clear on syscall */
wrmsrl(MSR_SYSCALL_MASK,
- X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
+ X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
+ X86_EFLAGS_IOPL|X86_EFLAGS_AC);
}
/*
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index f438a44..0750e3b 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -57,6 +57,7 @@
#include <asm/cpufeature.h>
#include <asm/alternative-asm.h>
#include <asm/asm.h>
+#include <asm/smap.h>
/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
#include <linux/elf-em.h>
@@ -407,7 +408,9 @@ sysenter_past_esp:
*/
cmpl $__PAGE_OFFSET-3,%ebp
jae syscall_fault
+ ASM_STAC
1: movl (%ebp),%ebp
+ ASM_CLAC
movl %ebp,PT_EBP(%esp)
_ASM_EXTABLE(1b,syscall_fault)
@@ -488,6 +491,7 @@ ENDPROC(ia32_sysenter_target)
# system call handler stub
ENTRY(system_call)
RING0_INT_FRAME # can't unwind into user space anyway
+ ASM_CLAC
pushl_cfi %eax # save orig_eax
SAVE_ALL
GET_THREAD_INFO(%ebp)
@@ -670,6 +674,7 @@ END(syscall_exit_work)
RING0_INT_FRAME # can't unwind into user space anyway
syscall_fault:
+ ASM_CLAC
GET_THREAD_INFO(%ebp)
movl $-EFAULT,PT_EAX(%esp)
jmp resume_userspace
@@ -825,6 +830,7 @@ END(interrupt)
*/
.p2align CONFIG_X86_L1_CACHE_SHIFT
common_interrupt:
+ ASM_CLAC
addl $-0x80,(%esp) /* Adjust vector into the [-256,-1] range */
SAVE_ALL
TRACE_IRQS_OFF
@@ -841,6 +847,7 @@ ENDPROC(common_interrupt)
#define BUILD_INTERRUPT3(name, nr, fn) \
ENTRY(name) \
RING0_INT_FRAME; \
+ ASM_CLAC; \
pushl_cfi $~(nr); \
SAVE_ALL; \
TRACE_IRQS_OFF \
@@ -857,6 +864,7 @@ ENDPROC(name)
ENTRY(coprocessor_error)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_coprocessor_error
jmp error_code
@@ -865,6 +873,7 @@ END(coprocessor_error)
ENTRY(simd_coprocessor_error)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
#ifdef CONFIG_X86_INVD_BUG
/* AMD 486 bug: invd from userspace calls exception 19 instead of #GP */
@@ -886,6 +895,7 @@ END(simd_coprocessor_error)
ENTRY(device_not_available)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $-1 # mark this as an int
pushl_cfi $do_device_not_available
jmp error_code
@@ -906,6 +916,7 @@ END(native_irq_enable_sysexit)
ENTRY(overflow)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_overflow
jmp error_code
@@ -914,6 +925,7 @@ END(overflow)
ENTRY(bounds)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_bounds
jmp error_code
@@ -922,6 +934,7 @@ END(bounds)
ENTRY(invalid_op)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_invalid_op
jmp error_code
@@ -930,6 +943,7 @@ END(invalid_op)
ENTRY(coprocessor_segment_overrun)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_coprocessor_segment_overrun
jmp error_code
@@ -938,6 +952,7 @@ END(coprocessor_segment_overrun)
ENTRY(invalid_TSS)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_invalid_TSS
jmp error_code
CFI_ENDPROC
@@ -945,6 +960,7 @@ END(invalid_TSS)
ENTRY(segment_not_present)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_segment_not_present
jmp error_code
CFI_ENDPROC
@@ -952,6 +968,7 @@ END(segment_not_present)
ENTRY(stack_segment)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_stack_segment
jmp error_code
CFI_ENDPROC
@@ -959,6 +976,7 @@ END(stack_segment)
ENTRY(alignment_check)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_alignment_check
jmp error_code
CFI_ENDPROC
@@ -966,6 +984,7 @@ END(alignment_check)
ENTRY(divide_error)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0 # no error code
pushl_cfi $do_divide_error
jmp error_code
@@ -975,6 +994,7 @@ END(divide_error)
#ifdef CONFIG_X86_MCE
ENTRY(machine_check)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi machine_check_vector
jmp error_code
@@ -984,6 +1004,7 @@ END(machine_check)
ENTRY(spurious_interrupt_bug)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $0
pushl_cfi $do_spurious_interrupt_bug
jmp error_code
@@ -1273,6 +1294,7 @@ return_to_handler:
ENTRY(page_fault)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_page_fault
ALIGN
error_code:
@@ -1345,6 +1367,7 @@ END(page_fault)
ENTRY(debug)
RING0_INT_FRAME
+ ASM_CLAC
cmpl $ia32_sysenter_target,(%esp)
jne debug_stack_correct
FIX_STACK 12, debug_stack_correct, debug_esp_fix_insn
@@ -1369,6 +1392,7 @@ END(debug)
*/
ENTRY(nmi)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi %eax
movl %ss, %eax
cmpw $__ESPFIX_SS, %ax
@@ -1439,6 +1463,7 @@ END(nmi)
ENTRY(int3)
RING0_INT_FRAME
+ ASM_CLAC
pushl_cfi $-1 # mark this as an int
SAVE_ALL
TRACE_IRQS_OFF
@@ -1459,6 +1484,7 @@ END(general_protection)
#ifdef CONFIG_KVM_GUEST
ENTRY(async_page_fault)
RING0_EC_FRAME
+ ASM_CLAC
pushl_cfi $do_async_page_fault
jmp error_code
CFI_ENDPROC
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 066334b..44531ac 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -57,6 +57,7 @@
#include <asm/percpu.h>
#include <asm/asm.h>
#include <asm/rcu.h>
+#include <asm/smap.h>
#include <linux/err.h>
/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
@@ -568,7 +569,8 @@ END(ret_from_fork)
* System call entry. Up to 6 arguments in registers are supported.
*
* SYSCALL does not save anything on the stack and does not change the
- * stack pointer.
+ * stack pointer. However, it does mask the flags register for us, so
+ * CLD and CLAC are not needed.
*/
/*
@@ -987,6 +989,7 @@ END(interrupt)
*/
.p2align CONFIG_X86_L1_CACHE_SHIFT
common_interrupt:
+ ASM_CLAC
XCPT_FRAME
addq $-0x80,(%rsp) /* Adjust vector to [-256,-1] range */
interrupt do_IRQ
@@ -1126,6 +1129,7 @@ END(common_interrupt)
*/
.macro apicinterrupt num sym do_sym
ENTRY(\sym)
+ ASM_CLAC
INTR_FRAME
pushq_cfi $~(\num)
.Lcommon_\sym:
@@ -1180,6 +1184,7 @@ apicinterrupt IRQ_WORK_VECTOR \
*/
.macro zeroentry sym do_sym
ENTRY(\sym)
+ ASM_CLAC
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */
@@ -1197,6 +1202,7 @@ END(\sym)
.macro paranoidzeroentry sym do_sym
ENTRY(\sym)
+ ASM_CLAC
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */
@@ -1215,6 +1221,7 @@ END(\sym)
#define INIT_TSS_IST(x) PER_CPU_VAR(init_tss) + (TSS_ist + ((x) - 1) * 8)
.macro paranoidzeroentry_ist sym do_sym ist
ENTRY(\sym)
+ ASM_CLAC
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
pushq_cfi $-1 /* ORIG_RAX: no syscall to restart */
@@ -1234,6 +1241,7 @@ END(\sym)
.macro errorentry sym do_sym
ENTRY(\sym)
+ ASM_CLAC
XCPT_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
subq $ORIG_RAX-R15, %rsp
@@ -1252,6 +1260,7 @@ END(\sym)
/* error code is on the stack already */
.macro paranoiderrorentry sym do_sym
ENTRY(\sym)
+ ASM_CLAC
XCPT_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
subq $ORIG_RAX-R15, %rsp
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index d42ab17..957a47a 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -287,27 +287,28 @@ ENTRY(startup_32_smp)
leal -__PAGE_OFFSET(%ecx),%esp
default_entry:
-
/*
* New page tables may be in 4Mbyte page mode and may
* be using the global pages.
*
* NOTE! If we are on a 486 we may have no cr4 at all!
- * So we do not try to touch it unless we really have
- * some bits in it to set. This won't work if the BSP
- * implements cr4 but this AP does not -- very unlikely
- * but be warned! The same applies to the pse feature
- * if not equally supported. --macro
- *
- * NOTE! We have to correct for the fact that we're
- * not yet offset PAGE_OFFSET..
+ * Specifically, cr4 exists if and only if CPUID exists,
+ * which in turn exists if and only if EFLAGS.ID exists.
*/
-#define cr4_bits pa(mmu_cr4_features)
- movl cr4_bits,%edx
- andl %edx,%edx
- jz 6f
- movl %cr4,%eax # Turn on paging options (PSE,PAE,..)
- orl %edx,%eax
+ movl $X86_EFLAGS_ID,%ecx
+ pushl %ecx
+ popfl
+ pushfl
+ popl %eax
+ pushl $0
+ popfl
+ pushfl
+ popl %edx
+ xorl %edx,%eax
+ testl %ecx,%eax
+ jz 6f # No ID flag = no CPUID = no CR4
+
+ movl pa(mmu_cr4_features),%eax
movl %eax,%cr4
testb $X86_CR4_PAE, %al # check if PAE is enabled
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 3160c26..b33144c 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -114,11 +114,12 @@ int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
regs->orig_ax = -1; /* disable syscall checks */
get_user_ex(buf, &sc->fpstate);
- err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32));
get_user_ex(*pax, &sc->ax);
} get_user_catch(err);
+ err |= restore_xstate_sig(buf, config_enabled(CONFIG_X86_32));
+
return err;
}
@@ -355,7 +356,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
put_user_ex(sig, &frame->sig);
put_user_ex(&frame->info, &frame->pinfo);
put_user_ex(&frame->uc, &frame->puc);
- err |= copy_siginfo_to_user(&frame->info, info);
/* Create the ucontext. */
if (cpu_has_xsave)
@@ -367,9 +367,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
put_user_ex(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
- regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
/* Set up to return from userspace. */
restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
@@ -386,6 +383,11 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
*/
put_user_ex(*((u64 *)&rt_retcode), (u64 *)frame->retcode);
} put_user_catch(err);
+
+ err |= copy_siginfo_to_user(&frame->info, info);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
+ regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
return -EFAULT;
@@ -434,8 +436,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
put_user_ex(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
put_user_ex(me->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
/* Set up to return from userspace. If provided, use a stub
already in userspace. */
@@ -448,6 +448,9 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
}
} put_user_catch(err);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fp, regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
if (err)
return -EFAULT;
@@ -504,9 +507,6 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
&frame->uc.uc_stack.ss_flags);
put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
put_user_ex(0, &frame->uc.uc__pad0);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
- regs, set->sig[0]);
- err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (ka->sa.sa_flags & SA_RESTORER) {
restorer = ka->sa.sa_restorer;
@@ -518,6 +518,10 @@ static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
put_user_ex(restorer, &frame->pretcode);
} put_user_catch(err);
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
+ regs, set->sig[0]);
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
if (err)
return -EFAULT;
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index 4e89b3d..ada87a3 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -315,7 +315,7 @@ static inline int restore_user_xstate(void __user *buf, u64 xbv, int fx_only)
if ((unsigned long)buf % 64 || fx_only) {
u64 init_bv = pcntxt_mask & ~XSTATE_FPSSE;
xrstor_state(init_xstate_buf, init_bv);
- return fxrstor_checking((__force void *) buf);
+ return fxrstor_user(buf);
} else {
u64 init_bv = pcntxt_mask & ~xbv;
if (unlikely(init_bv))
@@ -323,9 +323,9 @@ static inline int restore_user_xstate(void __user *buf, u64 xbv, int fx_only)
return xrestore_user(buf, xbv);
}
} else if (use_fxsr()) {
- return fxrstor_checking((__force void *) buf);
+ return fxrstor_user(buf);
} else
- return frstor_checking((__force void *) buf);
+ return frstor_user(buf);
}
int __restore_xstate_sig(void __user *buf, void __user *buf_fx, int size)
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