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-rw-r--r--arch/x86/include/asm/alternative.h4
-rw-r--r--arch/x86/include/asm/cpufeatures.h18
-rw-r--r--arch/x86/include/asm/kvm_host.h2
-rw-r--r--arch/x86/include/asm/mmu_context.h2
-rw-r--r--arch/x86/include/asm/msr-index.h9
-rw-r--r--arch/x86/include/asm/nospec-branch.h43
-rw-r--r--arch/x86/include/asm/pkeys.h18
-rw-r--r--arch/x86/include/asm/spec-ctrl.h80
-rw-r--r--arch/x86/include/asm/thread_info.h4
-rw-r--r--arch/x86/include/asm/tlbflush.h7
10 files changed, 159 insertions, 28 deletions
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index cf5961ca8677..4cd6a3b71824 100644
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -218,13 +218,11 @@ static inline int alternatives_text_reserved(void *start, void *end)
*/
#define alternative_call_2(oldfunc, newfunc1, feature1, newfunc2, feature2, \
output, input...) \
-{ \
asm volatile (ALTERNATIVE_2("call %P[old]", "call %P[new1]", feature1,\
"call %P[new2]", feature2) \
: output, ASM_CALL_CONSTRAINT \
: [old] "i" (oldfunc), [new1] "i" (newfunc1), \
- [new2] "i" (newfunc2), ## input); \
-}
+ [new2] "i" (newfunc2), ## input)
/*
* use this macro(s) if you need more than one output parameter
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 23a65439c37c..403e97d5e243 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -198,7 +198,6 @@
#define X86_FEATURE_CAT_L2 ( 7*32+ 5) /* Cache Allocation Technology L2 */
#define X86_FEATURE_CDP_L3 ( 7*32+ 6) /* Code and Data Prioritization L3 */
#define X86_FEATURE_INVPCID_SINGLE ( 7*32+ 7) /* Effectively INVPCID && CR4.PCIDE=1 */
-
#define X86_FEATURE_HW_PSTATE ( 7*32+ 8) /* AMD HW-PState */
#define X86_FEATURE_PROC_FEEDBACK ( 7*32+ 9) /* AMD ProcFeedbackInterface */
#define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
@@ -207,11 +206,19 @@
#define X86_FEATURE_RETPOLINE_AMD ( 7*32+13) /* "" AMD Retpoline mitigation for Spectre variant 2 */
#define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
+#define X86_FEATURE_MSR_SPEC_CTRL ( 7*32+16) /* "" MSR SPEC_CTRL is implemented */
+#define X86_FEATURE_SSBD ( 7*32+17) /* Speculative Store Bypass Disable */
#define X86_FEATURE_MBA ( 7*32+18) /* Memory Bandwidth Allocation */
#define X86_FEATURE_RSB_CTXSW ( 7*32+19) /* "" Fill RSB on context switches */
#define X86_FEATURE_USE_IBPB ( 7*32+21) /* "" Indirect Branch Prediction Barrier enabled */
#define X86_FEATURE_USE_IBRS_FW ( 7*32+22) /* "" Use IBRS during runtime firmware calls */
+#define X86_FEATURE_SPEC_STORE_BYPASS_DISABLE ( 7*32+23) /* "" Disable Speculative Store Bypass. */
+#define X86_FEATURE_LS_CFG_SSBD ( 7*32+24) /* "" AMD SSBD implementation via LS_CFG MSR */
+#define X86_FEATURE_IBRS ( 7*32+25) /* Indirect Branch Restricted Speculation */
+#define X86_FEATURE_IBPB ( 7*32+26) /* Indirect Branch Prediction Barrier */
+#define X86_FEATURE_STIBP ( 7*32+27) /* Single Thread Indirect Branch Predictors */
+#define X86_FEATURE_ZEN ( 7*32+28) /* "" CPU is AMD family 0x17 (Zen) */
/* Virtualization flags: Linux defined, word 8 */
#define X86_FEATURE_TPR_SHADOW ( 8*32+ 0) /* Intel TPR Shadow */
@@ -272,9 +279,10 @@
#define X86_FEATURE_CLZERO (13*32+ 0) /* CLZERO instruction */
#define X86_FEATURE_IRPERF (13*32+ 1) /* Instructions Retired Count */
#define X86_FEATURE_XSAVEERPTR (13*32+ 2) /* Always save/restore FP error pointers */
-#define X86_FEATURE_IBPB (13*32+12) /* Indirect Branch Prediction Barrier */
-#define X86_FEATURE_IBRS (13*32+14) /* Indirect Branch Restricted Speculation */
-#define X86_FEATURE_STIBP (13*32+15) /* Single Thread Indirect Branch Predictors */
+#define X86_FEATURE_AMD_IBPB (13*32+12) /* "" Indirect Branch Prediction Barrier */
+#define X86_FEATURE_AMD_IBRS (13*32+14) /* "" Indirect Branch Restricted Speculation */
+#define X86_FEATURE_AMD_STIBP (13*32+15) /* "" Single Thread Indirect Branch Predictors */
+#define X86_FEATURE_VIRT_SSBD (13*32+25) /* Virtualized Speculative Store Bypass Disable */
/* Thermal and Power Management Leaf, CPUID level 0x00000006 (EAX), word 14 */
#define X86_FEATURE_DTHERM (14*32+ 0) /* Digital Thermal Sensor */
@@ -331,6 +339,7 @@
#define X86_FEATURE_SPEC_CTRL (18*32+26) /* "" Speculation Control (IBRS + IBPB) */
#define X86_FEATURE_INTEL_STIBP (18*32+27) /* "" Single Thread Indirect Branch Predictors */
#define X86_FEATURE_ARCH_CAPABILITIES (18*32+29) /* IA32_ARCH_CAPABILITIES MSR (Intel) */
+#define X86_FEATURE_SPEC_CTRL_SSBD (18*32+31) /* "" Speculative Store Bypass Disable */
/*
* BUG word(s)
@@ -360,5 +369,6 @@
#define X86_BUG_CPU_MELTDOWN X86_BUG(14) /* CPU is affected by meltdown attack and needs kernel page table isolation */
#define X86_BUG_SPECTRE_V1 X86_BUG(15) /* CPU is affected by Spectre variant 1 attack with conditional branches */
#define X86_BUG_SPECTRE_V2 X86_BUG(16) /* CPU is affected by Spectre variant 2 attack with indirect branches */
+#define X86_BUG_SPEC_STORE_BYPASS X86_BUG(17) /* CPU is affected by speculative store bypass attack */
#endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4f8b80199672..174b9c41efce 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -908,7 +908,7 @@ struct kvm_x86_ops {
int (*hardware_setup)(void); /* __init */
void (*hardware_unsetup)(void); /* __exit */
bool (*cpu_has_accelerated_tpr)(void);
- bool (*cpu_has_high_real_mode_segbase)(void);
+ bool (*has_emulated_msr)(int index);
void (*cpuid_update)(struct kvm_vcpu *vcpu);
int (*vm_init)(struct kvm *kvm);
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index 1de72ce514cd..ed97ef3b48a7 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -192,7 +192,7 @@ static inline int init_new_context(struct task_struct *tsk,
#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
if (cpu_feature_enabled(X86_FEATURE_OSPKE)) {
- /* pkey 0 is the default and always allocated */
+ /* pkey 0 is the default and allocated implicitly */
mm->context.pkey_allocation_map = 0x1;
/* -1 means unallocated or invalid */
mm->context.execute_only_pkey = -1;
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index eb83ff1bae8f..504b21692d32 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -42,6 +42,8 @@
#define MSR_IA32_SPEC_CTRL 0x00000048 /* Speculation Control */
#define SPEC_CTRL_IBRS (1 << 0) /* Indirect Branch Restricted Speculation */
#define SPEC_CTRL_STIBP (1 << 1) /* Single Thread Indirect Branch Predictors */
+#define SPEC_CTRL_SSBD_SHIFT 2 /* Speculative Store Bypass Disable bit */
+#define SPEC_CTRL_SSBD (1 << SPEC_CTRL_SSBD_SHIFT) /* Speculative Store Bypass Disable */
#define MSR_IA32_PRED_CMD 0x00000049 /* Prediction Command */
#define PRED_CMD_IBPB (1 << 0) /* Indirect Branch Prediction Barrier */
@@ -68,6 +70,11 @@
#define MSR_IA32_ARCH_CAPABILITIES 0x0000010a
#define ARCH_CAP_RDCL_NO (1 << 0) /* Not susceptible to Meltdown */
#define ARCH_CAP_IBRS_ALL (1 << 1) /* Enhanced IBRS support */
+#define ARCH_CAP_SSB_NO (1 << 4) /*
+ * Not susceptible to Speculative Store Bypass
+ * attack, so no Speculative Store Bypass
+ * control required.
+ */
#define MSR_IA32_BBL_CR_CTL 0x00000119
#define MSR_IA32_BBL_CR_CTL3 0x0000011e
@@ -337,6 +344,8 @@
#define MSR_AMD64_IBSOPDATA4 0xc001103d
#define MSR_AMD64_IBS_REG_COUNT_MAX 8 /* includes MSR_AMD64_IBSBRTARGET */
+#define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f
+
/* Fam 17h MSRs */
#define MSR_F17H_IRPERF 0xc00000e9
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index f928ad9b143f..8b38df98548e 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -217,6 +217,14 @@ enum spectre_v2_mitigation {
SPECTRE_V2_IBRS,
};
+/* The Speculative Store Bypass disable variants */
+enum ssb_mitigation {
+ SPEC_STORE_BYPASS_NONE,
+ SPEC_STORE_BYPASS_DISABLE,
+ SPEC_STORE_BYPASS_PRCTL,
+ SPEC_STORE_BYPASS_SECCOMP,
+};
+
extern char __indirect_thunk_start[];
extern char __indirect_thunk_end[];
@@ -241,22 +249,27 @@ static inline void vmexit_fill_RSB(void)
#endif
}
-#define alternative_msr_write(_msr, _val, _feature) \
- asm volatile(ALTERNATIVE("", \
- "movl %[msr], %%ecx\n\t" \
- "movl %[val], %%eax\n\t" \
- "movl $0, %%edx\n\t" \
- "wrmsr", \
- _feature) \
- : : [msr] "i" (_msr), [val] "i" (_val) \
- : "eax", "ecx", "edx", "memory")
+static __always_inline
+void alternative_msr_write(unsigned int msr, u64 val, unsigned int feature)
+{
+ asm volatile(ALTERNATIVE("", "wrmsr", %c[feature])
+ : : "c" (msr),
+ "a" ((u32)val),
+ "d" ((u32)(val >> 32)),
+ [feature] "i" (feature)
+ : "memory");
+}
static inline void indirect_branch_prediction_barrier(void)
{
- alternative_msr_write(MSR_IA32_PRED_CMD, PRED_CMD_IBPB,
- X86_FEATURE_USE_IBPB);
+ u64 val = PRED_CMD_IBPB;
+
+ alternative_msr_write(MSR_IA32_PRED_CMD, val, X86_FEATURE_USE_IBPB);
}
+/* The Intel SPEC CTRL MSR base value cache */
+extern u64 x86_spec_ctrl_base;
+
/*
* With retpoline, we must use IBRS to restrict branch prediction
* before calling into firmware.
@@ -265,14 +278,18 @@ static inline void indirect_branch_prediction_barrier(void)
*/
#define firmware_restrict_branch_speculation_start() \
do { \
+ u64 val = x86_spec_ctrl_base | SPEC_CTRL_IBRS; \
+ \
preempt_disable(); \
- alternative_msr_write(MSR_IA32_SPEC_CTRL, SPEC_CTRL_IBRS, \
+ alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \
X86_FEATURE_USE_IBRS_FW); \
} while (0)
#define firmware_restrict_branch_speculation_end() \
do { \
- alternative_msr_write(MSR_IA32_SPEC_CTRL, 0, \
+ u64 val = x86_spec_ctrl_base; \
+ \
+ alternative_msr_write(MSR_IA32_SPEC_CTRL, val, \
X86_FEATURE_USE_IBRS_FW); \
preempt_enable(); \
} while (0)
diff --git a/arch/x86/include/asm/pkeys.h b/arch/x86/include/asm/pkeys.h
index a0ba1ffda0df..851c04b7a092 100644
--- a/arch/x86/include/asm/pkeys.h
+++ b/arch/x86/include/asm/pkeys.h
@@ -2,6 +2,8 @@
#ifndef _ASM_X86_PKEYS_H
#define _ASM_X86_PKEYS_H
+#define ARCH_DEFAULT_PKEY 0
+
#define arch_max_pkey() (boot_cpu_has(X86_FEATURE_OSPKE) ? 16 : 1)
extern int arch_set_user_pkey_access(struct task_struct *tsk, int pkey,
@@ -15,7 +17,7 @@ extern int __execute_only_pkey(struct mm_struct *mm);
static inline int execute_only_pkey(struct mm_struct *mm)
{
if (!boot_cpu_has(X86_FEATURE_OSPKE))
- return 0;
+ return ARCH_DEFAULT_PKEY;
return __execute_only_pkey(mm);
}
@@ -49,13 +51,21 @@ bool mm_pkey_is_allocated(struct mm_struct *mm, int pkey)
{
/*
* "Allocated" pkeys are those that have been returned
- * from pkey_alloc(). pkey 0 is special, and never
- * returned from pkey_alloc().
+ * from pkey_alloc() or pkey 0 which is allocated
+ * implicitly when the mm is created.
*/
- if (pkey <= 0)
+ if (pkey < 0)
return false;
if (pkey >= arch_max_pkey())
return false;
+ /*
+ * The exec-only pkey is set in the allocation map, but
+ * is not available to any of the user interfaces like
+ * mprotect_pkey().
+ */
+ if (pkey == mm->context.execute_only_pkey)
+ return false;
+
return mm_pkey_allocation_map(mm) & (1U << pkey);
}
diff --git a/arch/x86/include/asm/spec-ctrl.h b/arch/x86/include/asm/spec-ctrl.h
new file mode 100644
index 000000000000..ae7c2c5cd7f0
--- /dev/null
+++ b/arch/x86/include/asm/spec-ctrl.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_SPECCTRL_H_
+#define _ASM_X86_SPECCTRL_H_
+
+#include <linux/thread_info.h>
+#include <asm/nospec-branch.h>
+
+/*
+ * On VMENTER we must preserve whatever view of the SPEC_CTRL MSR
+ * the guest has, while on VMEXIT we restore the host view. This
+ * would be easier if SPEC_CTRL were architecturally maskable or
+ * shadowable for guests but this is not (currently) the case.
+ * Takes the guest view of SPEC_CTRL MSR as a parameter and also
+ * the guest's version of VIRT_SPEC_CTRL, if emulated.
+ */
+extern void x86_virt_spec_ctrl(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl, bool guest);
+
+/**
+ * x86_spec_ctrl_set_guest - Set speculation control registers for the guest
+ * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ * (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_set_guest(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+ x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, true);
+}
+
+/**
+ * x86_spec_ctrl_restore_host - Restore host speculation control registers
+ * @guest_spec_ctrl: The guest content of MSR_SPEC_CTRL
+ * @guest_virt_spec_ctrl: The guest controlled bits of MSR_VIRT_SPEC_CTRL
+ * (may get translated to MSR_AMD64_LS_CFG bits)
+ *
+ * Avoids writing to the MSR if the content/bits are the same
+ */
+static inline
+void x86_spec_ctrl_restore_host(u64 guest_spec_ctrl, u64 guest_virt_spec_ctrl)
+{
+ x86_virt_spec_ctrl(guest_spec_ctrl, guest_virt_spec_ctrl, false);
+}
+
+/* AMD specific Speculative Store Bypass MSR data */
+extern u64 x86_amd_ls_cfg_base;
+extern u64 x86_amd_ls_cfg_ssbd_mask;
+
+static inline u64 ssbd_tif_to_spec_ctrl(u64 tifn)
+{
+ BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT);
+ return (tifn & _TIF_SSBD) >> (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT);
+}
+
+static inline unsigned long ssbd_spec_ctrl_to_tif(u64 spec_ctrl)
+{
+ BUILD_BUG_ON(TIF_SSBD < SPEC_CTRL_SSBD_SHIFT);
+ return (spec_ctrl & SPEC_CTRL_SSBD) << (TIF_SSBD - SPEC_CTRL_SSBD_SHIFT);
+}
+
+static inline u64 ssbd_tif_to_amd_ls_cfg(u64 tifn)
+{
+ return (tifn & _TIF_SSBD) ? x86_amd_ls_cfg_ssbd_mask : 0ULL;
+}
+
+#ifdef CONFIG_SMP
+extern void speculative_store_bypass_ht_init(void);
+#else
+static inline void speculative_store_bypass_ht_init(void) { }
+#endif
+
+extern void speculative_store_bypass_update(unsigned long tif);
+
+static inline void speculative_store_bypass_update_current(void)
+{
+ speculative_store_bypass_update(current_thread_info()->flags);
+}
+
+#endif
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index 0242d91734ee..b1c9129f64fc 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -88,6 +88,7 @@ struct thread_info {
#define TIF_SIGPENDING 2 /* signal pending */
#define TIF_NEED_RESCHED 3 /* rescheduling necessary */
#define TIF_SINGLESTEP 4 /* reenable singlestep on user return*/
+#define TIF_SSBD 5 /* Reduced data speculation */
#define TIF_SYSCALL_EMU 6 /* syscall emulation active */
#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
#define TIF_SECCOMP 8 /* secure computing */
@@ -115,6 +116,7 @@ struct thread_info {
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED)
#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
+#define _TIF_SSBD (1 << TIF_SSBD)
#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU)
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP (1 << TIF_SECCOMP)
@@ -155,7 +157,7 @@ struct thread_info {
/* flags to check in __switch_to() */
#define _TIF_WORK_CTXSW \
- (_TIF_IO_BITMAP|_TIF_NOCPUID|_TIF_NOTSC|_TIF_BLOCKSTEP)
+ (_TIF_IO_BITMAP|_TIF_NOCPUID|_TIF_NOTSC|_TIF_BLOCKSTEP|_TIF_SSBD)
#define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY)
#define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW)
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 704f31315dde..875ca99b82ee 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -131,7 +131,12 @@ static inline unsigned long build_cr3(pgd_t *pgd, u16 asid)
static inline unsigned long build_cr3_noflush(pgd_t *pgd, u16 asid)
{
VM_WARN_ON_ONCE(asid > MAX_ASID_AVAILABLE);
- VM_WARN_ON_ONCE(!this_cpu_has(X86_FEATURE_PCID));
+ /*
+ * Use boot_cpu_has() instead of this_cpu_has() as this function
+ * might be called during early boot. This should work even after
+ * boot because all CPU's the have same capabilities:
+ */
+ VM_WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_PCID));
return __sme_pa(pgd) | kern_pcid(asid) | CR3_NOFLUSH;
}