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-rw-r--r--arch/x86/include/asm/cpu.h12
-rw-r--r--arch/x86/include/asm/cpufeatures.h7
-rw-r--r--arch/x86/include/asm/debugreg.h19
-rw-r--r--arch/x86/include/asm/hw_irq.h12
-rw-r--r--arch/x86/include/asm/irqflags.h4
-rw-r--r--arch/x86/include/asm/kvm-x86-ops.h1
-rw-r--r--arch/x86/include/asm/kvm_host.h17
-rw-r--r--arch/x86/include/asm/mshyperv.h6
-rw-r--r--arch/x86/include/asm/msr-index.h2
-rw-r--r--arch/x86/include/asm/mwait.h28
-rw-r--r--arch/x86/include/asm/nospec-branch.h37
-rw-r--r--arch/x86/include/asm/tdx.h2
-rw-r--r--arch/x86/include/uapi/asm/debugreg.h21
13 files changed, 123 insertions, 45 deletions
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index aa30fd8cad7f..b6099456477c 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -69,4 +69,16 @@ int intel_microcode_sanity_check(void *mc, bool print_err, int hdr_type);
extern struct cpumask cpus_stop_mask;
+union zen_patch_rev {
+ struct {
+ __u32 rev : 8,
+ stepping : 4,
+ model : 4,
+ __reserved : 4,
+ ext_model : 4,
+ ext_fam : 8;
+ };
+ __u32 ucode_rev;
+};
+
#endif /* _ASM_X86_CPU_H */
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 308e7d97135c..98e72c1391f2 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -227,6 +227,7 @@
#define X86_FEATURE_FLEXPRIORITY ( 8*32+ 1) /* "flexpriority" Intel FlexPriority */
#define X86_FEATURE_EPT ( 8*32+ 2) /* "ept" Intel Extended Page Table */
#define X86_FEATURE_VPID ( 8*32+ 3) /* "vpid" Intel Virtual Processor ID */
+#define X86_FEATURE_COHERENCY_SFW_NO ( 8*32+ 4) /* SNP cache coherency software work around not needed */
#define X86_FEATURE_VMMCALL ( 8*32+15) /* "vmmcall" Prefer VMMCALL to VMCALL */
#define X86_FEATURE_XENPV ( 8*32+16) /* Xen paravirtual guest */
@@ -455,6 +456,7 @@
#define X86_FEATURE_NO_NESTED_DATA_BP (20*32+ 0) /* No Nested Data Breakpoints */
#define X86_FEATURE_WRMSR_XX_BASE_NS (20*32+ 1) /* WRMSR to {FS,GS,KERNEL_GS}_BASE is non-serializing */
#define X86_FEATURE_LFENCE_RDTSC (20*32+ 2) /* LFENCE always serializing / synchronizes RDTSC */
+#define X86_FEATURE_VERW_CLEAR (20*32+ 5) /* The memory form of VERW mitigates TSA */
#define X86_FEATURE_NULL_SEL_CLR_BASE (20*32+ 6) /* Null Selector Clears Base */
#define X86_FEATURE_AUTOIBRS (20*32+ 8) /* Automatic IBRS */
#define X86_FEATURE_NO_SMM_CTL_MSR (20*32+ 9) /* SMM_CTL MSR is not present */
@@ -477,6 +479,10 @@
#define X86_FEATURE_FAST_CPPC (21*32 + 5) /* AMD Fast CPPC */
#define X86_FEATURE_INDIRECT_THUNK_ITS (21*32 + 6) /* Use thunk for indirect branches in lower half of cacheline */
+#define X86_FEATURE_TSA_SQ_NO (21*32+11) /* AMD CPU not vulnerable to TSA-SQ */
+#define X86_FEATURE_TSA_L1_NO (21*32+12) /* AMD CPU not vulnerable to TSA-L1 */
+#define X86_FEATURE_CLEAR_CPU_BUF_VM (21*32+13) /* Clear CPU buffers using VERW before VMRUN */
+
/*
* BUG word(s)
*/
@@ -529,4 +535,5 @@
#define X86_BUG_IBPB_NO_RET X86_BUG(1*32 + 4) /* "ibpb_no_ret" IBPB omits return target predictions */
#define X86_BUG_ITS X86_BUG(1*32 + 5) /* "its" CPU is affected by Indirect Target Selection */
#define X86_BUG_ITS_NATIVE_ONLY X86_BUG(1*32 + 6) /* "its_native_only" CPU is affected by ITS, VMX is not affected */
+#define X86_BUG_TSA X86_BUG( 1*32+ 9) /* "tsa" CPU is affected by Transient Scheduler Attacks */
#endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/debugreg.h b/arch/x86/include/asm/debugreg.h
index fdbbbfec745a..820b4aeabd0c 100644
--- a/arch/x86/include/asm/debugreg.h
+++ b/arch/x86/include/asm/debugreg.h
@@ -9,6 +9,14 @@
#include <asm/cpufeature.h>
#include <asm/msr.h>
+/*
+ * Define bits that are always set to 1 in DR7, only bit 10 is
+ * architecturally reserved to '1'.
+ *
+ * This is also the init/reset value for DR7.
+ */
+#define DR7_FIXED_1 0x00000400
+
DECLARE_PER_CPU(unsigned long, cpu_dr7);
#ifndef CONFIG_PARAVIRT_XXL
@@ -100,8 +108,8 @@ static __always_inline void native_set_debugreg(int regno, unsigned long value)
static inline void hw_breakpoint_disable(void)
{
- /* Zero the control register for HW Breakpoint */
- set_debugreg(0UL, 7);
+ /* Reset the control register for HW Breakpoint */
+ set_debugreg(DR7_FIXED_1, 7);
/* Zero-out the individual HW breakpoint address registers */
set_debugreg(0UL, 0);
@@ -125,9 +133,12 @@ static __always_inline unsigned long local_db_save(void)
return 0;
get_debugreg(dr7, 7);
- dr7 &= ~0x400; /* architecturally set bit */
+
+ /* Architecturally set bit */
+ dr7 &= ~DR7_FIXED_1;
if (dr7)
- set_debugreg(0, 7);
+ set_debugreg(DR7_FIXED_1, 7);
+
/*
* Ensure the compiler doesn't lower the above statements into
* the critical section; disabling breakpoints late would not
diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index edebf1020e04..6bb3d9a86abe 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -92,8 +92,6 @@ struct irq_cfg {
extern struct irq_cfg *irq_cfg(unsigned int irq);
extern struct irq_cfg *irqd_cfg(struct irq_data *irq_data);
-extern void lock_vector_lock(void);
-extern void unlock_vector_lock(void);
#ifdef CONFIG_SMP
extern void vector_schedule_cleanup(struct irq_cfg *);
extern void irq_complete_move(struct irq_cfg *cfg);
@@ -101,12 +99,16 @@ extern void irq_complete_move(struct irq_cfg *cfg);
static inline void vector_schedule_cleanup(struct irq_cfg *c) { }
static inline void irq_complete_move(struct irq_cfg *c) { }
#endif
-
extern void apic_ack_edge(struct irq_data *data);
-#else /* CONFIG_IRQ_DOMAIN_HIERARCHY */
+#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
+
+#ifdef CONFIG_X86_LOCAL_APIC
+extern void lock_vector_lock(void);
+extern void unlock_vector_lock(void);
+#else
static inline void lock_vector_lock(void) {}
static inline void unlock_vector_lock(void) {}
-#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */
+#endif
/* Statistics */
extern atomic_t irq_err_count;
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 1c2db11a2c3c..2b75fe80fcb2 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -44,13 +44,13 @@ static __always_inline void native_irq_enable(void)
static __always_inline void native_safe_halt(void)
{
- mds_idle_clear_cpu_buffers();
+ x86_idle_clear_cpu_buffers();
asm volatile("sti; hlt": : :"memory");
}
static __always_inline void native_halt(void)
{
- mds_idle_clear_cpu_buffers();
+ x86_idle_clear_cpu_buffers();
asm volatile("hlt": : :"memory");
}
diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index cfb22f8c451a..861d080ed4c6 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -47,7 +47,6 @@ KVM_X86_OP(set_idt)
KVM_X86_OP(get_gdt)
KVM_X86_OP(set_gdt)
KVM_X86_OP(sync_dirty_debug_regs)
-KVM_X86_OP(set_dr6)
KVM_X86_OP(set_dr7)
KVM_X86_OP(cache_reg)
KVM_X86_OP(get_rflags)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index e4dd840e0bec..d27df86aa62c 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -31,6 +31,7 @@
#include <asm/apic.h>
#include <asm/pvclock-abi.h>
+#include <asm/debugreg.h>
#include <asm/desc.h>
#include <asm/mtrr.h>
#include <asm/msr-index.h>
@@ -246,7 +247,6 @@ enum x86_intercept_stage;
#define DR7_BP_EN_MASK 0x000000ff
#define DR7_GE (1 << 9)
#define DR7_GD (1 << 13)
-#define DR7_FIXED_1 0x00000400
#define DR7_VOLATILE 0xffff2bff
#define KVM_GUESTDBG_VALID_MASK \
@@ -1627,6 +1627,12 @@ static inline u16 kvm_lapic_irq_dest_mode(bool dest_mode_logical)
return dest_mode_logical ? APIC_DEST_LOGICAL : APIC_DEST_PHYSICAL;
}
+enum kvm_x86_run_flags {
+ KVM_RUN_FORCE_IMMEDIATE_EXIT = BIT(0),
+ KVM_RUN_LOAD_GUEST_DR6 = BIT(1),
+ KVM_RUN_LOAD_DEBUGCTL = BIT(2),
+};
+
struct kvm_x86_ops {
const char *name;
@@ -1654,6 +1660,12 @@ struct kvm_x86_ops {
void (*vcpu_load)(struct kvm_vcpu *vcpu, int cpu);
void (*vcpu_put)(struct kvm_vcpu *vcpu);
+ /*
+ * Mask of DEBUGCTL bits that are owned by the host, i.e. that need to
+ * match the host's value even while the guest is active.
+ */
+ const u64 HOST_OWNED_DEBUGCTL;
+
void (*update_exception_bitmap)(struct kvm_vcpu *vcpu);
int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr);
int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr);
@@ -1675,7 +1687,6 @@ struct kvm_x86_ops {
void (*get_gdt)(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
void (*set_gdt)(struct kvm_vcpu *vcpu, struct desc_ptr *dt);
void (*sync_dirty_debug_regs)(struct kvm_vcpu *vcpu);
- void (*set_dr6)(struct kvm_vcpu *vcpu, unsigned long value);
void (*set_dr7)(struct kvm_vcpu *vcpu, unsigned long value);
void (*cache_reg)(struct kvm_vcpu *vcpu, enum kvm_reg reg);
unsigned long (*get_rflags)(struct kvm_vcpu *vcpu);
@@ -1706,7 +1717,7 @@ struct kvm_x86_ops {
int (*vcpu_pre_run)(struct kvm_vcpu *vcpu);
enum exit_fastpath_completion (*vcpu_run)(struct kvm_vcpu *vcpu,
- bool force_immediate_exit);
+ u64 run_flags);
int (*handle_exit)(struct kvm_vcpu *vcpu,
enum exit_fastpath_completion exit_fastpath);
int (*skip_emulated_instruction)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 5f0bc6a6d025..a42439c2ed24 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -275,11 +275,11 @@ int hv_unmap_ioapic_interrupt(int ioapic_id, struct hv_interrupt_entry *entry);
#ifdef CONFIG_AMD_MEM_ENCRYPT
bool hv_ghcb_negotiate_protocol(void);
void __noreturn hv_ghcb_terminate(unsigned int set, unsigned int reason);
-int hv_snp_boot_ap(u32 cpu, unsigned long start_ip);
+int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip);
#else
static inline bool hv_ghcb_negotiate_protocol(void) { return false; }
static inline void hv_ghcb_terminate(unsigned int set, unsigned int reason) {}
-static inline int hv_snp_boot_ap(u32 cpu, unsigned long start_ip) { return 0; }
+static inline int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip) { return 0; }
#endif
#if defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST)
@@ -313,6 +313,7 @@ static __always_inline u64 hv_raw_get_msr(unsigned int reg)
{
return __rdmsr(reg);
}
+int hv_apicid_to_vp_index(u32 apic_id);
#else /* CONFIG_HYPERV */
static inline void hyperv_init(void) {}
@@ -334,6 +335,7 @@ static inline void hv_set_msr(unsigned int reg, u64 value) { }
static inline u64 hv_get_msr(unsigned int reg) { return 0; }
static inline void hv_set_non_nested_msr(unsigned int reg, u64 value) { }
static inline u64 hv_get_non_nested_msr(unsigned int reg) { return 0; }
+static inline int hv_apicid_to_vp_index(u32 apic_id) { return -EINVAL; }
#endif /* CONFIG_HYPERV */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index ac25f9eb5912..2b6e3127ef4e 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -417,6 +417,7 @@
#define DEBUGCTLMSR_FREEZE_PERFMON_ON_PMI (1UL << 12)
#define DEBUGCTLMSR_FREEZE_IN_SMM_BIT 14
#define DEBUGCTLMSR_FREEZE_IN_SMM (1UL << DEBUGCTLMSR_FREEZE_IN_SMM_BIT)
+#define DEBUGCTLMSR_RTM_DEBUG BIT(15)
#define MSR_PEBS_FRONTEND 0x000003f7
@@ -621,6 +622,7 @@
#define MSR_AMD64_OSVW_STATUS 0xc0010141
#define MSR_AMD_PPIN_CTL 0xc00102f0
#define MSR_AMD_PPIN 0xc00102f1
+#define MSR_AMD64_CPUID_FN_7 0xc0011002
#define MSR_AMD64_CPUID_FN_1 0xc0011004
#define MSR_AMD64_LS_CFG 0xc0011020
#define MSR_AMD64_DC_CFG 0xc0011022
diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h
index 3e4e85f71a6a..7f9a97c572fe 100644
--- a/arch/x86/include/asm/mwait.h
+++ b/arch/x86/include/asm/mwait.h
@@ -44,8 +44,6 @@ static __always_inline void __monitorx(const void *eax, unsigned long ecx,
static __always_inline void __mwait(unsigned long eax, unsigned long ecx)
{
- mds_idle_clear_cpu_buffers();
-
/* "mwait %eax, %ecx;" */
asm volatile(".byte 0x0f, 0x01, 0xc9;"
:: "a" (eax), "c" (ecx));
@@ -80,7 +78,7 @@ static __always_inline void __mwait(unsigned long eax, unsigned long ecx)
static __always_inline void __mwaitx(unsigned long eax, unsigned long ebx,
unsigned long ecx)
{
- /* No MDS buffer clear as this is AMD/HYGON only */
+ /* No need for TSA buffer clearing on AMD */
/* "mwaitx %eax, %ebx, %ecx;" */
asm volatile(".byte 0x0f, 0x01, 0xfb;"
@@ -98,7 +96,7 @@ static __always_inline void __mwaitx(unsigned long eax, unsigned long ebx,
*/
static __always_inline void __sti_mwait(unsigned long eax, unsigned long ecx)
{
- mds_idle_clear_cpu_buffers();
+
/* "mwait %eax, %ecx;" */
asm volatile("sti; .byte 0x0f, 0x01, 0xc9;"
:: "a" (eax), "c" (ecx));
@@ -116,21 +114,29 @@ static __always_inline void __sti_mwait(unsigned long eax, unsigned long ecx)
*/
static __always_inline void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
{
+ if (need_resched())
+ return;
+
+ x86_idle_clear_cpu_buffers();
+
if (static_cpu_has_bug(X86_BUG_MONITOR) || !current_set_polling_and_test()) {
const void *addr = &current_thread_info()->flags;
alternative_input("", "clflush (%[addr])", X86_BUG_CLFLUSH_MONITOR, [addr] "a" (addr));
__monitor(addr, 0, 0);
- if (!need_resched()) {
- if (ecx & 1) {
- __mwait(eax, ecx);
- } else {
- __sti_mwait(eax, ecx);
- raw_local_irq_disable();
- }
+ if (need_resched())
+ goto out;
+
+ if (ecx & 1) {
+ __mwait(eax, ecx);
+ } else {
+ __sti_mwait(eax, ecx);
+ raw_local_irq_disable();
}
}
+
+out:
current_clr_polling();
}
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index f7bb0016d7d9..331f6a05535d 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -315,25 +315,31 @@
.endm
/*
- * Macro to execute VERW instruction that mitigate transient data sampling
- * attacks such as MDS. On affected systems a microcode update overloaded VERW
- * instruction to also clear the CPU buffers. VERW clobbers CFLAGS.ZF.
- *
+ * Macro to execute VERW insns that mitigate transient data sampling
+ * attacks such as MDS or TSA. On affected systems a microcode update
+ * overloaded VERW insns to also clear the CPU buffers. VERW clobbers
+ * CFLAGS.ZF.
* Note: Only the memory operand variant of VERW clears the CPU buffers.
*/
-.macro CLEAR_CPU_BUFFERS
+.macro __CLEAR_CPU_BUFFERS feature
#ifdef CONFIG_X86_64
- ALTERNATIVE "", "verw mds_verw_sel(%rip)", X86_FEATURE_CLEAR_CPU_BUF
+ ALTERNATIVE "", "verw x86_verw_sel(%rip)", \feature
#else
/*
* In 32bit mode, the memory operand must be a %cs reference. The data
* segments may not be usable (vm86 mode), and the stack segment may not
* be flat (ESPFIX32).
*/
- ALTERNATIVE "", "verw %cs:mds_verw_sel", X86_FEATURE_CLEAR_CPU_BUF
+ ALTERNATIVE "", "verw %cs:x86_verw_sel", \feature
#endif
.endm
+#define CLEAR_CPU_BUFFERS \
+ __CLEAR_CPU_BUFFERS X86_FEATURE_CLEAR_CPU_BUF
+
+#define VM_CLEAR_CPU_BUFFERS \
+ __CLEAR_CPU_BUFFERS X86_FEATURE_CLEAR_CPU_BUF_VM
+
#ifdef CONFIG_X86_64
.macro CLEAR_BRANCH_HISTORY
ALTERNATIVE "", "call clear_bhb_loop", X86_FEATURE_CLEAR_BHB_LOOP
@@ -582,24 +588,24 @@ DECLARE_STATIC_KEY_FALSE(switch_to_cond_stibp);
DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb);
DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
-DECLARE_STATIC_KEY_FALSE(mds_idle_clear);
+DECLARE_STATIC_KEY_FALSE(cpu_buf_idle_clear);
DECLARE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush);
DECLARE_STATIC_KEY_FALSE(mmio_stale_data_clear);
-extern u16 mds_verw_sel;
+extern u16 x86_verw_sel;
#include <asm/segment.h>
/**
- * mds_clear_cpu_buffers - Mitigation for MDS and TAA vulnerability
+ * x86_clear_cpu_buffers - Buffer clearing support for different x86 CPU vulns
*
* This uses the otherwise unused and obsolete VERW instruction in
* combination with microcode which triggers a CPU buffer flush when the
* instruction is executed.
*/
-static __always_inline void mds_clear_cpu_buffers(void)
+static __always_inline void x86_clear_cpu_buffers(void)
{
static const u16 ds = __KERNEL_DS;
@@ -616,14 +622,15 @@ static __always_inline void mds_clear_cpu_buffers(void)
}
/**
- * mds_idle_clear_cpu_buffers - Mitigation for MDS vulnerability
+ * x86_idle_clear_cpu_buffers - Buffer clearing support in idle for the MDS
+ * and TSA vulnerabilities.
*
* Clear CPU buffers if the corresponding static key is enabled
*/
-static __always_inline void mds_idle_clear_cpu_buffers(void)
+static __always_inline void x86_idle_clear_cpu_buffers(void)
{
- if (static_branch_likely(&mds_idle_clear))
- mds_clear_cpu_buffers();
+ if (static_branch_likely(&cpu_buf_idle_clear))
+ x86_clear_cpu_buffers();
}
#endif /* __ASSEMBLY__ */
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index b5b633294061..2d13ef1f4b05 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -97,7 +97,7 @@ void tdx_init(void);
typedef u64 (*sc_func_t)(u64 fn, struct tdx_module_args *args);
-static inline u64 sc_retry(sc_func_t func, u64 fn,
+static __always_inline u64 sc_retry(sc_func_t func, u64 fn,
struct tdx_module_args *args)
{
int retry = RDRAND_RETRY_LOOPS;
diff --git a/arch/x86/include/uapi/asm/debugreg.h b/arch/x86/include/uapi/asm/debugreg.h
index 0007ba077c0c..41da492dfb01 100644
--- a/arch/x86/include/uapi/asm/debugreg.h
+++ b/arch/x86/include/uapi/asm/debugreg.h
@@ -15,7 +15,26 @@
which debugging register was responsible for the trap. The other bits
are either reserved or not of interest to us. */
-/* Define reserved bits in DR6 which are always set to 1 */
+/*
+ * Define bits in DR6 which are set to 1 by default.
+ *
+ * This is also the DR6 architectural value following Power-up, Reset or INIT.
+ *
+ * Note, with the introduction of Bus Lock Detection (BLD) and Restricted
+ * Transactional Memory (RTM), the DR6 register has been modified:
+ *
+ * 1) BLD flag (bit 11) is no longer reserved to 1 if the CPU supports
+ * Bus Lock Detection. The assertion of a bus lock could clear it.
+ *
+ * 2) RTM flag (bit 16) is no longer reserved to 1 if the CPU supports
+ * restricted transactional memory. #DB occurred inside an RTM region
+ * could clear it.
+ *
+ * Apparently, DR6.BLD and DR6.RTM are active low bits.
+ *
+ * As a result, DR6_RESERVED is an incorrect name now, but it is kept for
+ * compatibility.
+ */
#define DR6_RESERVED (0xFFFF0FF0)
#define DR_TRAP0 (0x1) /* db0 */
generated by cgit v1.2.3 (git 2.39.0) at 2025-08-25 17:27:43 +0300