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-rw-r--r--arch/x86/Kconfig.debug3
-rw-r--r--arch/x86/entry/common.c88
-rw-r--r--arch/x86/include/asm/atomic.h2
-rw-r--r--arch/x86/include/asm/idtentry.h31
-rw-r--r--arch/x86/kernel/kvm.c6
-rw-r--r--arch/x86/kernel/nmi.c9
-rw-r--r--arch/x86/kernel/traps.c23
-rw-r--r--arch/x86/mm/fault.c6
-rw-r--r--arch/x86/mm/pat/set_memory.c2
9 files changed, 106 insertions, 64 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 0dd319e6e5b4..ee1d3c5834c6 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -3,6 +3,9 @@
config TRACE_IRQFLAGS_SUPPORT
def_bool y
+config TRACE_IRQFLAGS_NMI_SUPPORT
+ def_bool y
+
config EARLY_PRINTK_USB
bool
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index f09288431f28..54ad1890aefc 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -559,8 +559,7 @@ SYSCALL_DEFINE0(ni_syscall)
}
/**
- * idtentry_enter_cond_rcu - Handle state tracking on idtentry with conditional
- * RCU handling
+ * idtentry_enter - Handle state tracking on ordinary idtentries
* @regs: Pointer to pt_regs of interrupted context
*
* Invokes:
@@ -572,6 +571,9 @@ SYSCALL_DEFINE0(ni_syscall)
* - The hardirq tracer to keep the state consistent as low level ASM
* entry disabled interrupts.
*
+ * As a precondition, this requires that the entry came from user mode,
+ * idle, or a kernel context in which RCU is watching.
+ *
* For kernel mode entries RCU handling is done conditional. If RCU is
* watching then the only RCU requirement is to check whether the tick has
* to be restarted. If RCU is not watching then rcu_irq_enter() has to be
@@ -585,18 +587,21 @@ SYSCALL_DEFINE0(ni_syscall)
* establish the proper context for NOHZ_FULL. Otherwise scheduling on exit
* would not be possible.
*
- * Returns: True if RCU has been adjusted on a kernel entry
- * False otherwise
+ * Returns: An opaque object that must be passed to idtentry_exit()
*
- * The return value must be fed into the rcu_exit argument of
- * idtentry_exit_cond_rcu().
+ * The return value must be fed into the state argument of
+ * idtentry_exit().
*/
-bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
+noinstr idtentry_state_t idtentry_enter(struct pt_regs *regs)
{
+ idtentry_state_t ret = {
+ .exit_rcu = false,
+ };
+
if (user_mode(regs)) {
check_user_regs(regs);
enter_from_user_mode();
- return false;
+ return ret;
}
/*
@@ -634,7 +639,8 @@ bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
trace_hardirqs_off_finish();
instrumentation_end();
- return true;
+ ret.exit_rcu = true;
+ return ret;
}
/*
@@ -649,7 +655,7 @@ bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
trace_hardirqs_off();
instrumentation_end();
- return false;
+ return ret;
}
static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
@@ -667,10 +673,9 @@ static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
}
/**
- * idtentry_exit_cond_rcu - Handle return from exception with conditional RCU
- * handling
+ * idtentry_exit - Handle return from exception that used idtentry_enter()
* @regs: Pointer to pt_regs (exception entry regs)
- * @rcu_exit: Invoke rcu_irq_exit() if true
+ * @state: Return value from matching call to idtentry_enter()
*
* Depending on the return target (kernel/user) this runs the necessary
* preemption and work checks if possible and reguired and returns to
@@ -679,10 +684,10 @@ static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
* This is the last action before returning to the low level ASM code which
* just needs to return to the appropriate context.
*
- * Counterpart to idtentry_enter_cond_rcu(). The return value of the entry
- * function must be fed into the @rcu_exit argument.
+ * Counterpart to idtentry_enter(). The return value of the entry
+ * function must be fed into the @state argument.
*/
-void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
+noinstr void idtentry_exit(struct pt_regs *regs, idtentry_state_t state)
{
lockdep_assert_irqs_disabled();
@@ -695,7 +700,7 @@ void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
* carefully and needs the same ordering of lockdep/tracing
* and RCU as the return to user mode path.
*/
- if (rcu_exit) {
+ if (state.exit_rcu) {
instrumentation_begin();
/* Tell the tracer that IRET will enable interrupts */
trace_hardirqs_on_prepare();
@@ -714,7 +719,7 @@ void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
* IRQ flags state is correct already. Just tell RCU if it
* was not watching on entry.
*/
- if (rcu_exit)
+ if (state.exit_rcu)
rcu_irq_exit();
}
}
@@ -726,7 +731,7 @@ void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
* Invokes enter_from_user_mode() to establish the proper context for
* NOHZ_FULL. Otherwise scheduling on exit would not be possible.
*/
-void noinstr idtentry_enter_user(struct pt_regs *regs)
+noinstr void idtentry_enter_user(struct pt_regs *regs)
{
check_user_regs(regs);
enter_from_user_mode();
@@ -744,13 +749,47 @@ void noinstr idtentry_enter_user(struct pt_regs *regs)
*
* Counterpart to idtentry_enter_user().
*/
-void noinstr idtentry_exit_user(struct pt_regs *regs)
+noinstr void idtentry_exit_user(struct pt_regs *regs)
{
lockdep_assert_irqs_disabled();
prepare_exit_to_usermode(regs);
}
+noinstr bool idtentry_enter_nmi(struct pt_regs *regs)
+{
+ bool irq_state = lockdep_hardirqs_enabled();
+
+ __nmi_enter();
+ lockdep_hardirqs_off(CALLER_ADDR0);
+ lockdep_hardirq_enter();
+ rcu_nmi_enter();
+
+ instrumentation_begin();
+ trace_hardirqs_off_finish();
+ ftrace_nmi_enter();
+ instrumentation_end();
+
+ return irq_state;
+}
+
+noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore)
+{
+ instrumentation_begin();
+ ftrace_nmi_exit();
+ if (restore) {
+ trace_hardirqs_on_prepare();
+ lockdep_hardirqs_on_prepare(CALLER_ADDR0);
+ }
+ instrumentation_end();
+
+ rcu_nmi_exit();
+ lockdep_hardirq_exit();
+ if (restore)
+ lockdep_hardirqs_on(CALLER_ADDR0);
+ __nmi_exit();
+}
+
#ifdef CONFIG_XEN_PV
#ifndef CONFIG_PREEMPTION
/*
@@ -800,9 +839,10 @@ static void __xen_pv_evtchn_do_upcall(void)
__visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
{
struct pt_regs *old_regs;
- bool inhcall, rcu_exit;
+ bool inhcall;
+ idtentry_state_t state;
- rcu_exit = idtentry_enter_cond_rcu(regs);
+ state = idtentry_enter(regs);
old_regs = set_irq_regs(regs);
instrumentation_begin();
@@ -812,13 +852,13 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs)
set_irq_regs(old_regs);
inhcall = get_and_clear_inhcall();
- if (inhcall && !WARN_ON_ONCE(rcu_exit)) {
+ if (inhcall && !WARN_ON_ONCE(state.exit_rcu)) {
instrumentation_begin();
idtentry_exit_cond_resched(regs, true);
instrumentation_end();
restore_inhcall(inhcall);
} else {
- idtentry_exit_cond_rcu(regs, rcu_exit);
+ idtentry_exit(regs, state);
}
}
#endif /* CONFIG_XEN_PV */
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
index bf35e476a776..b6cac6e9bb70 100644
--- a/arch/x86/include/asm/atomic.h
+++ b/arch/x86/include/asm/atomic.h
@@ -14,8 +14,6 @@
* resource counting etc..
*/
-#define ATOMIC_INIT(i) { (i) }
-
/**
* arch_atomic_read - read atomic variable
* @v: pointer of type atomic_t
diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
index 80d3b30d3ee3..d74128c964f8 100644
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -13,8 +13,15 @@
void idtentry_enter_user(struct pt_regs *regs);
void idtentry_exit_user(struct pt_regs *regs);
-bool idtentry_enter_cond_rcu(struct pt_regs *regs);
-void idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit);
+typedef struct idtentry_state {
+ bool exit_rcu;
+} idtentry_state_t;
+
+idtentry_state_t idtentry_enter(struct pt_regs *regs);
+void idtentry_exit(struct pt_regs *regs, idtentry_state_t state);
+
+bool idtentry_enter_nmi(struct pt_regs *regs);
+void idtentry_exit_nmi(struct pt_regs *regs, bool irq_state);
/**
* DECLARE_IDTENTRY - Declare functions for simple IDT entry points
@@ -54,12 +61,12 @@ static __always_inline void __##func(struct pt_regs *regs); \
\
__visible noinstr void func(struct pt_regs *regs) \
{ \
- bool rcu_exit = idtentry_enter_cond_rcu(regs); \
+ idtentry_state_t state = idtentry_enter(regs); \
\
instrumentation_begin(); \
__##func (regs); \
instrumentation_end(); \
- idtentry_exit_cond_rcu(regs, rcu_exit); \
+ idtentry_exit(regs, state); \
} \
\
static __always_inline void __##func(struct pt_regs *regs)
@@ -101,12 +108,12 @@ static __always_inline void __##func(struct pt_regs *regs, \
__visible noinstr void func(struct pt_regs *regs, \
unsigned long error_code) \
{ \
- bool rcu_exit = idtentry_enter_cond_rcu(regs); \
+ idtentry_state_t state = idtentry_enter(regs); \
\
instrumentation_begin(); \
__##func (regs, error_code); \
instrumentation_end(); \
- idtentry_exit_cond_rcu(regs, rcu_exit); \
+ idtentry_exit(regs, state); \
} \
\
static __always_inline void __##func(struct pt_regs *regs, \
@@ -199,7 +206,7 @@ static __always_inline void __##func(struct pt_regs *regs, u8 vector); \
__visible noinstr void func(struct pt_regs *regs, \
unsigned long error_code) \
{ \
- bool rcu_exit = idtentry_enter_cond_rcu(regs); \
+ idtentry_state_t state = idtentry_enter(regs); \
\
instrumentation_begin(); \
irq_enter_rcu(); \
@@ -207,7 +214,7 @@ __visible noinstr void func(struct pt_regs *regs, \
__##func (regs, (u8)error_code); \
irq_exit_rcu(); \
instrumentation_end(); \
- idtentry_exit_cond_rcu(regs, rcu_exit); \
+ idtentry_exit(regs, state); \
} \
\
static __always_inline void __##func(struct pt_regs *regs, u8 vector)
@@ -241,7 +248,7 @@ static void __##func(struct pt_regs *regs); \
\
__visible noinstr void func(struct pt_regs *regs) \
{ \
- bool rcu_exit = idtentry_enter_cond_rcu(regs); \
+ idtentry_state_t state = idtentry_enter(regs); \
\
instrumentation_begin(); \
irq_enter_rcu(); \
@@ -249,7 +256,7 @@ __visible noinstr void func(struct pt_regs *regs) \
run_on_irqstack_cond(__##func, regs, regs); \
irq_exit_rcu(); \
instrumentation_end(); \
- idtentry_exit_cond_rcu(regs, rcu_exit); \
+ idtentry_exit(regs, state); \
} \
\
static noinline void __##func(struct pt_regs *regs)
@@ -270,7 +277,7 @@ static __always_inline void __##func(struct pt_regs *regs); \
\
__visible noinstr void func(struct pt_regs *regs) \
{ \
- bool rcu_exit = idtentry_enter_cond_rcu(regs); \
+ idtentry_state_t state = idtentry_enter(regs); \
\
instrumentation_begin(); \
__irq_enter_raw(); \
@@ -278,7 +285,7 @@ __visible noinstr void func(struct pt_regs *regs) \
__##func (regs); \
__irq_exit_raw(); \
instrumentation_end(); \
- idtentry_exit_cond_rcu(regs, rcu_exit); \
+ idtentry_exit(regs, state); \
} \
\
static __always_inline void __##func(struct pt_regs *regs)
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index df63786e7bfa..3f78482d9496 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -233,7 +233,7 @@ EXPORT_SYMBOL_GPL(kvm_read_and_reset_apf_flags);
noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token)
{
u32 reason = kvm_read_and_reset_apf_flags();
- bool rcu_exit;
+ idtentry_state_t state;
switch (reason) {
case KVM_PV_REASON_PAGE_NOT_PRESENT:
@@ -243,7 +243,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token)
return false;
}
- rcu_exit = idtentry_enter_cond_rcu(regs);
+ state = idtentry_enter(regs);
instrumentation_begin();
/*
@@ -264,7 +264,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token)
}
instrumentation_end();
- idtentry_exit_cond_rcu(regs, rcu_exit);
+ idtentry_exit(regs, state);
return true;
}
diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index d7c5e44b26f7..4fc9954a9560 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -330,7 +330,6 @@ static noinstr void default_do_nmi(struct pt_regs *regs)
__this_cpu_write(last_nmi_rip, regs->ip);
instrumentation_begin();
- trace_hardirqs_off_finish();
handled = nmi_handle(NMI_LOCAL, regs);
__this_cpu_add(nmi_stats.normal, handled);
@@ -417,8 +416,6 @@ static noinstr void default_do_nmi(struct pt_regs *regs)
unknown_nmi_error(reason, regs);
out:
- if (regs->flags & X86_EFLAGS_IF)
- trace_hardirqs_on_prepare();
instrumentation_end();
}
@@ -478,6 +475,8 @@ static DEFINE_PER_CPU(unsigned long, nmi_dr7);
DEFINE_IDTENTRY_RAW(exc_nmi)
{
+ bool irq_state;
+
if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id()))
return;
@@ -491,14 +490,14 @@ nmi_restart:
this_cpu_write(nmi_dr7, local_db_save());
- nmi_enter();
+ irq_state = idtentry_enter_nmi(regs);
inc_irq_stat(__nmi_count);
if (!ignore_nmis)
default_do_nmi(regs);
- nmi_exit();
+ idtentry_exit_nmi(regs, irq_state);
local_db_restore(this_cpu_read(nmi_dr7));
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index b7cb3e0716f7..8493f55e1167 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -245,7 +245,7 @@ static noinstr bool handle_bug(struct pt_regs *regs)
DEFINE_IDTENTRY_RAW(exc_invalid_op)
{
- bool rcu_exit;
+ idtentry_state_t state;
/*
* We use UD2 as a short encoding for 'CALL __WARN', as such
@@ -255,11 +255,11 @@ DEFINE_IDTENTRY_RAW(exc_invalid_op)
if (!user_mode(regs) && handle_bug(regs))
return;
- rcu_exit = idtentry_enter_cond_rcu(regs);
+ state = idtentry_enter(regs);
instrumentation_begin();
handle_invalid_op(regs);
instrumentation_end();
- idtentry_exit_cond_rcu(regs, rcu_exit);
+ idtentry_exit(regs, state);
}
DEFINE_IDTENTRY(exc_coproc_segment_overrun)
@@ -405,7 +405,7 @@ DEFINE_IDTENTRY_DF(exc_double_fault)
}
#endif
- nmi_enter();
+ idtentry_enter_nmi(regs);
instrumentation_begin();
notify_die(DIE_TRAP, str, regs, error_code, X86_TRAP_DF, SIGSEGV);
@@ -651,15 +651,12 @@ DEFINE_IDTENTRY_RAW(exc_int3)
instrumentation_end();
idtentry_exit_user(regs);
} else {
- nmi_enter();
+ bool irq_state = idtentry_enter_nmi(regs);
instrumentation_begin();
- trace_hardirqs_off_finish();
if (!do_int3(regs))
die("int3", regs, 0);
- if (regs->flags & X86_EFLAGS_IF)
- trace_hardirqs_on_prepare();
instrumentation_end();
- nmi_exit();
+ idtentry_exit_nmi(regs, irq_state);
}
}
@@ -867,9 +864,8 @@ out:
static __always_inline void exc_debug_kernel(struct pt_regs *regs,
unsigned long dr6)
{
- nmi_enter();
+ bool irq_state = idtentry_enter_nmi(regs);
instrumentation_begin();
- trace_hardirqs_off_finish();
/*
* If something gets miswired and we end up here for a user mode
@@ -886,10 +882,8 @@ static __always_inline void exc_debug_kernel(struct pt_regs *regs,
handle_debug(regs, dr6, false);
- if (regs->flags & X86_EFLAGS_IF)
- trace_hardirqs_on_prepare();
instrumentation_end();
- nmi_exit();
+ idtentry_exit_nmi(regs, irq_state);
}
static __always_inline void exc_debug_user(struct pt_regs *regs,
@@ -905,6 +899,7 @@ static __always_inline void exc_debug_user(struct pt_regs *regs,
instrumentation_begin();
handle_debug(regs, dr6, true);
+
instrumentation_end();
idtentry_exit_user(regs);
}
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 1ead568c0101..5e41949453cc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1377,7 +1377,7 @@ handle_page_fault(struct pt_regs *regs, unsigned long error_code,
DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault)
{
unsigned long address = read_cr2();
- bool rcu_exit;
+ idtentry_state_t state;
prefetchw(&current->mm->mmap_lock);
@@ -1412,11 +1412,11 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault)
* code reenabled RCU to avoid subsequent wreckage which helps
* debugability.
*/
- rcu_exit = idtentry_enter_cond_rcu(regs);
+ state = idtentry_enter(regs);
instrumentation_begin();
handle_page_fault(regs, error_code, address);
instrumentation_end();
- idtentry_exit_cond_rcu(regs, rcu_exit);
+ idtentry_exit(regs, state);
}
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 77e04304a2a7..d1b2a889f035 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -135,7 +135,7 @@ static inline void cpa_inc_2m_checked(void)
static inline void cpa_inc_4k_install(void)
{
- cpa_4k_install++;
+ data_race(cpa_4k_install++);
}
static inline void cpa_inc_lp_sameprot(int level)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 19:28:07 +0000