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-rw-r--r--arch/x86/entry/common.c638
1 files changed, 60 insertions, 578 deletions
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index f09288431f28..48512c7944e7 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -10,20 +10,13 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
+#include <linux/entry-common.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
-#include <linux/tracehook.h>
-#include <linux/audit.h>
-#include <linux/seccomp.h>
-#include <linux/signal.h>
#include <linux/export.h>
-#include <linux/context_tracking.h>
-#include <linux/user-return-notifier.h>
#include <linux/nospec.h>
-#include <linux/uprobes.h>
-#include <linux/livepatch.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
@@ -42,343 +35,12 @@
#include <asm/syscall.h>
#include <asm/irq_stack.h>
-#define CREATE_TRACE_POINTS
-#include <trace/events/syscalls.h>
-
-/* Check that the stack and regs on entry from user mode are sane. */
-static noinstr void check_user_regs(struct pt_regs *regs)
-{
- if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) {
- /*
- * Make sure that the entry code gave us a sensible EFLAGS
- * register. Native because we want to check the actual CPU
- * state, not the interrupt state as imagined by Xen.
- */
- unsigned long flags = native_save_fl();
- WARN_ON_ONCE(flags & (X86_EFLAGS_AC | X86_EFLAGS_DF |
- X86_EFLAGS_NT));
-
- /* We think we came from user mode. Make sure pt_regs agrees. */
- WARN_ON_ONCE(!user_mode(regs));
-
- /*
- * All entries from user mode (except #DF) should be on the
- * normal thread stack and should have user pt_regs in the
- * correct location.
- */
- WARN_ON_ONCE(!on_thread_stack());
- WARN_ON_ONCE(regs != task_pt_regs(current));
- }
-}
-
-#ifdef CONFIG_CONTEXT_TRACKING
-/**
- * enter_from_user_mode - Establish state when coming from user mode
- *
- * Syscall entry disables interrupts, but user mode is traced as interrupts
- * enabled. Also with NO_HZ_FULL RCU might be idle.
- *
- * 1) Tell lockdep that interrupts are disabled
- * 2) Invoke context tracking if enabled to reactivate RCU
- * 3) Trace interrupts off state
- */
-static noinstr void enter_from_user_mode(void)
-{
- enum ctx_state state = ct_state();
-
- lockdep_hardirqs_off(CALLER_ADDR0);
- user_exit_irqoff();
-
- instrumentation_begin();
- CT_WARN_ON(state != CONTEXT_USER);
- trace_hardirqs_off_finish();
- instrumentation_end();
-}
-#else
-static __always_inline void enter_from_user_mode(void)
-{
- lockdep_hardirqs_off(CALLER_ADDR0);
- instrumentation_begin();
- trace_hardirqs_off_finish();
- instrumentation_end();
-}
-#endif
-
-/**
- * exit_to_user_mode - Fixup state when exiting to user mode
- *
- * Syscall exit enables interrupts, but the kernel state is interrupts
- * disabled when this is invoked. Also tell RCU about it.
- *
- * 1) Trace interrupts on state
- * 2) Invoke context tracking if enabled to adjust RCU state
- * 3) Clear CPU buffers if CPU is affected by MDS and the migitation is on.
- * 4) Tell lockdep that interrupts are enabled
- */
-static __always_inline void exit_to_user_mode(void)
-{
- instrumentation_begin();
- trace_hardirqs_on_prepare();
- lockdep_hardirqs_on_prepare(CALLER_ADDR0);
- instrumentation_end();
-
- user_enter_irqoff();
- mds_user_clear_cpu_buffers();
- lockdep_hardirqs_on(CALLER_ADDR0);
-}
-
-static void do_audit_syscall_entry(struct pt_regs *regs, u32 arch)
-{
-#ifdef CONFIG_X86_64
- if (arch == AUDIT_ARCH_X86_64) {
- audit_syscall_entry(regs->orig_ax, regs->di,
- regs->si, regs->dx, regs->r10);
- } else
-#endif
- {
- audit_syscall_entry(regs->orig_ax, regs->bx,
- regs->cx, regs->dx, regs->si);
- }
-}
-
-/*
- * Returns the syscall nr to run (which should match regs->orig_ax) or -1
- * to skip the syscall.
- */
-static long syscall_trace_enter(struct pt_regs *regs)
-{
- u32 arch = in_ia32_syscall() ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
-
- struct thread_info *ti = current_thread_info();
- unsigned long ret = 0;
- u32 work;
-
- work = READ_ONCE(ti->flags);
-
- if (work & (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU)) {
- ret = tracehook_report_syscall_entry(regs);
- if (ret || (work & _TIF_SYSCALL_EMU))
- return -1L;
- }
-
-#ifdef CONFIG_SECCOMP
- /*
- * Do seccomp after ptrace, to catch any tracer changes.
- */
- if (work & _TIF_SECCOMP) {
- struct seccomp_data sd;
-
- sd.arch = arch;
- sd.nr = regs->orig_ax;
- sd.instruction_pointer = regs->ip;
-#ifdef CONFIG_X86_64
- if (arch == AUDIT_ARCH_X86_64) {
- sd.args[0] = regs->di;
- sd.args[1] = regs->si;
- sd.args[2] = regs->dx;
- sd.args[3] = regs->r10;
- sd.args[4] = regs->r8;
- sd.args[5] = regs->r9;
- } else
-#endif
- {
- sd.args[0] = regs->bx;
- sd.args[1] = regs->cx;
- sd.args[2] = regs->dx;
- sd.args[3] = regs->si;
- sd.args[4] = regs->di;
- sd.args[5] = regs->bp;
- }
-
- ret = __secure_computing(&sd);
- if (ret == -1)
- return ret;
- }
-#endif
-
- if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
- trace_sys_enter(regs, regs->orig_ax);
-
- do_audit_syscall_entry(regs, arch);
-
- return ret ?: regs->orig_ax;
-}
-
-#define EXIT_TO_USERMODE_LOOP_FLAGS \
- (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
- _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY | _TIF_PATCH_PENDING)
-
-static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags)
-{
- /*
- * In order to return to user mode, we need to have IRQs off with
- * none of EXIT_TO_USERMODE_LOOP_FLAGS set. Several of these flags
- * can be set at any time on preemptible kernels if we have IRQs on,
- * so we need to loop. Disabling preemption wouldn't help: doing the
- * work to clear some of the flags can sleep.
- */
- while (true) {
- /* We have work to do. */
- local_irq_enable();
-
- if (cached_flags & _TIF_NEED_RESCHED)
- schedule();
-
- if (cached_flags & _TIF_UPROBE)
- uprobe_notify_resume(regs);
-
- if (cached_flags & _TIF_PATCH_PENDING)
- klp_update_patch_state(current);
-
- /* deal with pending signal delivery */
- if (cached_flags & _TIF_SIGPENDING)
- do_signal(regs);
-
- if (cached_flags & _TIF_NOTIFY_RESUME) {
- clear_thread_flag(TIF_NOTIFY_RESUME);
- tracehook_notify_resume(regs);
- rseq_handle_notify_resume(NULL, regs);
- }
-
- if (cached_flags & _TIF_USER_RETURN_NOTIFY)
- fire_user_return_notifiers();
-
- /* Disable IRQs and retry */
- local_irq_disable();
-
- cached_flags = READ_ONCE(current_thread_info()->flags);
-
- if (!(cached_flags & EXIT_TO_USERMODE_LOOP_FLAGS))
- break;
- }
-}
-
-static void __prepare_exit_to_usermode(struct pt_regs *regs)
-{
- struct thread_info *ti = current_thread_info();
- u32 cached_flags;
-
- addr_limit_user_check();
-
- lockdep_assert_irqs_disabled();
- lockdep_sys_exit();
-
- cached_flags = READ_ONCE(ti->flags);
-
- if (unlikely(cached_flags & EXIT_TO_USERMODE_LOOP_FLAGS))
- exit_to_usermode_loop(regs, cached_flags);
-
- /* Reload ti->flags; we may have rescheduled above. */
- cached_flags = READ_ONCE(ti->flags);
-
- if (unlikely(cached_flags & _TIF_IO_BITMAP))
- tss_update_io_bitmap();
-
- fpregs_assert_state_consistent();
- if (unlikely(cached_flags & _TIF_NEED_FPU_LOAD))
- switch_fpu_return();
-
-#ifdef CONFIG_COMPAT
- /*
- * Compat syscalls set TS_COMPAT. Make sure we clear it before
- * returning to user mode. We need to clear it *after* signal
- * handling, because syscall restart has a fixup for compat
- * syscalls. The fixup is exercised by the ptrace_syscall_32
- * selftest.
- *
- * We also need to clear TS_REGS_POKED_I386: the 32-bit tracer
- * special case only applies after poking regs and before the
- * very next return to user mode.
- */
- ti->status &= ~(TS_COMPAT|TS_I386_REGS_POKED);
-#endif
-}
-
-static noinstr void prepare_exit_to_usermode(struct pt_regs *regs)
-{
- instrumentation_begin();
- __prepare_exit_to_usermode(regs);
- instrumentation_end();
- exit_to_user_mode();
-}
-
-#define SYSCALL_EXIT_WORK_FLAGS \
- (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
- _TIF_SINGLESTEP | _TIF_SYSCALL_TRACEPOINT)
-
-static void syscall_slow_exit_work(struct pt_regs *regs, u32 cached_flags)
-{
- bool step;
-
- audit_syscall_exit(regs);
-
- if (cached_flags & _TIF_SYSCALL_TRACEPOINT)
- trace_sys_exit(regs, regs->ax);
-
- /*
- * If TIF_SYSCALL_EMU is set, we only get here because of
- * TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
- * We already reported this syscall instruction in
- * syscall_trace_enter().
- */
- step = unlikely(
- (cached_flags & (_TIF_SINGLESTEP | _TIF_SYSCALL_EMU))
- == _TIF_SINGLESTEP);
- if (step || cached_flags & _TIF_SYSCALL_TRACE)
- tracehook_report_syscall_exit(regs, step);
-}
-
-static void __syscall_return_slowpath(struct pt_regs *regs)
-{
- struct thread_info *ti = current_thread_info();
- u32 cached_flags = READ_ONCE(ti->flags);
-
- CT_WARN_ON(ct_state() != CONTEXT_KERNEL);
-
- if (IS_ENABLED(CONFIG_PROVE_LOCKING) &&
- WARN(irqs_disabled(), "syscall %ld left IRQs disabled", regs->orig_ax))
- local_irq_enable();
-
- rseq_syscall(regs);
-
- /*
- * First do one-time work. If these work items are enabled, we
- * want to run them exactly once per syscall exit with IRQs on.
- */
- if (unlikely(cached_flags & SYSCALL_EXIT_WORK_FLAGS))
- syscall_slow_exit_work(regs, cached_flags);
-
- local_irq_disable();
- __prepare_exit_to_usermode(regs);
-}
-
-/*
- * Called with IRQs on and fully valid regs. Returns with IRQs off in a
- * state such that we can immediately switch to user mode.
- */
-__visible noinstr void syscall_return_slowpath(struct pt_regs *regs)
-{
- instrumentation_begin();
- __syscall_return_slowpath(regs);
- instrumentation_end();
- exit_to_user_mode();
-}
-
#ifdef CONFIG_X86_64
__visible noinstr void do_syscall_64(unsigned long nr, struct pt_regs *regs)
{
- struct thread_info *ti;
+ nr = syscall_enter_from_user_mode(regs, nr);
- check_user_regs(regs);
-
- enter_from_user_mode();
instrumentation_begin();
-
- local_irq_enable();
- ti = current_thread_info();
- if (READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY)
- nr = syscall_trace_enter(regs);
-
if (likely(nr < NR_syscalls)) {
nr = array_index_nospec(nr, NR_syscalls);
regs->ax = sys_call_table[nr](regs);
@@ -390,66 +52,55 @@ __visible noinstr void do_syscall_64(unsigned long nr, struct pt_regs *regs)
regs->ax = x32_sys_call_table[nr](regs);
#endif
}
- __syscall_return_slowpath(regs);
-
instrumentation_end();
- exit_to_user_mode();
+ syscall_exit_to_user_mode(regs);
}
#endif
#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
-/*
- * Does a 32-bit syscall. Called with IRQs on in CONTEXT_KERNEL. Does
- * all entry and exit work and returns with IRQs off. This function is
- * extremely hot in workloads that use it, and it's usually called from
- * do_fast_syscall_32, so forcibly inline it to improve performance.
- */
-static void do_syscall_32_irqs_on(struct pt_regs *regs)
+static __always_inline unsigned int syscall_32_enter(struct pt_regs *regs)
{
- struct thread_info *ti = current_thread_info();
unsigned int nr = (unsigned int)regs->orig_ax;
-#ifdef CONFIG_IA32_EMULATION
- ti->status |= TS_COMPAT;
-#endif
-
- if (READ_ONCE(ti->flags) & _TIF_WORK_SYSCALL_ENTRY) {
- /*
- * Subtlety here: if ptrace pokes something larger than
- * 2^32-1 into orig_ax, this truncates it. This may or
- * may not be necessary, but it matches the old asm
- * behavior.
- */
- nr = syscall_trace_enter(regs);
- }
+ if (IS_ENABLED(CONFIG_IA32_EMULATION))
+ current_thread_info()->status |= TS_COMPAT;
+ /*
+ * Subtlety here: if ptrace pokes something larger than 2^32-1 into
+ * orig_ax, the unsigned int return value truncates it. This may
+ * or may not be necessary, but it matches the old asm behavior.
+ */
+ return (unsigned int)syscall_enter_from_user_mode(regs, nr);
+}
+/*
+ * Invoke a 32-bit syscall. Called with IRQs on in CONTEXT_KERNEL.
+ */
+static __always_inline void do_syscall_32_irqs_on(struct pt_regs *regs,
+ unsigned int nr)
+{
if (likely(nr < IA32_NR_syscalls)) {
+ instrumentation_begin();
nr = array_index_nospec(nr, IA32_NR_syscalls);
regs->ax = ia32_sys_call_table[nr](regs);
+ instrumentation_end();
}
-
- __syscall_return_slowpath(regs);
}
/* Handles int $0x80 */
__visible noinstr void do_int80_syscall_32(struct pt_regs *regs)
{
- check_user_regs(regs);
+ unsigned int nr = syscall_32_enter(regs);
- enter_from_user_mode();
- instrumentation_begin();
-
- local_irq_enable();
- do_syscall_32_irqs_on(regs);
-
- instrumentation_end();
- exit_to_user_mode();
+ do_syscall_32_irqs_on(regs, nr);
+ syscall_exit_to_user_mode(regs);
}
-static bool __do_fast_syscall_32(struct pt_regs *regs)
+static noinstr bool __do_fast_syscall_32(struct pt_regs *regs)
{
+ unsigned int nr = syscall_32_enter(regs);
int res;
+ instrumentation_begin();
/* Fetch EBP from where the vDSO stashed it. */
if (IS_ENABLED(CONFIG_X86_64)) {
/*
@@ -462,17 +113,18 @@ static bool __do_fast_syscall_32(struct pt_regs *regs)
res = get_user(*(u32 *)&regs->bp,
(u32 __user __force *)(unsigned long)(u32)regs->sp);
}
+ instrumentation_end();
if (res) {
/* User code screwed up. */
regs->ax = -EFAULT;
- local_irq_disable();
- __prepare_exit_to_usermode(regs);
+ syscall_exit_to_user_mode(regs);
return false;
}
/* Now this is just like a normal syscall. */
- do_syscall_32_irqs_on(regs);
+ do_syscall_32_irqs_on(regs, nr);
+ syscall_exit_to_user_mode(regs);
return true;
}
@@ -485,9 +137,6 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs)
*/
unsigned long landing_pad = (unsigned long)current->mm->context.vdso +
vdso_image_32.sym_int80_landing_pad;
- bool success;
-
- check_user_regs(regs);
/*
* SYSENTER loses EIP, and even SYSCALL32 needs us to skip forward
@@ -496,17 +145,8 @@ __visible noinstr long do_fast_syscall_32(struct pt_regs *regs)
*/
regs->ip = landing_pad;
- enter_from_user_mode();
- instrumentation_begin();
-
- local_irq_enable();
- success = __do_fast_syscall_32(regs);
-
- instrumentation_end();
- exit_to_user_mode();
-
- /* If it failed, keep it simple: use IRET. */
- if (!success)
+ /* Invoke the syscall. If it failed, keep it simple: use IRET. */
+ if (!__do_fast_syscall_32(regs))
return 0;
#ifdef CONFIG_X86_64
@@ -558,197 +198,38 @@ SYSCALL_DEFINE0(ni_syscall)
return -ENOSYS;
}
-/**
- * idtentry_enter_cond_rcu - Handle state tracking on idtentry with conditional
- * RCU handling
- * @regs: Pointer to pt_regs of interrupted context
- *
- * Invokes:
- * - lockdep irqflag state tracking as low level ASM entry disabled
- * interrupts.
- *
- * - Context tracking if the exception hit user mode.
- *
- * - The hardirq tracer to keep the state consistent as low level ASM
- * entry disabled interrupts.
- *
- * 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
- * invoked on entry and rcu_irq_exit() on exit.
- *
- * Avoiding the rcu_irq_enter/exit() calls is an optimization but also
- * solves the problem of kernel mode pagefaults which can schedule, which
- * is not possible after invoking rcu_irq_enter() without undoing it.
- *
- * For user mode entries enter_from_user_mode() must be invoked to
- * 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
- *
- * The return value must be fed into the rcu_exit argument of
- * idtentry_exit_cond_rcu().
- */
-bool noinstr idtentry_enter_cond_rcu(struct pt_regs *regs)
+noinstr bool idtentry_enter_nmi(struct pt_regs *regs)
{
- if (user_mode(regs)) {
- check_user_regs(regs);
- enter_from_user_mode();
- return false;
- }
+ bool irq_state = lockdep_hardirqs_enabled();
- /*
- * If this entry hit the idle task invoke rcu_irq_enter() whether
- * RCU is watching or not.
- *
- * Interupts can nest when the first interrupt invokes softirq
- * processing on return which enables interrupts.
- *
- * Scheduler ticks in the idle task can mark quiescent state and
- * terminate a grace period, if and only if the timer interrupt is
- * not nested into another interrupt.
- *
- * Checking for __rcu_is_watching() here would prevent the nesting
- * interrupt to invoke rcu_irq_enter(). If that nested interrupt is
- * the tick then rcu_flavor_sched_clock_irq() would wrongfully
- * assume that it is the first interupt and eventually claim
- * quiescient state and end grace periods prematurely.
- *
- * Unconditionally invoke rcu_irq_enter() so RCU state stays
- * consistent.
- *
- * TINY_RCU does not support EQS, so let the compiler eliminate
- * this part when enabled.
- */
- if (!IS_ENABLED(CONFIG_TINY_RCU) && is_idle_task(current)) {
- /*
- * If RCU is not watching then the same careful
- * sequence vs. lockdep and tracing is required
- * as in enter_from_user_mode().
- */
- lockdep_hardirqs_off(CALLER_ADDR0);
- rcu_irq_enter();
- instrumentation_begin();
- trace_hardirqs_off_finish();
- instrumentation_end();
-
- return true;
- }
+ __nmi_enter();
+ lockdep_hardirqs_off(CALLER_ADDR0);
+ lockdep_hardirq_enter();
+ rcu_nmi_enter();
- /*
- * If RCU is watching then RCU only wants to check whether it needs
- * to restart the tick in NOHZ mode. rcu_irq_enter_check_tick()
- * already contains a warning when RCU is not watching, so no point
- * in having another one here.
- */
instrumentation_begin();
- rcu_irq_enter_check_tick();
- /* Use the combo lockdep/tracing function */
- trace_hardirqs_off();
+ trace_hardirqs_off_finish();
+ ftrace_nmi_enter();
instrumentation_end();
- return false;
-}
-
-static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
-{
- if (may_sched && !preempt_count()) {
- /* Sanity check RCU and thread stack */
- rcu_irq_exit_check_preempt();
- if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
- WARN_ON_ONCE(!on_thread_stack());
- if (need_resched())
- preempt_schedule_irq();
- }
- /* Covers both tracing and lockdep */
- trace_hardirqs_on();
+ return irq_state;
}
-/**
- * idtentry_exit_cond_rcu - Handle return from exception with conditional RCU
- * handling
- * @regs: Pointer to pt_regs (exception entry regs)
- * @rcu_exit: Invoke rcu_irq_exit() if true
- *
- * Depending on the return target (kernel/user) this runs the necessary
- * preemption and work checks if possible and reguired and returns to
- * the caller with interrupts disabled and no further work pending.
- *
- * 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.
- */
-void noinstr idtentry_exit_cond_rcu(struct pt_regs *regs, bool rcu_exit)
+noinstr void idtentry_exit_nmi(struct pt_regs *regs, bool restore)
{
- lockdep_assert_irqs_disabled();
-
- /* Check whether this returns to user mode */
- if (user_mode(regs)) {
- prepare_exit_to_usermode(regs);
- } else if (regs->flags & X86_EFLAGS_IF) {
- /*
- * If RCU was not watching on entry this needs to be done
- * carefully and needs the same ordering of lockdep/tracing
- * and RCU as the return to user mode path.
- */
- if (rcu_exit) {
- instrumentation_begin();
- /* Tell the tracer that IRET will enable interrupts */
- trace_hardirqs_on_prepare();
- lockdep_hardirqs_on_prepare(CALLER_ADDR0);
- instrumentation_end();
- rcu_irq_exit();
- lockdep_hardirqs_on(CALLER_ADDR0);
- return;
- }
-
- instrumentation_begin();
- idtentry_exit_cond_resched(regs, IS_ENABLED(CONFIG_PREEMPTION));
- instrumentation_end();
- } else {
- /*
- * IRQ flags state is correct already. Just tell RCU if it
- * was not watching on entry.
- */
- if (rcu_exit)
- rcu_irq_exit();
+ instrumentation_begin();
+ ftrace_nmi_exit();
+ if (restore) {
+ trace_hardirqs_on_prepare();
+ lockdep_hardirqs_on_prepare(CALLER_ADDR0);
}
-}
-
-/**
- * idtentry_enter_user - Handle state tracking on idtentry from user mode
- * @regs: Pointer to pt_regs of interrupted context
- *
- * 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)
-{
- check_user_regs(regs);
- enter_from_user_mode();
-}
-
-/**
- * idtentry_exit_user - Handle return from exception to user mode
- * @regs: Pointer to pt_regs (exception entry regs)
- *
- * Runs the necessary preemption and work checks and returns to the caller
- * with interrupts disabled and no further work pending.
- *
- * 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_user().
- */
-void noinstr idtentry_exit_user(struct pt_regs *regs)
-{
- lockdep_assert_irqs_disabled();
+ instrumentation_end();
- prepare_exit_to_usermode(regs);
+ rcu_nmi_exit();
+ lockdep_hardirq_exit();
+ if (restore)
+ lockdep_hardirqs_on(CALLER_ADDR0);
+ __nmi_exit();
}
#ifdef CONFIG_XEN_PV
@@ -800,9 +281,10 @@ 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;
+ irqentry_state_t state;
- rcu_exit = idtentry_enter_cond_rcu(regs);
+ state = irqentry_enter(regs);
old_regs = set_irq_regs(regs);
instrumentation_begin();
@@ -812,13 +294,13 @@ __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);
+ irqentry_exit_cond_resched();
instrumentation_end();
restore_inhcall(inhcall);
} else {
- idtentry_exit_cond_rcu(regs, rcu_exit);
+ irqentry_exit(regs, state);
}
}
#endif /* CONFIG_XEN_PV */