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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-05 06:05:46 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-05 06:05:46 +0200 |
commit | 125cfa0d4d143416ae217c26a72003baae93233d (patch) | |
tree | fb29ea571b34bf591789deb70cb6a263ba01bbdf | |
parent | Merge tag 'core-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kerne... (diff) | |
parent | Merge branch 'WIP.x86/entry' into x86/entry, to merge the latest generic code... (diff) | |
download | linux-125cfa0d4d143416ae217c26a72003baae93233d.tar.xz linux-125cfa0d4d143416ae217c26a72003baae93233d.zip |
Merge tag 'x86-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 conversion to generic entry code from Thomas Gleixner:
"The conversion of X86 syscall, interrupt and exception entry/exit
handling to the generic code.
Pretty much a straight-forward 1:1 conversion plus the consolidation
of the KVM handling of pending work before entering guest mode"
* tag 'x86-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kvm: Use __xfer_to_guest_mode_work_pending() in kvm_run_vcpu()
x86/kvm: Use generic xfer to guest work function
x86/entry: Cleanup idtentry_enter/exit
x86/entry: Use generic interrupt entry/exit code
x86/entry: Cleanup idtentry_entry/exit_user
x86/entry: Use generic syscall exit functionality
x86/entry: Use generic syscall entry function
x86/ptrace: Provide pt_regs helper for entry/exit
x86/entry: Move user return notifier out of loop
x86/entry: Consolidate 32/64 bit syscall entry
x86/entry: Consolidate check_user_regs()
x86: Correct noinstr qualifiers
x86/idtentry: Remove stale comment
-rw-r--r-- | arch/x86/Kconfig | 1 | ||||
-rw-r--r-- | arch/x86/entry/common.c | 632 | ||||
-rw-r--r-- | arch/x86/entry/entry_32.S | 2 | ||||
-rw-r--r-- | arch/x86/entry/entry_64.S | 2 | ||||
-rw-r--r-- | arch/x86/include/asm/entry-common.h | 76 | ||||
-rw-r--r-- | arch/x86/include/asm/idtentry.h | 45 | ||||
-rw-r--r-- | arch/x86/include/asm/ptrace.h | 5 | ||||
-rw-r--r-- | arch/x86/include/asm/signal.h | 1 | ||||
-rw-r--r-- | arch/x86/include/asm/thread_info.h | 5 | ||||
-rw-r--r-- | arch/x86/kernel/alternative.c | 2 | ||||
-rw-r--r-- | arch/x86/kernel/cpu/mce/core.c | 6 | ||||
-rw-r--r-- | arch/x86/kernel/kvm.c | 6 | ||||
-rw-r--r-- | arch/x86/kernel/signal.c | 3 | ||||
-rw-r--r-- | arch/x86/kernel/traps.c | 24 | ||||
-rw-r--r-- | arch/x86/kvm/Kconfig | 1 | ||||
-rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 11 | ||||
-rw-r--r-- | arch/x86/kvm/x86.c | 15 | ||||
-rw-r--r-- | arch/x86/mm/fault.c | 6 |
18 files changed, 174 insertions, 669 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5f17f1f2c4c9..fd03cefabd34 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -115,6 +115,7 @@ config X86 select GENERIC_CPU_AUTOPROBE select GENERIC_CPU_VULNERABILITIES select GENERIC_EARLY_IOREMAP + select GENERIC_ENTRY select GENERIC_FIND_FIRST_BIT select GENERIC_IOMAP select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 54ad1890aefc..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; - - check_user_regs(regs); + nr = syscall_enter_from_user_mode(regs, nr); - 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); - - enter_from_user_mode(); - instrumentation_begin(); + unsigned int nr = syscall_32_enter(regs); - 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 *)®s->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 @@ -558,204 +198,6 @@ SYSCALL_DEFINE0(ni_syscall) return -ENOSYS; } -/** - * idtentry_enter - Handle state tracking on ordinary idtentries - * @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. - * - * 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 - * 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: An opaque object that must be passed to idtentry_exit() - * - * The return value must be fed into the state argument of - * idtentry_exit(). - */ -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 ret; - } - - /* - * 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(); - - ret.exit_rcu = true; - return ret; - } - - /* - * 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(); - instrumentation_end(); - - return ret; -} - -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(); -} - -/** - * idtentry_exit - Handle return from exception that used idtentry_enter() - * @regs: Pointer to pt_regs (exception entry regs) - * @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 - * 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(). The return value of the entry - * function must be fed into the @state argument. - */ -noinstr void idtentry_exit(struct pt_regs *regs, idtentry_state_t state) -{ - 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 (state.exit_rcu) { - 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 (state.exit_rcu) - rcu_irq_exit(); - } -} - -/** - * 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. - */ -noinstr void 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(). - */ -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(); @@ -840,9 +282,9 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) { struct pt_regs *old_regs; bool inhcall; - idtentry_state_t state; + irqentry_state_t state; - state = idtentry_enter(regs); + state = irqentry_enter(regs); old_regs = set_irq_regs(regs); instrumentation_begin(); @@ -854,11 +296,11 @@ __visible noinstr void xen_pv_evtchn_do_upcall(struct pt_regs *regs) inhcall = get_and_clear_inhcall(); 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(regs, state); + irqentry_exit(regs, state); } } #endif /* CONFIG_XEN_PV */ diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 4430ee1fae71..29b7d52143e9 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -846,7 +846,7 @@ SYM_CODE_START(ret_from_fork) 2: /* When we fork, we trace the syscall return in the child, too. */ movl %esp, %eax - call syscall_return_slowpath + call syscall_exit_to_user_mode jmp .Lsyscall_32_done /* kernel thread */ diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 73c7e255256b..d2599c627d38 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -283,7 +283,7 @@ SYM_CODE_START(ret_from_fork) 2: UNWIND_HINT_REGS movq %rsp, %rdi - call syscall_return_slowpath /* returns with IRQs disabled */ + call syscall_exit_to_user_mode /* returns with IRQs disabled */ jmp swapgs_restore_regs_and_return_to_usermode 1: diff --git a/arch/x86/include/asm/entry-common.h b/arch/x86/include/asm/entry-common.h new file mode 100644 index 000000000000..a8f9315b9eae --- /dev/null +++ b/arch/x86/include/asm/entry-common.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _ASM_X86_ENTRY_COMMON_H +#define _ASM_X86_ENTRY_COMMON_H + +#include <linux/user-return-notifier.h> + +#include <asm/nospec-branch.h> +#include <asm/io_bitmap.h> +#include <asm/fpu/api.h> + +/* Check that the stack and regs on entry from user mode are sane. */ +static __always_inline void arch_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)); + } +} +#define arch_check_user_regs arch_check_user_regs + +#define ARCH_SYSCALL_EXIT_WORK (_TIF_SINGLESTEP) + +static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, + unsigned long ti_work) +{ + if (ti_work & _TIF_USER_RETURN_NOTIFY) + fire_user_return_notifiers(); + + if (unlikely(ti_work & _TIF_IO_BITMAP)) + tss_update_io_bitmap(); + + fpregs_assert_state_consistent(); + if (unlikely(ti_work & _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. + */ + current_thread_info()->status &= ~(TS_COMPAT | TS_I386_REGS_POKED); +#endif +} +#define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare + +static __always_inline void arch_exit_to_user_mode(void) +{ + mds_user_clear_cpu_buffers(); +} +#define arch_exit_to_user_mode arch_exit_to_user_mode + +#endif diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h index d74128c964f8..ff198fc2495e 100644 --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -6,20 +6,11 @@ #include <asm/trapnr.h> #ifndef __ASSEMBLY__ +#include <linux/entry-common.h> #include <linux/hardirq.h> #include <asm/irq_stack.h> -void idtentry_enter_user(struct pt_regs *regs); -void idtentry_exit_user(struct pt_regs *regs); - -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); @@ -52,8 +43,8 @@ void idtentry_exit_nmi(struct pt_regs *regs, bool irq_state); * The macro is written so it acts as function definition. Append the * body with a pair of curly brackets. * - * idtentry_enter() contains common code which has to be invoked before - * arbitrary code in the body. idtentry_exit() contains common code + * irqentry_enter() contains common code which has to be invoked before + * arbitrary code in the body. irqentry_exit() contains common code * which has to run before returning to the low level assembly code. */ #define DEFINE_IDTENTRY(func) \ @@ -61,12 +52,12 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - idtentry_state_t state = idtentry_enter(regs); \ + irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ __##func (regs); \ instrumentation_end(); \ - idtentry_exit(regs, state); \ + irqentry_exit(regs, state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) @@ -108,12 +99,12 @@ static __always_inline void __##func(struct pt_regs *regs, \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - idtentry_state_t state = idtentry_enter(regs); \ + irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ __##func (regs, error_code); \ instrumentation_end(); \ - idtentry_exit(regs, state); \ + irqentry_exit(regs, state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, \ @@ -168,7 +159,7 @@ __visible noinstr void func(struct pt_regs *regs) * body with a pair of curly brackets. * * Contrary to DEFINE_IDTENTRY_ERRORCODE() this does not invoke the - * idtentry_enter/exit() helpers before and after the body invocation. This + * irqentry_enter/exit() helpers before and after the body invocation. This * needs to be done in the body itself if applicable. Use if extra work * is required before the enter/exit() helpers are invoked. */ @@ -194,11 +185,9 @@ __visible noinstr void func(struct pt_regs *regs, unsigned long error_code) * to the function as error_code argument which needs to be truncated * to an u8 because the push is sign extending. * - * On 64-bit idtentry_enter/exit() are invoked in the ASM entry code before - * and after switching to the interrupt stack. On 32-bit this happens in C. - * * irq_enter/exit_rcu() are invoked before the function body and the - * KVM L1D flush request is set. + * KVM L1D flush request is set. Stack switching to the interrupt stack + * has to be done in the function body if necessary. */ #define DEFINE_IDTENTRY_IRQ(func) \ static __always_inline void __##func(struct pt_regs *regs, u8 vector); \ @@ -206,7 +195,7 @@ static __always_inline void __##func(struct pt_regs *regs, u8 vector); \ __visible noinstr void func(struct pt_regs *regs, \ unsigned long error_code) \ { \ - idtentry_state_t state = idtentry_enter(regs); \ + irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ irq_enter_rcu(); \ @@ -214,7 +203,7 @@ __visible noinstr void func(struct pt_regs *regs, \ __##func (regs, (u8)error_code); \ irq_exit_rcu(); \ instrumentation_end(); \ - idtentry_exit(regs, state); \ + irqentry_exit(regs, state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs, u8 vector) @@ -238,7 +227,7 @@ static __always_inline void __##func(struct pt_regs *regs, u8 vector) * DEFINE_IDTENTRY_SYSVEC - Emit code for system vector IDT entry points * @func: Function name of the entry point * - * idtentry_enter/exit() and irq_enter/exit_rcu() are invoked before the + * irqentry_enter/exit() and irq_enter/exit_rcu() are invoked before the * function body. KVM L1D flush request is set. * * Runs the function on the interrupt stack if the entry hit kernel mode @@ -248,7 +237,7 @@ static void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - idtentry_state_t state = idtentry_enter(regs); \ + irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ irq_enter_rcu(); \ @@ -256,7 +245,7 @@ __visible noinstr void func(struct pt_regs *regs) \ run_on_irqstack_cond(__##func, regs, regs); \ irq_exit_rcu(); \ instrumentation_end(); \ - idtentry_exit(regs, state); \ + irqentry_exit(regs, state); \ } \ \ static noinline void __##func(struct pt_regs *regs) @@ -277,7 +266,7 @@ static __always_inline void __##func(struct pt_regs *regs); \ \ __visible noinstr void func(struct pt_regs *regs) \ { \ - idtentry_state_t state = idtentry_enter(regs); \ + irqentry_state_t state = irqentry_enter(regs); \ \ instrumentation_begin(); \ __irq_enter_raw(); \ @@ -285,7 +274,7 @@ __visible noinstr void func(struct pt_regs *regs) \ __##func (regs); \ __irq_exit_raw(); \ instrumentation_end(); \ - idtentry_exit(regs, state); \ + irqentry_exit(regs, state); \ } \ \ static __always_inline void __##func(struct pt_regs *regs) diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index 255b2dde2c1b..40aa69d04862 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -209,6 +209,11 @@ static inline void user_stack_pointer_set(struct pt_regs *regs, regs->sp = val; } +static __always_inline bool regs_irqs_disabled(struct pt_regs *regs) +{ + return !(regs->flags & X86_EFLAGS_IF); +} + /* Query offset/name of register from its name/offset */ extern int regs_query_register_offset(const char *name); extern const char *regs_query_register_name(unsigned int offset); diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h index 33d3c88a7225..6fd8410a3910 100644 --- a/arch/x86/include/asm/signal.h +++ b/arch/x86/include/asm/signal.h @@ -35,7 +35,6 @@ typedef sigset_t compat_sigset_t; #endif /* __ASSEMBLY__ */ #include <uapi/asm/signal.h> #ifndef __ASSEMBLY__ -extern void do_signal(struct pt_regs *regs); #define __ARCH_HAS_SA_RESTORER diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 8de8ceccb8bc..267701ae3d86 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -133,11 +133,6 @@ struct thread_info { #define _TIF_X32 (1 << TIF_X32) #define _TIF_FSCHECK (1 << TIF_FSCHECK) -/* Work to do before invoking the actual syscall. */ -#define _TIF_WORK_SYSCALL_ENTRY \ - (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_AUDIT | \ - _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT) - /* flags to check in __switch_to() */ #define _TIF_WORK_CTXSW_BASE \ (_TIF_NOCPUID | _TIF_NOTSC | _TIF_BLOCKSTEP | \ diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 3abc1316f91b..c826cddae157 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1047,7 +1047,7 @@ static __always_inline int patch_cmp(const void *key, const void *elt) return 0; } -int noinstr poke_int3_handler(struct pt_regs *regs) +noinstr int poke_int3_handler(struct pt_regs *regs) { struct bp_patching_desc *desc; struct text_poke_loc *tp; diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index e76c1ddd35e7..f43a78bde670 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1215,7 +1215,7 @@ static void kill_me_maybe(struct callback_head *cb) * backing the user stack, tracing that reads the user stack will cause * potentially infinite recursion. */ -void noinstr do_machine_check(struct pt_regs *regs) +noinstr void do_machine_check(struct pt_regs *regs) { DECLARE_BITMAP(valid_banks, MAX_NR_BANKS); DECLARE_BITMAP(toclear, MAX_NR_BANKS); @@ -1930,11 +1930,11 @@ static __always_inline void exc_machine_check_kernel(struct pt_regs *regs) static __always_inline void exc_machine_check_user(struct pt_regs *regs) { - idtentry_enter_user(regs); + irqentry_enter_from_user_mode(regs); instrumentation_begin(); machine_check_vector(regs); instrumentation_end(); - idtentry_exit_user(regs); + irqentry_exit_to_user_mode(regs); } #ifdef CONFIG_X86_64 diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 3f78482d9496..233c77d056c9 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(); - idtentry_state_t state; + irqentry_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; } - state = idtentry_enter(regs); + state = irqentry_enter(regs); instrumentation_begin(); /* @@ -264,7 +264,7 @@ noinstr bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token) } instrumentation_end(); - idtentry_exit(regs, state); + irqentry_exit(regs, state); return true; } diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 399f97abee02..d5fa494c2304 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -25,6 +25,7 @@ #include <linux/user-return-notifier.h> #include <linux/uprobes.h> #include <linux/context_tracking.h> +#include <linux/entry-common.h> #include <linux/syscalls.h> #include <asm/processor.h> @@ -803,7 +804,7 @@ static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ -void do_signal(struct pt_regs *regs) +void arch_do_signal(struct pt_regs *regs) { struct ksignal ksig; diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 8493f55e1167..438fc554d48d 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) { - idtentry_state_t state; + irqentry_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; - state = idtentry_enter(regs); + state = irqentry_enter(regs); instrumentation_begin(); handle_invalid_op(regs); instrumentation_end(); - idtentry_exit(regs, state); + irqentry_exit(regs, state); } DEFINE_IDTENTRY(exc_coproc_segment_overrun) @@ -638,18 +638,18 @@ DEFINE_IDTENTRY_RAW(exc_int3) return; /* - * idtentry_enter_user() uses static_branch_{,un}likely() and therefore - * can trigger INT3, hence poke_int3_handler() must be done - * before. If the entry came from kernel mode, then use nmi_enter() - * because the INT3 could have been hit in any context including - * NMI. + * irqentry_enter_from_user_mode() uses static_branch_{,un}likely() + * and therefore can trigger INT3, hence poke_int3_handler() must + * be done before. If the entry came from kernel mode, then use + * nmi_enter() because the INT3 could have been hit in any context + * including NMI. */ if (user_mode(regs)) { - idtentry_enter_user(regs); + irqentry_enter_from_user_mode(regs); instrumentation_begin(); do_int3_user(regs); instrumentation_end(); - idtentry_exit_user(regs); + irqentry_exit_to_user_mode(regs); } else { bool irq_state = idtentry_enter_nmi(regs); instrumentation_begin(); @@ -895,13 +895,13 @@ static __always_inline void exc_debug_user(struct pt_regs *regs, */ WARN_ON_ONCE(!user_mode(regs)); - idtentry_enter_user(regs); + irqentry_enter_from_user_mode(regs); instrumentation_begin(); handle_debug(regs, dr6, true); instrumentation_end(); - idtentry_exit_user(regs); + irqentry_exit_to_user_mode(regs); } #ifdef CONFIG_X86_64 diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index b277a2db6267..fbd5bd7a945a 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -42,6 +42,7 @@ config KVM select HAVE_KVM_MSI select HAVE_KVM_CPU_RELAX_INTERCEPT select HAVE_KVM_NO_POLL + select KVM_XFER_TO_GUEST_WORK select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_VFIO select SRCU diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 13745f2a5ecd..9909375ee1fd 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -27,6 +27,7 @@ #include <linux/slab.h> #include <linux/tboot.h> #include <linux/trace_events.h> +#include <linux/entry-kvm.h> #include <asm/apic.h> #include <asm/asm.h> @@ -5373,14 +5374,12 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu) } /* - * Note, return 1 and not 0, vcpu_run() is responsible for - * morphing the pending signal into the proper return code. + * Note, return 1 and not 0, vcpu_run() will invoke + * xfer_to_guest_mode() which will create a proper return + * code. */ - if (signal_pending(current)) + if (__xfer_to_guest_mode_work_pending()) return 1; - - if (need_resched()) - schedule(); } return 1; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2dcccec48cf0..21d5e7a7ffd0 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -56,6 +56,7 @@ #include <linux/sched/stat.h> #include <linux/sched/isolation.h> #include <linux/mem_encrypt.h> +#include <linux/entry-kvm.h> #include <trace/events/kvm.h> @@ -1587,7 +1588,7 @@ EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr); bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu) { return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) || - need_resched() || signal_pending(current); + xfer_to_guest_mode_work_pending(); } EXPORT_SYMBOL_GPL(kvm_vcpu_exit_request); @@ -8681,15 +8682,11 @@ static int vcpu_run(struct kvm_vcpu *vcpu) break; } - if (signal_pending(current)) { - r = -EINTR; - vcpu->run->exit_reason = KVM_EXIT_INTR; - ++vcpu->stat.signal_exits; - break; - } - if (need_resched()) { + if (__xfer_to_guest_mode_work_pending()) { srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx); - cond_resched(); + r = xfer_to_guest_mode_handle_work(vcpu); + if (r) + return r; vcpu->srcu_idx = srcu_read_lock(&kvm->srcu); } } diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 5e41949453cc..5e5edd2ec893 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(); - idtentry_state_t state; + irqentry_state_t state; prefetchw(¤t->mm->mmap_lock); @@ -1412,11 +1412,11 @@ DEFINE_IDTENTRY_RAW_ERRORCODE(exc_page_fault) * code reenabled RCU to avoid subsequent wreckage which helps * debugability. */ - state = idtentry_enter(regs); + state = irqentry_enter(regs); instrumentation_begin(); handle_page_fault(regs, error_code, address); instrumentation_end(); - idtentry_exit(regs, state); + irqentry_exit(regs, state); } |