diff options
Diffstat (limited to 'kernel/entry')
| -rw-r--r-- | kernel/entry/Makefile | 2 | ||||
| -rw-r--r-- | kernel/entry/common.c | 55 | ||||
| -rw-r--r-- | kernel/entry/syscall-common.c | 8 | ||||
| -rw-r--r-- | kernel/entry/virt.c (renamed from kernel/entry/kvm.c) | 15 |
4 files changed, 44 insertions, 36 deletions
diff --git a/kernel/entry/Makefile b/kernel/entry/Makefile index 77fcd83dd663..2333d70802e4 100644 --- a/kernel/entry/Makefile +++ b/kernel/entry/Makefile @@ -14,4 +14,4 @@ CFLAGS_common.o += -fno-stack-protector obj-$(CONFIG_GENERIC_IRQ_ENTRY) += common.o obj-$(CONFIG_GENERIC_SYSCALL) += syscall-common.o syscall_user_dispatch.o -obj-$(CONFIG_KVM_XFER_TO_GUEST_WORK) += kvm.o +obj-$(CONFIG_VIRT_XFER_TO_GUEST_WORK) += virt.o diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 408d28b5179d..5c792b30c58a 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -11,19 +11,20 @@ /* Workaround to allow gradual conversion of architecture code */ void __weak arch_do_signal_or_restart(struct pt_regs *regs) { } -/** - * exit_to_user_mode_loop - do any pending work before leaving to user space - * @regs: Pointer to pt_regs on entry stack - * @ti_work: TIF work flags as read by the caller - */ -__always_inline unsigned long exit_to_user_mode_loop(struct pt_regs *regs, - unsigned long ti_work) +#ifdef CONFIG_HAVE_GENERIC_TIF_BITS +#define EXIT_TO_USER_MODE_WORK_LOOP (EXIT_TO_USER_MODE_WORK & ~_TIF_RSEQ) +#else +#define EXIT_TO_USER_MODE_WORK_LOOP (EXIT_TO_USER_MODE_WORK) +#endif + +static __always_inline unsigned long __exit_to_user_mode_loop(struct pt_regs *regs, + unsigned long ti_work) { /* * Before returning to user space ensure that all pending work * items have been completed. */ - while (ti_work & EXIT_TO_USER_MODE_WORK) { + while (ti_work & EXIT_TO_USER_MODE_WORK_LOOP) { local_irq_enable_exit_to_user(ti_work); @@ -62,17 +63,21 @@ __always_inline unsigned long exit_to_user_mode_loop(struct pt_regs *regs, return ti_work; } -noinstr void irqentry_enter_from_user_mode(struct pt_regs *regs) +/** + * exit_to_user_mode_loop - do any pending work before leaving to user space + * @regs: Pointer to pt_regs on entry stack + * @ti_work: TIF work flags as read by the caller + */ +__always_inline unsigned long exit_to_user_mode_loop(struct pt_regs *regs, + unsigned long ti_work) { - enter_from_user_mode(regs); -} + for (;;) { + ti_work = __exit_to_user_mode_loop(regs, ti_work); -noinstr void irqentry_exit_to_user_mode(struct pt_regs *regs) -{ - instrumentation_begin(); - exit_to_user_mode_prepare(regs); - instrumentation_end(); - exit_to_user_mode(); + if (likely(!rseq_exit_to_user_mode_restart(regs, ti_work))) + return ti_work; + ti_work = read_thread_flags(); + } } noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) @@ -143,6 +148,20 @@ noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs) return ret; } +/** + * arch_irqentry_exit_need_resched - Architecture specific need resched function + * + * Invoked from raw_irqentry_exit_cond_resched() to check if resched is needed. + * Defaults return true. + * + * The main purpose is to permit arch to avoid preemption of a task from an IRQ. + */ +static inline bool arch_irqentry_exit_need_resched(void); + +#ifndef arch_irqentry_exit_need_resched +static inline bool arch_irqentry_exit_need_resched(void) { return true; } +#endif + void raw_irqentry_exit_cond_resched(void) { if (!preempt_count()) { @@ -150,7 +169,7 @@ void raw_irqentry_exit_cond_resched(void) rcu_irq_exit_check_preempt(); if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) WARN_ON_ONCE(!on_thread_stack()); - if (need_resched()) + if (need_resched() && arch_irqentry_exit_need_resched()) preempt_schedule_irq(); } } diff --git a/kernel/entry/syscall-common.c b/kernel/entry/syscall-common.c index 66e6ba7fa80c..940a597ded40 100644 --- a/kernel/entry/syscall-common.c +++ b/kernel/entry/syscall-common.c @@ -63,14 +63,6 @@ long syscall_trace_enter(struct pt_regs *regs, long syscall, return ret ? : syscall; } -noinstr void syscall_enter_from_user_mode_prepare(struct pt_regs *regs) -{ - enter_from_user_mode(regs); - instrumentation_begin(); - local_irq_enable(); - instrumentation_end(); -} - /* * If SYSCALL_EMU is set, then the only reason to report is when * SINGLESTEP is set (i.e. PTRACE_SYSEMU_SINGLESTEP). This syscall diff --git a/kernel/entry/kvm.c b/kernel/entry/virt.c index 8485f63863af..c52f99249763 100644 --- a/kernel/entry/kvm.c +++ b/kernel/entry/virt.c @@ -1,17 +1,14 @@ // SPDX-License-Identifier: GPL-2.0 -#include <linux/entry-kvm.h> -#include <linux/kvm_host.h> +#include <linux/entry-virt.h> -static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) +static int xfer_to_guest_mode_work(unsigned long ti_work) { do { int ret; - if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) { - kvm_handle_signal_exit(vcpu); + if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) return -EINTR; - } if (ti_work & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) schedule(); @@ -19,7 +16,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) if (ti_work & _TIF_NOTIFY_RESUME) resume_user_mode_work(NULL); - ret = arch_xfer_to_guest_mode_handle_work(vcpu, ti_work); + ret = arch_xfer_to_guest_mode_handle_work(ti_work); if (ret) return ret; @@ -28,7 +25,7 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) return 0; } -int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu) +int xfer_to_guest_mode_handle_work(void) { unsigned long ti_work; @@ -44,6 +41,6 @@ int xfer_to_guest_mode_handle_work(struct kvm_vcpu *vcpu) if (!(ti_work & XFER_TO_GUEST_MODE_WORK)) return 0; - return xfer_to_guest_mode_work(vcpu, ti_work); + return xfer_to_guest_mode_work(ti_work); } EXPORT_SYMBOL_GPL(xfer_to_guest_mode_handle_work); |