x86/entry: Get rid of ist_begin/end_non_atomic() (b052df3d) · Commits · 戴 / test

arch/x86/include/asm/traps.h

+0 −2

Original line number	Diff line number	Diff line
		@@ -120,8 +120,6 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void);

		extern void ist_enter(struct pt_regs *regs);
		extern void ist_exit(struct pt_regs *regs);
		extern void ist_begin_non_atomic(struct pt_regs *regs);
		extern void ist_end_non_atomic(void);

		#ifdef CONFIG_VMAP_STACK
		void __noreturn handle_stack_overflow(const char *message,

+4 −2

Original line number	Diff line number	Diff line
		@@ -1352,13 +1352,15 @@ void notrace do_machine_check(struct pt_regs *regs, long error_code)

		/* Fault was in user mode and we need to take some action */
		if ((m.cs & 3) == 3) {
		ist_begin_non_atomic(regs);
		/* If this triggers there is no way to recover. Die hard. */
		BUG_ON(!on_thread_stack() \|\| !user_mode(regs));
		local_irq_enable();
		preempt_enable();

		if (kill_it \|\| do_memory_failure(&m))
		force_sig(SIGBUS);
		preempt_disable();
		local_irq_disable();
		ist_end_non_atomic();
		} else {
		if (!fixup_exception(regs, X86_TRAP_MC, error_code, 0))
		mce_panic("Failed kernel mode recovery", &m, msg);

+0 −37

Original line number	Diff line number	Diff line
		@@ -117,43 +117,6 @@ void ist_exit(struct pt_regs *regs)
		rcu_nmi_exit();
		}

		/**
		* ist_begin_non_atomic() - begin a non-atomic section in an IST exception
		* @regs: regs passed to the IST exception handler
		*
		* IST exception handlers normally cannot schedule. As a special
		* exception, if the exception interrupted userspace code (i.e.
		* user_mode(regs) would return true) and the exception was not
		* a double fault, it can be safe to schedule. ist_begin_non_atomic()
		* begins a non-atomic section within an ist_enter()/ist_exit() region.
		* Callers are responsible for enabling interrupts themselves inside
		* the non-atomic section, and callers must call ist_end_non_atomic()
		* before ist_exit().
		*/
		void ist_begin_non_atomic(struct pt_regs *regs)
		{
		BUG_ON(!user_mode(regs));

		/*
		* Sanity check: we need to be on the normal thread stack. This
		* will catch asm bugs and any attempt to use ist_preempt_enable
		* from double_fault.
		*/
		BUG_ON(!on_thread_stack());

		preempt_enable_no_resched();
		}

		/**
		* ist_end_non_atomic() - begin a non-atomic section in an IST exception
		*
		* Ends a non-atomic section started with ist_begin_non_atomic().
		*/
		void ist_end_non_atomic(void)
		{
		preempt_disable();
		}

		int is_valid_bugaddr(unsigned long addr)
		{
		unsigned short ud;