Commit f6170f0a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull misc x86 updates from Ingo Molnar:
 "Misc changes:

   - Enhance #GP fault printouts by distinguishing between canonical and
     non-canonical address faults, and also add KASAN fault decoding.

   - Fix/enhance the x86 NMI handler by putting the duration check into
     a direct function call instead of an irq_work which we know to be
     broken in some cases.

   - Clean up do_general_protection() a bit"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Remove irq_work from the long duration NMI handler
  x86/traps: Cleanup do_general_protection()
  x86/kasan: Print original address on #GP
  x86/dumpstack: Introduce die_addr() for die() with #GP fault address
  x86/traps: Print address on #GP
  x86/insn-eval: Add support for 64-bit kernel mode
parents 6da49d1a 248ed510

arch/x86/include/asm/kdebug.h

+1 −0
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ enum show_regs_mode { 
};



extern void die(const char *, struct pt_regs *,long);

void die_addr(const char *str, struct pt_regs *regs, long err, long gp_addr);

extern int __must_check __die(const char *, struct pt_regs *, long);

extern void show_stack_regs(struct pt_regs *regs);

extern void __show_regs(struct pt_regs *regs, enum show_regs_mode);

arch/x86/include/asm/nmi.h

+0 −1
Original line number Diff line number Diff line
@@ -41,7 +41,6 @@ struct nmiaction { 
	struct list_head	list;

	nmi_handler_t		handler;

	u64			max_duration;

	struct irq_work		irq_work;

	unsigned long		flags;

	const char		*name;

};

arch/x86/include/asm/ptrace.h

+13 −0
Original line number Diff line number Diff line
@@ -159,6 +159,19 @@ static inline bool user_64bit_mode(struct pt_regs *regs) 
#endif

}



/*

 * Determine whether the register set came from any context that is running in

 * 64-bit mode.

 */

static inline bool any_64bit_mode(struct pt_regs *regs)

{

#ifdef CONFIG_X86_64

	return !user_mode(regs) || user_64bit_mode(regs);

#else

	return false;

#endif

}



#ifdef CONFIG_X86_64

#define current_user_stack_pointer()	current_pt_regs()->sp

#define compat_user_stack_pointer()	current_pt_regs()->sp

arch/x86/kernel/dumpstack.c

+25 −1
Original line number Diff line number Diff line
@@ -365,7 +365,7 @@ void oops_end(unsigned long flags, struct pt_regs *regs, int signr) 
}

NOKPROBE_SYMBOL(oops_end);



int __die(const char *str, struct pt_regs *regs, long err)

static void __die_header(const char *str, struct pt_regs *regs, long err)

{

	const char *pr = "";
@@ -384,7 +384,11 @@ int __die(const char *str, struct pt_regs *regs, long err) 
	       IS_ENABLED(CONFIG_KASAN)   ? " KASAN"           : "",

	       IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION) ?

	       (boot_cpu_has(X86_FEATURE_PTI) ? " PTI" : " NOPTI") : "");

}

NOKPROBE_SYMBOL(__die_header);



static int __die_body(const char *str, struct pt_regs *regs, long err)

{

	show_regs(regs);

	print_modules();
@@ -394,6 +398,13 @@ int __die(const char *str, struct pt_regs *regs, long err) 


	return 0;

}

NOKPROBE_SYMBOL(__die_body);



int __die(const char *str, struct pt_regs *regs, long err)

{

	__die_header(str, regs, err);

	return __die_body(str, regs, err);

}

NOKPROBE_SYMBOL(__die);



/*
@@ -410,6 +421,19 @@ void die(const char *str, struct pt_regs *regs, long err) 
	oops_end(flags, regs, sig);

}



void die_addr(const char *str, struct pt_regs *regs, long err, long gp_addr)

{

	unsigned long flags = oops_begin();

	int sig = SIGSEGV;



	__die_header(str, regs, err);

	if (gp_addr)

		kasan_non_canonical_hook(gp_addr);

	if (__die_body(str, regs, err))

		sig = 0;

	oops_end(flags, regs, sig);

}



void show_regs(struct pt_regs *regs)

{

	show_regs_print_info(KERN_DEFAULT);

arch/x86/kernel/nmi.c

+9 −11
Original line number Diff line number Diff line
@@ -104,18 +104,22 @@ static int __init nmi_warning_debugfs(void) 
}

fs_initcall(nmi_warning_debugfs);



static void nmi_max_handler(struct irq_work *w)

static void nmi_check_duration(struct nmiaction *action, u64 duration)

{

	struct nmiaction *a = container_of(w, struct nmiaction, irq_work);

	u64 whole_msecs = READ_ONCE(action->max_duration);

	int remainder_ns, decimal_msecs;

	u64 whole_msecs = READ_ONCE(a->max_duration);



	if (duration < nmi_longest_ns || duration < action->max_duration)

		return;



	action->max_duration = duration;



	remainder_ns = do_div(whole_msecs, (1000 * 1000));

	decimal_msecs = remainder_ns / 1000;



	printk_ratelimited(KERN_INFO

		"INFO: NMI handler (%ps) took too long to run: %lld.%03d msecs\n",

		a->handler, whole_msecs, decimal_msecs);

		action->handler, whole_msecs, decimal_msecs);

}



static int nmi_handle(unsigned int type, struct pt_regs *regs)
@@ -142,11 +146,7 @@ static int nmi_handle(unsigned int type, struct pt_regs *regs) 
		delta = sched_clock() - delta;

		trace_nmi_handler(a->handler, (int)delta, thishandled);



		if (delta < nmi_longest_ns || delta < a->max_duration)

			continue;



		a->max_duration = delta;

		irq_work_queue(&a->irq_work);

		nmi_check_duration(a, delta);

	}



	rcu_read_unlock();
@@ -164,8 +164,6 @@ int __register_nmi_handler(unsigned int type, struct nmiaction *action) 
	if (!action->handler)

		return -EINVAL;



	init_irq_work(&action->irq_work, nmi_max_handler);



	raw_spin_lock_irqsave(&desc->lock, flags);



	/*

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