Commit 874d93d1 authored by Alexander van Heukelum's avatar Alexander van Heukelum Committed by Ingo Molnar
Browse files

x86, dumpstack: let signr=0 signal no do_exit 



Change oops_end such that signr=0 signals that do_exit
is not to be called.

Currently, each use of __die is soon followed by a call
to oops_end and 'regs' is set to NULL if oops_end is expected
not to call do_exit. Change all such pairs to set signr=0
instead. On x86_64 oops_end is used 'bare' in die_nmi; use
signr=0 instead of regs=NULL there, too.

Signed-off-by: default avatarAlexander van Heukelum <heukelum@fastmail.fm>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent b4b8f87b

arch/x86/kernel/dumpstack_32.c

+4 −3
Original line number Diff line number Diff line
@@ -318,7 +318,7 @@ void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr) 
	__raw_spin_unlock(&die_lock);

	raw_local_irq_restore(flags);



	if (!regs)

	if (!signr)

		return;



	if (in_interrupt())
@@ -371,17 +371,18 @@ int __kprobes __die(const char *str, struct pt_regs *regs, long err) 
void die(const char *str, struct pt_regs *regs, long err)

{

	unsigned long flags = oops_begin();

	int sig = SIGSEGV;



	if (die_nest_count < 3) {

		report_bug(regs->ip, regs);



		if (__die(str, regs, err))

			regs = NULL;

			sig = 0;

	} else {

		printk(KERN_EMERG "Recursive die() failure, output suppressed\n");

	}



	oops_end(flags, regs, SIGSEGV);

	oops_end(flags, regs, sig);

}



static DEFINE_SPINLOCK(nmi_print_lock);

arch/x86/kernel/dumpstack_64.c

+5 −4
Original line number Diff line number Diff line
@@ -465,7 +465,7 @@ void __kprobes oops_end(unsigned long flags, struct pt_regs *regs, int signr) 
		/* Nest count reaches zero, release the lock. */

		__raw_spin_unlock(&die_lock);

	raw_local_irq_restore(flags);

	if (!regs) {

	if (!signr) {

		oops_exit();

		return;

	}
@@ -509,13 +509,14 @@ int __kprobes __die(const char *str, struct pt_regs *regs, long err) 
void die(const char *str, struct pt_regs *regs, long err)

{

	unsigned long flags = oops_begin();

	int sig = SIGSEGV;



	if (!user_mode(regs))

		report_bug(regs->ip, regs);



	if (__die(str, regs, err))

		regs = NULL;

	oops_end(flags, regs, SIGSEGV);

		sig = 0;

	oops_end(flags, regs, sig);

}



notrace __kprobes void
@@ -539,7 +540,7 @@ die_nmi(char *str, struct pt_regs *regs, int do_panic) 
		crash_kexec(regs);

	if (do_panic || panic_on_oops)

		panic("Non maskable interrupt");

	oops_end(flags, NULL, SIGBUS);

	oops_end(flags, regs, 0);

	nmi_exit();

	local_irq_enable();

	do_exit(SIGBUS);

arch/x86/mm/fault.c

+7 −4
Original line number Diff line number Diff line
@@ -413,6 +413,7 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs, 
				 unsigned long error_code)

{

	unsigned long flags = oops_begin();

	int sig = SIGKILL;

	struct task_struct *tsk;



	printk(KERN_ALERT "%s: Corrupted page table at address %lx\n",
@@ -423,8 +424,8 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs, 
	tsk->thread.trap_no = 14;

	tsk->thread.error_code = error_code;

	if (__die("Bad pagetable", regs, error_code))

		regs = NULL;

	oops_end(flags, regs, SIGKILL);

		sig = 0;

	oops_end(flags, regs, sig);

}

#endif
@@ -590,6 +591,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code) 
	int fault;

#ifdef CONFIG_X86_64

	unsigned long flags;

	int sig;

#endif



	tsk = current;
@@ -849,11 +851,12 @@ no_context: 
	bust_spinlocks(0);

	do_exit(SIGKILL);

#else

	sig = SIGKILL;

	if (__die("Oops", regs, error_code))

		regs = NULL;

		sig = 0;

	/* Executive summary in case the body of the oops scrolled away */

	printk(KERN_EMERG "CR2: %016lx\n", address);

	oops_end(flags, regs, SIGKILL);

	oops_end(flags, regs, sig);

#endif



/*

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