Commit b4e8a181 authored by Jesper Nilsson's avatar Jesper Nilsson
Browse files

CRIS: Add config for pausing a seg-faulting process 



Put it on a wait queue, so we can attach gdb to the process
to debug it instead of just killing it.

Signed-off-by: default avatarJesper Nilsson <jesper.nilsson@axis.com>
parent 028c1f68

arch/cris/Kconfig.debug

+6 −0
Original line number Original line Diff line number Diff line
@@ -32,4 +32,10 @@ config DEBUG_NMI_OOPS 
	  If the system locks up without any debug information you can say Y

	  If the system locks up without any debug information you can say Y

	  here to make it possible to dump an OOPS with an external NMI.

	  here to make it possible to dump an OOPS with an external NMI.





config NO_SEGFAULT_TERMINATION

	bool "Keep segfaulting processes"

	help

	  Place segfaulting user mode processes on a wait queue instead of

	  delivering a terminating SIGSEGV to allow debugging with gdb.



endmenu
 
endmenu

arch/cris/mm/fault.c

+10 −3
Original line number Original line Diff line number Diff line
@@ -7,6 +7,7 @@ 
#include <linux/mm.h>

#include <linux/mm.h>

#include <linux/interrupt.h>

#include <linux/interrupt.h>

#include <linux/module.h>

#include <linux/module.h>

#include <linux/wait.h>

#include <asm/uaccess.h>

#include <asm/uaccess.h>





extern int find_fixup_code(struct pt_regs *);

extern int find_fixup_code(struct pt_regs *);
@@ -190,14 +191,20 @@ do_page_fault(unsigned long address, struct pt_regs *regs, 
	/* User mode accesses just cause a SIGSEGV */

	/* User mode accesses just cause a SIGSEGV */





	if (user_mode(regs)) {

	if (user_mode(regs)) {

		printk(KERN_NOTICE "%s (pid %d) segfaults for page "

			"address %08lx at pc %08lx\n",

			tsk->comm, tsk->pid,

			address, instruction_pointer(regs));

#ifdef CONFIG_NO_SEGFAULT_TERMINATION

		DECLARE_WAIT_QUEUE_HEAD(wq);

		wait_event_interruptible(wq, 0 == 1);

#else

		info.si_signo = SIGSEGV;

		info.si_signo = SIGSEGV;

		info.si_errno = 0;

		info.si_errno = 0;

		/* info.si_code has been set above */

		/* info.si_code has been set above */

		info.si_addr = (void *)address;

		info.si_addr = (void *)address;

		force_sig_info(SIGSEGV, &info, tsk);

		force_sig_info(SIGSEGV, &info, tsk);

		printk(KERN_NOTICE "%s (pid %d) segfaults for page "

#endif

		       "address %08lx at pc %08lx\n",

		       tsk->comm, tsk->pid, address, instruction_pointer(regs));

		return;

		return;

	}

	}