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: Jesper Nilsson <jesper.nilsson@axis.com>
This commit is contained in:
Jesper Nilsson 2010-08-04 17:42:43 +02:00
parent 028c1f6817
commit b4e8a1813c
2 changed files with 16 additions and 3 deletions

View file

@ -32,4 +32,10 @@ config DEBUG_NMI_OOPS
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.
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

View file

@ -7,6 +7,7 @@
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/wait.h>
#include <asm/uaccess.h>
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 */
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_errno = 0;
/* info.si_code has been set above */
info.si_addr = (void *)address;
force_sig_info(SIGSEGV, &info, tsk);
printk(KERN_NOTICE "%s (pid %d) segfaults for page "
"address %08lx at pc %08lx\n",
tsk->comm, tsk->pid, address, instruction_pointer(regs));
#endif
return;
}