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>
diff --git a/arch/cris/Kconfig.debug b/arch/cris/Kconfig.debug
index 0a1d62a..0b9a630 100644
--- a/arch/cris/Kconfig.debug
+++ b/arch/cris/Kconfig.debug
@@ -32,4 +32,10 @@
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
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c
index a2b4c0b..7705cd7 100644
--- a/arch/cris/mm/fault.c
+++ b/arch/cris/mm/fault.c
@@ -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 @@
/* 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;
}