Commit 7f8b7ed6 authored by Jason Wessel's avatar Jason Wessel
Browse files

kgdb: Always process the whole breakpoint list on activate or deactivate 



This patch fixes 2 edge cases in using kgdb in conjunction with gdb.

1) kgdb_deactivate_sw_breakpoints() should process the entire array of
   breakpoints.  The failure to do so results in breakpoints that you
   cannot remove, because a break point can only be removed if its
   state flag is set to BP_SET.

   The easy way to duplicate this problem is to plant a break point in
   a kernel module and then unload the kernel module.

2) kgdb_activate_sw_breakpoints() should process the entire array of
   breakpoints.  The failure to do so results in missed breakpoints
   when a breakpoint cannot be activated.

Signed-off-by: default avatarJason Wessel <jason.wessel@windriver.com>
parent d625e9c0

kernel/kgdb.c

+15 −8
Original line number Diff line number Diff line
@@ -625,7 +625,8 @@ static void kgdb_flush_swbreak_addr(unsigned long addr) 
static int kgdb_activate_sw_breakpoints(void)

{

	unsigned long addr;

	int error = 0;

	int error;

	int ret = 0;

	int i;



	for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
@@ -635,13 +636,16 @@ static int kgdb_activate_sw_breakpoints(void) 
		addr = kgdb_break[i].bpt_addr;

		error = kgdb_arch_set_breakpoint(addr,

				kgdb_break[i].saved_instr);

		if (error)

			return error;

		if (error) {

			ret = error;

			printk(KERN_INFO "KGDB: BP install failed: %lx", addr);

			continue;

		}



		kgdb_flush_swbreak_addr(addr);

		kgdb_break[i].state = BP_ACTIVE;

	}

	return 0;

	return ret;

}



static int kgdb_set_sw_break(unsigned long addr)
@@ -688,7 +692,8 @@ static int kgdb_set_sw_break(unsigned long addr) 
static int kgdb_deactivate_sw_breakpoints(void)

{

	unsigned long addr;

	int error = 0;

	int error;

	int ret = 0;

	int i;



	for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
@@ -697,13 +702,15 @@ static int kgdb_deactivate_sw_breakpoints(void) 
		addr = kgdb_break[i].bpt_addr;

		error = kgdb_arch_remove_breakpoint(addr,

					kgdb_break[i].saved_instr);

		if (error)

			return error;

		if (error) {

			printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);

			ret = error;

		}



		kgdb_flush_swbreak_addr(addr);

		kgdb_break[i].state = BP_SET;

	}

	return 0;

	return ret;

}



static int kgdb_remove_sw_break(unsigned long addr)

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