Commit 63ab25eb authored by Mike Frysinger's avatar Mike Frysinger Committed by Linus Torvalds
Browse files

kgdbts: unify/generalize gdb breakpoint adjustment 



The Blackfin arch, like the x86 arch, needs to adjust the PC manually
after a breakpoint is hit as normally this is handled by the remote gdb.
However, rather than starting another arch ifdef mess, create a common
GDB_ADJUSTS_BREAK_OFFSET define for any arch to opt-in via their kgdb.h.

Signed-off-by: default avatarMike Frysinger <vapier@gentoo.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: default avatarPaul Mundt <lethal@linux-sh.org>
Acked-by: default avatarDongdong Deng <dongdong.deng@windriver.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 3cea45c6

arch/blackfin/include/asm/kgdb.h

+1 −0
Original line number Diff line number Diff line
@@ -108,6 +108,7 @@ static inline void arch_kgdb_breakpoint(void) 
#else

# define CACHE_FLUSH_IS_SAFE	1

#endif

#define GDB_ADJUSTS_BREAK_OFFSET

#define HW_INST_WATCHPOINT_NUM	6

#define HW_WATCHPOINT_NUM	8

#define TYPE_INST_WATCHPOINT	0

arch/sh/include/asm/kgdb.h

+1 −0
Original line number Diff line number Diff line
@@ -34,5 +34,6 @@ static inline void arch_kgdb_breakpoint(void) 


#define CACHE_FLUSH_IS_SAFE	1

#define BREAK_INSTR_SIZE	2

#define GDB_ADJUSTS_BREAK_OFFSET



#endif /* __ASM_SH_KGDB_H */

arch/x86/include/asm/kgdb.h

+1 −0
Original line number Diff line number Diff line
@@ -77,6 +77,7 @@ static inline void arch_kgdb_breakpoint(void) 
}

#define BREAK_INSTR_SIZE	1

#define CACHE_FLUSH_IS_SAFE	1

#define GDB_ADJUSTS_BREAK_OFFSET



extern int kgdb_ll_trap(int cmd, const char *str,

			struct pt_regs *regs, long err, int trap, int sig);

drivers/misc/kgdbts.c

+11 −18
Original line number Diff line number Diff line
@@ -285,33 +285,26 @@ static void hw_break_val_write(void) 
static int check_and_rewind_pc(char *put_str, char *arg)

{

	unsigned long addr = lookup_addr(arg);

	unsigned long ip;

	int offset = 0;



	kgdb_hex2mem(&put_str[1], (char *)kgdbts_gdb_regs,

		 NUMREGBYTES);

	gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);

	v2printk("Stopped at IP: %lx\n", instruction_pointer(&kgdbts_regs));

#ifdef CONFIG_X86

	/* On x86 a breakpoint stop requires it to be decremented */

	if (addr + 1 == kgdbts_regs.ip)

		offset = -1;

#elif defined(CONFIG_SUPERH)

	/* On SUPERH a breakpoint stop requires it to be decremented */

	if (addr + 2 == kgdbts_regs.pc)

		offset = -2;

	ip = instruction_pointer(&kgdbts_regs);

	v2printk("Stopped at IP: %lx\n", ip);

#ifdef GDB_ADJUSTS_BREAK_OFFSET

	/* On some arches, a breakpoint stop requires it to be decremented */

	if (addr + BREAK_INSTR_SIZE == ip)

		offset = -BREAK_INSTR_SIZE;

#endif

	if (strcmp(arg, "silent") &&

		instruction_pointer(&kgdbts_regs) + offset != addr) {

	if (strcmp(arg, "silent") && ip + offset != addr) {

		eprintk("kgdbts: BP mismatch %lx expected %lx\n",

			   instruction_pointer(&kgdbts_regs) + offset, addr);

			   ip + offset, addr);

		return 1;

	}

#ifdef CONFIG_X86

	/* On x86 adjust the instruction pointer if needed */

	kgdbts_regs.ip += offset;

#elif defined(CONFIG_SUPERH)

	kgdbts_regs.pc += offset;

#endif

	/* Readjust the instruction pointer if needed */

	instruction_pointer_set(&kgdbts_regs, ip + offset);

	return 0;

}

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