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authorGuo Ren <guoren@linux.alibaba.com>2020-04-01 04:17:02 +0300
committerGuo Ren <guoren@linux.alibaba.com>2020-04-03 06:14:17 +0300
commit33e53ae1ce413a081254e686d9b27cc1b3585e2f (patch)
treedd6ddbf5a1707f1d0351143cedc00147a465abf4 /arch/csky/kernel/traps.c
parent000591f1ca3312d9a29e15a9e3fe5c4171f75586 (diff)
downloadlinux-33e53ae1ce413a081254e686d9b27cc1b3585e2f.tar.xz
csky: Add kprobes supported
This patch enable kprobes, kretprobes, ftrace interface. It utilized software breakpoint and single step debug exceptions, instructions simulation on csky. We use USR_BKPT replace origin instruction, and the kprobe handler prepares an excutable memory slot for out-of-line execution with a copy of the original instruction being probed. Most of instructions could be executed by single-step, but some instructions need origin pc value to execute and we need software simulate these instructions. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'arch/csky/kernel/traps.c')
-rw-r--r--arch/csky/kernel/traps.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/csky/kernel/traps.c b/arch/csky/kernel/traps.c
index 63715cb90ee9..c6a40806977f 100644
--- a/arch/csky/kernel/traps.c
+++ b/arch/csky/kernel/traps.c
@@ -14,6 +14,7 @@
#include <linux/kallsyms.h>
#include <linux/rtc.h>
#include <linux/uaccess.h>
+#include <linux/kprobes.h>
#include <asm/setup.h>
#include <asm/traps.h>
@@ -109,7 +110,6 @@ void buserr(struct pt_regs *regs)
force_sig_fault(SIGSEGV, 0, (void __user *)regs->pc);
}
-#define USR_BKPT 0x1464
asmlinkage void trap_c(struct pt_regs *regs)
{
int sig;
@@ -126,11 +126,19 @@ asmlinkage void trap_c(struct pt_regs *regs)
break;
/* ptrace */
case VEC_TRACE:
+#ifdef CONFIG_KPROBES
+ if (kprobe_single_step_handler(regs))
+ return;
+#endif
info.si_code = TRAP_TRACE;
sig = SIGTRAP;
break;
case VEC_ILLEGAL:
tsk->thread.trap_no = vector;
+#ifdef CONFIG_KPROBES
+ if (kprobe_breakpoint_handler(regs))
+ return;
+#endif
die_if_kernel("Kernel mode ILLEGAL", regs, vector);
#ifndef CONFIG_CPU_NO_USER_BKPT
if (*(uint16_t *)instruction_pointer(regs) != USR_BKPT)