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Diffstat (limited to 'arch/arm64/kernel/kgdb.c')
-rw-r--r--arch/arm64/kernel/kgdb.c54
1 files changed, 41 insertions, 13 deletions
diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
index b67531a13136..e017a9493b92 100644
--- a/arch/arm64/kernel/kgdb.c
+++ b/arch/arm64/kernel/kgdb.c
@@ -19,9 +19,13 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <linux/bug.h>
#include <linux/irq.h>
#include <linux/kdebug.h>
#include <linux/kgdb.h>
+#include <linux/kprobes.h>
+#include <asm/debug-monitors.h>
+#include <asm/insn.h>
#include <asm/traps.h>
struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
@@ -58,7 +62,17 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] = {
{ "x30", 8, offsetof(struct pt_regs, regs[30])},
{ "sp", 8, offsetof(struct pt_regs, sp)},
{ "pc", 8, offsetof(struct pt_regs, pc)},
- { "pstate", 8, offsetof(struct pt_regs, pstate)},
+ /*
+ * struct pt_regs thinks PSTATE is 64-bits wide but gdb remote
+ * protocol disagrees. Therefore we must extract only the lower
+ * 32-bits. Look for the big comment in asm/kgdb.h for more
+ * detail.
+ */
+ { "pstate", 4, offsetof(struct pt_regs, pstate)
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ + 4
+#endif
+ },
{ "v0", 16, -1 },
{ "v1", 16, -1 },
{ "v2", 16, -1 },
@@ -128,6 +142,8 @@ sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
memset((char *)gdb_regs, 0, NUMREGBYTES);
thread_regs = task_pt_regs(task);
memcpy((void *)gdb_regs, (void *)thread_regs->regs, GP_REG_BYTES);
+ /* Special case for PSTATE (check comments in asm/kgdb.h for details) */
+ dbg_get_reg(33, gdb_regs + GP_REG_BYTES, thread_regs);
}
void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
@@ -218,6 +234,7 @@ static int kgdb_brk_fn(struct pt_regs *regs, unsigned int esr)
kgdb_handle_exception(1, SIGTRAP, 0, regs);
return 0;
}
+NOKPROBE_SYMBOL(kgdb_brk_fn)
static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
{
@@ -226,12 +243,14 @@ static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr)
return 0;
}
+NOKPROBE_SYMBOL(kgdb_compiled_brk_fn);
static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr)
{
kgdb_handle_exception(1, SIGTRAP, 0, regs);
return 0;
}
+NOKPROBE_SYMBOL(kgdb_step_brk_fn);
static struct break_hook kgdb_brkpt_hook = {
.esr_mask = 0xffffffff,
@@ -322,15 +341,24 @@ void kgdb_arch_exit(void)
unregister_die_notifier(&kgdb_notifier);
}
-/*
- * ARM instructions are always in LE.
- * Break instruction is encoded in LE format
- */
-struct kgdb_arch arch_kgdb_ops = {
- .gdb_bpt_instr = {
- KGDB_DYN_BRK_INS_BYTE(0),
- KGDB_DYN_BRK_INS_BYTE(1),
- KGDB_DYN_BRK_INS_BYTE(2),
- KGDB_DYN_BRK_INS_BYTE(3),
- }
-};
+struct kgdb_arch arch_kgdb_ops;
+
+int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
+{
+ int err;
+
+ BUILD_BUG_ON(AARCH64_INSN_SIZE != BREAK_INSTR_SIZE);
+
+ err = aarch64_insn_read((void *)bpt->bpt_addr, (u32 *)bpt->saved_instr);
+ if (err)
+ return err;
+
+ return aarch64_insn_write((void *)bpt->bpt_addr,
+ (u32)AARCH64_BREAK_KGDB_DYN_DBG);
+}
+
+int kgdb_arch_remove_breakpoint(struct kgdb_bkpt *bpt)
+{
+ return aarch64_insn_write((void *)bpt->bpt_addr,
+ *(u32 *)bpt->saved_instr);
+}
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