summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/entry-common.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/kernel/entry-common.c')
-rw-r--r--arch/arm64/kernel/entry-common.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c
index be2add6b4ae3..7265bef96672 100644
--- a/arch/arm64/kernel/entry-common.c
+++ b/arch/arm64/kernel/entry-common.c
@@ -535,6 +535,24 @@ static void noinstr el1_breakpt(struct pt_regs *regs, unsigned long esr)
arm64_exit_el1_dbg(regs);
}
+static void noinstr el1_softstp(struct pt_regs *regs, unsigned long esr)
+{
+ arm64_enter_el1_dbg(regs);
+ if (!cortex_a76_erratum_1463225_debug_handler(regs)) {
+ debug_exception_enter(regs);
+ /*
+ * After handling a breakpoint, we suspend the breakpoint
+ * and use single-step to move to the next instruction.
+ * If we are stepping a suspended breakpoint there's nothing more to do:
+ * the single-step is complete.
+ */
+ if (!try_step_suspended_breakpoints(regs))
+ do_el1_softstep(esr, regs);
+ debug_exception_exit(regs);
+ }
+ arm64_exit_el1_dbg(regs);
+}
+
static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr)
{
unsigned long far = read_sysreg(far_el1);
@@ -587,6 +605,8 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs)
el1_breakpt(regs, esr);
break;
case ESR_ELx_EC_SOFTSTP_CUR:
+ el1_softstp(regs, esr);
+ break;
case ESR_ELx_EC_WATCHPT_CUR:
case ESR_ELx_EC_BRK64:
el1_dbg(regs, esr);
@@ -793,6 +813,25 @@ static void noinstr el0_breakpt(struct pt_regs *regs, unsigned long esr)
exit_to_user_mode(regs);
}
+static void noinstr el0_softstp(struct pt_regs *regs, unsigned long esr)
+{
+ if (!is_ttbr0_addr(regs->pc))
+ arm64_apply_bp_hardening();
+
+ enter_from_user_mode(regs);
+ /*
+ * After handling a breakpoint, we suspend the breakpoint
+ * and use single-step to move to the next instruction.
+ * If we are stepping a suspended breakpoint there's nothing more to do:
+ * the single-step is complete.
+ */
+ if (!try_step_suspended_breakpoints(regs)) {
+ local_daif_restore(DAIF_PROCCTX);
+ do_el0_softstep(esr, regs);
+ }
+ exit_to_user_mode(regs);
+}
+
static void noinstr el0_dbg(struct pt_regs *regs, unsigned long esr)
{
/* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */
@@ -875,6 +914,8 @@ asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs)
el0_breakpt(regs, esr);
break;
case ESR_ELx_EC_SOFTSTP_LOW:
+ el0_softstp(regs, esr);
+ break;
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BRK64:
el0_dbg(regs, esr);
@@ -997,6 +1038,8 @@ asmlinkage void noinstr el0t_32_sync_handler(struct pt_regs *regs)
el0_breakpt(regs, esr);
break;
case ESR_ELx_EC_SOFTSTP_LOW:
+ el0_softstp(regs, esr);
+ break;
case ESR_ELx_EC_WATCHPT_LOW:
case ESR_ELx_EC_BKPT32:
el0_dbg(regs, esr);