arm64: Handle TRAP_TRACE for user mode as well

uprobe registers a handler at step_hook. So, single_step_handler now
checks for user mode as well if there is a valid hook.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Pratyush Anand 2016-11-02 14:40:43 +05:30 committed by Catalin Marinas
parent b66c9870e9
commit 3fb69640fe

View File

@ -226,6 +226,8 @@ static void send_user_sigtrap(int si_code)
static int single_step_handler(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
{
bool handler_found = false;
/*
* If we are stepping a pending breakpoint, call the hw_breakpoint
* handler first.
@ -233,7 +235,14 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
if (!reinstall_suspended_bps(regs))
return 0;
if (user_mode(regs)) {
#ifdef CONFIG_KPROBES
if (kprobe_single_step_handler(regs, esr) == DBG_HOOK_HANDLED)
handler_found = true;
#endif
if (!handler_found && call_step_hook(regs, esr) == DBG_HOOK_HANDLED)
handler_found = true;
if (!handler_found && user_mode(regs)) {
send_user_sigtrap(TRAP_TRACE);
/*
@ -243,15 +252,8 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
* to the active-not-pending state).
*/
user_rewind_single_step(current);
} else {
#ifdef CONFIG_KPROBES
if (kprobe_single_step_handler(regs, esr) == DBG_HOOK_HANDLED)
return 0;
#endif
if (call_step_hook(regs, esr) == DBG_HOOK_HANDLED)
return 0;
pr_warning("Unexpected kernel single-step exception at EL1\n");
} else if (!handler_found) {
pr_warn("Unexpected kernel single-step exception at EL1\n");
/*
* Re-enable stepping since we know that we will be
* returning to regs.