summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/debug-monitors.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/kernel/debug-monitors.c')
-rw-r--r--arch/arm64/kernel/debug-monitors.c48
1 files changed, 15 insertions, 33 deletions
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 91fff48d0f57..73ae90ef434c 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -46,16 +46,14 @@ static void mdscr_write(u32 mdscr)
{
unsigned long flags;
local_dbg_save(flags);
- asm volatile("msr mdscr_el1, %0" :: "r" (mdscr));
+ write_sysreg(mdscr, mdscr_el1);
local_dbg_restore(flags);
}
NOKPROBE_SYMBOL(mdscr_write);
static u32 mdscr_read(void)
{
- u32 mdscr;
- asm volatile("mrs %0, mdscr_el1" : "=r" (mdscr));
- return mdscr;
+ return read_sysreg(mdscr_el1);
}
NOKPROBE_SYMBOL(mdscr_read);
@@ -132,36 +130,18 @@ NOKPROBE_SYMBOL(disable_debug_monitors);
/*
* OS lock clearing.
*/
-static void clear_os_lock(void *unused)
+static int clear_os_lock(unsigned int cpu)
{
- asm volatile("msr oslar_el1, %0" : : "r" (0));
-}
-
-static int os_lock_notify(struct notifier_block *self,
- unsigned long action, void *data)
-{
- if ((action & ~CPU_TASKS_FROZEN) == CPU_ONLINE)
- clear_os_lock(NULL);
- return NOTIFY_OK;
+ write_sysreg(0, oslar_el1);
+ isb();
+ return 0;
}
-static struct notifier_block os_lock_nb = {
- .notifier_call = os_lock_notify,
-};
-
static int debug_monitors_init(void)
{
- cpu_notifier_register_begin();
-
- /* Clear the OS lock. */
- on_each_cpu(clear_os_lock, NULL, 1);
- isb();
-
- /* Register hotplug handler. */
- __register_cpu_notifier(&os_lock_nb);
-
- cpu_notifier_register_done();
- return 0;
+ return cpuhp_setup_state(CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING,
+ "CPUHP_AP_ARM64_DEBUG_MONITORS_STARTING",
+ clear_os_lock, NULL);
}
postcore_initcall(debug_monitors_init);
@@ -254,7 +234,7 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
return 0;
if (user_mode(regs)) {
- send_user_sigtrap(TRAP_HWBKPT);
+ send_user_sigtrap(TRAP_TRACE);
/*
* ptrace will disable single step unless explicitly
@@ -382,7 +362,7 @@ NOKPROBE_SYMBOL(aarch32_break_handler);
static int __init debug_traps_init(void)
{
hook_debug_fault_code(DBG_ESR_EVT_HWSS, single_step_handler, SIGTRAP,
- TRAP_HWBKPT, "single-step handler");
+ TRAP_TRACE, "single-step handler");
hook_debug_fault_code(DBG_ESR_EVT_BRK, brk_handler, SIGTRAP,
TRAP_BRKPT, "ptrace BRK handler");
return 0;
@@ -435,8 +415,10 @@ NOKPROBE_SYMBOL(kernel_active_single_step);
/* ptrace API */
void user_enable_single_step(struct task_struct *task)
{
- set_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP);
- set_regs_spsr_ss(task_pt_regs(task));
+ struct thread_info *ti = task_thread_info(task);
+
+ if (!test_and_set_ti_thread_flag(ti, TIF_SINGLESTEP))
+ set_regs_spsr_ss(task_pt_regs(task));
}
NOKPROBE_SYMBOL(user_enable_single_step);