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Diffstat (limited to 'arch/arm64/kernel/hw_breakpoint.c')
-rw-r--r--arch/arm64/kernel/hw_breakpoint.c56
1 files changed, 24 insertions, 32 deletions
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index ce21aa88263f..948b73148d56 100644
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -24,6 +24,7 @@
#include <linux/cpu_pm.h>
#include <linux/errno.h>
#include <linux/hw_breakpoint.h>
+#include <linux/kprobes.h>
#include <linux/perf_event.h>
#include <linux/ptrace.h>
#include <linux/smp.h>
@@ -127,6 +128,7 @@ static u64 read_wb_reg(int reg, int n)
return val;
}
+NOKPROBE_SYMBOL(read_wb_reg);
static void write_wb_reg(int reg, int n, u64 val)
{
@@ -140,6 +142,7 @@ static void write_wb_reg(int reg, int n, u64 val)
}
isb();
}
+NOKPROBE_SYMBOL(write_wb_reg);
/*
* Convert a breakpoint privilege level to the corresponding exception
@@ -157,6 +160,7 @@ static enum dbg_active_el debug_exception_level(int privilege)
return -EINVAL;
}
}
+NOKPROBE_SYMBOL(debug_exception_level);
enum hw_breakpoint_ops {
HW_BREAKPOINT_INSTALL,
@@ -575,6 +579,7 @@ static void toggle_bp_registers(int reg, enum dbg_active_el el, int enable)
write_wb_reg(reg, i, ctrl);
}
}
+NOKPROBE_SYMBOL(toggle_bp_registers);
/*
* Debug exception handlers.
@@ -654,6 +659,7 @@ unlock:
return 0;
}
+NOKPROBE_SYMBOL(breakpoint_handler);
static int watchpoint_handler(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
@@ -756,6 +762,7 @@ unlock:
return 0;
}
+NOKPROBE_SYMBOL(watchpoint_handler);
/*
* Handle single-step exception.
@@ -813,6 +820,7 @@ int reinstall_suspended_bps(struct pt_regs *regs)
return !handled_exception;
}
+NOKPROBE_SYMBOL(reinstall_suspended_bps);
/*
* Context-switcher for restoring suspended breakpoints.
@@ -849,7 +857,7 @@ void hw_breakpoint_thread_switch(struct task_struct *next)
/*
* CPU initialisation.
*/
-static void hw_breakpoint_reset(void *unused)
+static int hw_breakpoint_reset(unsigned int cpu)
{
int i;
struct perf_event **slots;
@@ -880,28 +888,14 @@ static void hw_breakpoint_reset(void *unused)
write_wb_reg(AARCH64_DBG_REG_WVR, i, 0UL);
}
}
-}
-static int hw_breakpoint_reset_notify(struct notifier_block *self,
- unsigned long action,
- void *hcpu)
-{
- if ((action & ~CPU_TASKS_FROZEN) == CPU_ONLINE) {
- local_irq_disable();
- hw_breakpoint_reset(NULL);
- local_irq_enable();
- }
- return NOTIFY_OK;
+ return 0;
}
-static struct notifier_block hw_breakpoint_reset_nb = {
- .notifier_call = hw_breakpoint_reset_notify,
-};
-
#ifdef CONFIG_CPU_PM
-extern void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *));
+extern void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int));
#else
-static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
+static inline void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int))
{
}
#endif
@@ -911,36 +905,34 @@ static inline void cpu_suspend_set_dbg_restorer(void (*hw_bp_restore)(void *))
*/
static int __init arch_hw_breakpoint_init(void)
{
+ int ret;
+
core_num_brps = get_num_brps();
core_num_wrps = get_num_wrps();
pr_info("found %d breakpoint and %d watchpoint registers.\n",
core_num_brps, core_num_wrps);
- cpu_notifier_register_begin();
-
- /*
- * Reset the breakpoint resources. We assume that a halting
- * debugger will leave the world in a nice state for us.
- */
- smp_call_function(hw_breakpoint_reset, NULL, 1);
- hw_breakpoint_reset(NULL);
-
/* Register debug fault handlers. */
hook_debug_fault_code(DBG_ESR_EVT_HWBP, breakpoint_handler, SIGTRAP,
TRAP_HWBKPT, "hw-breakpoint handler");
hook_debug_fault_code(DBG_ESR_EVT_HWWP, watchpoint_handler, SIGTRAP,
TRAP_HWBKPT, "hw-watchpoint handler");
- /* Register hotplug notifier. */
- __register_cpu_notifier(&hw_breakpoint_reset_nb);
-
- cpu_notifier_register_done();
+ /*
+ * Reset the breakpoint resources. We assume that a halting
+ * debugger will leave the world in a nice state for us.
+ */
+ ret = cpuhp_setup_state(CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
+ "CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING",
+ hw_breakpoint_reset, NULL);
+ if (ret)
+ pr_err("failed to register CPU hotplug notifier: %d\n", ret);
/* Register cpu_suspend hw breakpoint restore hook */
cpu_suspend_set_dbg_restorer(hw_breakpoint_reset);
- return 0;
+ return ret;
}
arch_initcall(arch_hw_breakpoint_init);
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