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Diffstat (limited to 'arch/arm64/kernel/debug-monitors.c')
-rw-r--r--arch/arm64/kernel/debug-monitors.c47
1 files changed, 33 insertions, 14 deletions
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 4fbf3c54275c..91fff48d0f57 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -23,6 +23,7 @@
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/ptrace.h>
+#include <linux/kprobes.h>
#include <linux/stat.h>
#include <linux/uaccess.h>
@@ -48,6 +49,7 @@ static void mdscr_write(u32 mdscr)
asm volatile("msr mdscr_el1, %0" :: "r" (mdscr));
local_dbg_restore(flags);
}
+NOKPROBE_SYMBOL(mdscr_write);
static u32 mdscr_read(void)
{
@@ -55,6 +57,7 @@ static u32 mdscr_read(void)
asm volatile("mrs %0, mdscr_el1" : "=r" (mdscr));
return mdscr;
}
+NOKPROBE_SYMBOL(mdscr_read);
/*
* Allow root to disable self-hosted debug from userspace.
@@ -103,6 +106,7 @@ void enable_debug_monitors(enum dbg_active_el el)
mdscr_write(mdscr);
}
}
+NOKPROBE_SYMBOL(enable_debug_monitors);
void disable_debug_monitors(enum dbg_active_el el)
{
@@ -123,6 +127,7 @@ void disable_debug_monitors(enum dbg_active_el el)
mdscr_write(mdscr);
}
}
+NOKPROBE_SYMBOL(disable_debug_monitors);
/*
* OS lock clearing.
@@ -151,7 +156,6 @@ static int debug_monitors_init(void)
/* Clear the OS lock. */
on_each_cpu(clear_os_lock, NULL, 1);
isb();
- local_dbg_enable();
/* Register hotplug handler. */
__register_cpu_notifier(&os_lock_nb);
@@ -166,22 +170,15 @@ postcore_initcall(debug_monitors_init);
*/
static void set_regs_spsr_ss(struct pt_regs *regs)
{
- unsigned long spsr;
-
- spsr = regs->pstate;
- spsr &= ~DBG_SPSR_SS;
- spsr |= DBG_SPSR_SS;
- regs->pstate = spsr;
+ regs->pstate |= DBG_SPSR_SS;
}
+NOKPROBE_SYMBOL(set_regs_spsr_ss);
static void clear_regs_spsr_ss(struct pt_regs *regs)
{
- unsigned long spsr;
-
- spsr = regs->pstate;
- spsr &= ~DBG_SPSR_SS;
- regs->pstate = spsr;
+ regs->pstate &= ~DBG_SPSR_SS;
}
+NOKPROBE_SYMBOL(clear_regs_spsr_ss);
/* EL1 Single Step Handler hooks */
static LIST_HEAD(step_hook);
@@ -225,6 +222,7 @@ static int call_step_hook(struct pt_regs *regs, unsigned int esr)
return retval;
}
+NOKPROBE_SYMBOL(call_step_hook);
static void send_user_sigtrap(int si_code)
{
@@ -266,6 +264,10 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
*/
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;
@@ -279,6 +281,7 @@ static int single_step_handler(unsigned long addr, unsigned int esr,
return 0;
}
+NOKPROBE_SYMBOL(single_step_handler);
/*
* Breakpoint handler is re-entrant as another breakpoint can
@@ -316,19 +319,28 @@ static int call_break_hook(struct pt_regs *regs, unsigned int esr)
return fn ? fn(regs, esr) : DBG_HOOK_ERROR;
}
+NOKPROBE_SYMBOL(call_break_hook);
static int brk_handler(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
{
if (user_mode(regs)) {
send_user_sigtrap(TRAP_BRKPT);
- } else if (call_break_hook(regs, esr) != DBG_HOOK_HANDLED) {
- pr_warning("Unexpected kernel BRK exception at EL1\n");
+ }
+#ifdef CONFIG_KPROBES
+ else if ((esr & BRK64_ESR_MASK) == BRK64_ESR_KPROBES) {
+ if (kprobe_breakpoint_handler(regs, esr) != DBG_HOOK_HANDLED)
+ return -EFAULT;
+ }
+#endif
+ else if (call_break_hook(regs, esr) != DBG_HOOK_HANDLED) {
+ pr_warn("Unexpected kernel BRK exception at EL1\n");
return -EFAULT;
}
return 0;
}
+NOKPROBE_SYMBOL(brk_handler);
int aarch32_break_handler(struct pt_regs *regs)
{
@@ -365,6 +377,7 @@ int aarch32_break_handler(struct pt_regs *regs)
send_user_sigtrap(TRAP_BRKPT);
return 0;
}
+NOKPROBE_SYMBOL(aarch32_break_handler);
static int __init debug_traps_init(void)
{
@@ -386,6 +399,7 @@ void user_rewind_single_step(struct task_struct *task)
if (test_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP))
set_regs_spsr_ss(task_pt_regs(task));
}
+NOKPROBE_SYMBOL(user_rewind_single_step);
void user_fastforward_single_step(struct task_struct *task)
{
@@ -401,6 +415,7 @@ void kernel_enable_single_step(struct pt_regs *regs)
mdscr_write(mdscr_read() | DBG_MDSCR_SS);
enable_debug_monitors(DBG_ACTIVE_EL1);
}
+NOKPROBE_SYMBOL(kernel_enable_single_step);
void kernel_disable_single_step(void)
{
@@ -408,12 +423,14 @@ void kernel_disable_single_step(void)
mdscr_write(mdscr_read() & ~DBG_MDSCR_SS);
disable_debug_monitors(DBG_ACTIVE_EL1);
}
+NOKPROBE_SYMBOL(kernel_disable_single_step);
int kernel_active_single_step(void)
{
WARN_ON(!irqs_disabled());
return mdscr_read() & DBG_MDSCR_SS;
}
+NOKPROBE_SYMBOL(kernel_active_single_step);
/* ptrace API */
void user_enable_single_step(struct task_struct *task)
@@ -421,8 +438,10 @@ 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));
}
+NOKPROBE_SYMBOL(user_enable_single_step);
void user_disable_single_step(struct task_struct *task)
{
clear_ti_thread_flag(task_thread_info(task), TIF_SINGLESTEP);
}
+NOKPROBE_SYMBOL(user_disable_single_step);