diff options
Diffstat (limited to 'arch/arm64/kernel/hw_breakpoint.c')
| -rw-r--r-- | arch/arm64/kernel/hw_breakpoint.c | 69 |
1 files changed, 35 insertions, 34 deletions
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c index 0b727edf4104..2f5755192c2b 100644 --- a/arch/arm64/kernel/hw_breakpoint.c +++ b/arch/arm64/kernel/hw_breakpoint.c @@ -21,6 +21,7 @@ #include <asm/current.h> #include <asm/debug-monitors.h> +#include <asm/esr.h> #include <asm/hw_breakpoint.h> #include <asm/traps.h> #include <asm/cputype.h> @@ -257,7 +258,7 @@ static int hw_breakpoint_control(struct perf_event *bp, * level. */ enable_debug_monitors(dbg_el); - /* Fall through */ + fallthrough; case HW_BREAKPOINT_RESTORE: /* Setup the address register. */ write_wb_reg(val_reg, i, info->address); @@ -541,13 +542,13 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, if (hw->ctrl.len == ARM_BREAKPOINT_LEN_2) break; - /* Fallthrough */ + fallthrough; case 3: /* Allow single byte watchpoint. */ if (hw->ctrl.len == ARM_BREAKPOINT_LEN_1) break; - /* Fallthrough */ + fallthrough; default: return -EINVAL; } @@ -617,7 +618,7 @@ NOKPROBE_SYMBOL(toggle_bp_registers); /* * Debug exception handlers. */ -static int breakpoint_handler(unsigned long unused, unsigned int esr, +static int breakpoint_handler(unsigned long unused, unsigned long esr, struct pt_regs *regs) { int i, step = 0, *kernel_step; @@ -654,7 +655,7 @@ static int breakpoint_handler(unsigned long unused, unsigned int esr, perf_bp_event(bp, regs); /* Do we need to handle the stepping? */ - if (is_default_overflow_handler(bp)) + if (uses_default_overflow_handler(bp)) step = 1; unlock: rcu_read_unlock(); @@ -701,7 +702,7 @@ NOKPROBE_SYMBOL(breakpoint_handler); * addresses. There is no straight-forward way, short of disassembling the * offending instruction, to map that address back to the watchpoint. This * function computes the distance of the memory access from the watchpoint as a - * heuristic for the likelyhood that a given access triggered the watchpoint. + * heuristic for the likelihood that a given access triggered the watchpoint. * * See Section D2.10.5 "Determining the memory location that caused a Watchpoint * exception" of ARMv8 Architecture Reference Manual for details. @@ -730,7 +731,28 @@ static u64 get_distance_from_watchpoint(unsigned long addr, u64 val, return 0; } -static int watchpoint_handler(unsigned long addr, unsigned int esr, +static int watchpoint_report(struct perf_event *wp, unsigned long addr, + struct pt_regs *regs) +{ + int step = uses_default_overflow_handler(wp); + struct arch_hw_breakpoint *info = counter_arch_bp(wp); + + info->trigger = addr; + + /* + * If we triggered a user watchpoint from a uaccess routine, then + * handle the stepping ourselves since userspace really can't help + * us with this. + */ + if (!user_mode(regs) && info->ctrl.privilege == AARCH64_BREAKPOINT_EL0) + step = 1; + else + perf_bp_event(wp, regs); + + return step; +} + +static int watchpoint_handler(unsigned long addr, unsigned long esr, struct pt_regs *regs) { int i, step = 0, *kernel_step, access, closest_match = 0; @@ -739,7 +761,6 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr, u64 val; struct perf_event *wp, **slots; struct debug_info *debug_info; - struct arch_hw_breakpoint *info; struct arch_hw_breakpoint_ctrl ctrl; slots = this_cpu_ptr(wp_on_reg); @@ -759,7 +780,7 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr, * Check that the access type matches. * 0 => load, otherwise => store */ - access = (esr & AARCH64_ESR_ACCESS_MASK) ? HW_BREAKPOINT_W : + access = (esr & ESR_ELx_WNR) ? HW_BREAKPOINT_W : HW_BREAKPOINT_R; if (!(access & hw_breakpoint_type(wp))) continue; @@ -777,25 +798,13 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr, if (dist != 0) continue; - info = counter_arch_bp(wp); - info->trigger = addr; - perf_bp_event(wp, regs); - - /* Do we need to handle the stepping? */ - if (is_default_overflow_handler(wp)) - step = 1; + step = watchpoint_report(wp, addr, regs); } - if (min_dist > 0 && min_dist != -1) { - /* No exact match found. */ - wp = slots[closest_match]; - info = counter_arch_bp(wp); - info->trigger = addr; - perf_bp_event(wp, regs); - /* Do we need to handle the stepping? */ - if (is_default_overflow_handler(wp)) - step = 1; - } + /* No exact match found? */ + if (min_dist > 0 && min_dist != -1) + step = watchpoint_report(slots[closest_match], addr, regs); + rcu_read_unlock(); if (!step) @@ -965,14 +974,6 @@ static int hw_breakpoint_reset(unsigned int cpu) return 0; } -#ifdef CONFIG_CPU_PM -extern void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int)); -#else -static inline void cpu_suspend_set_dbg_restorer(int (*hw_bp_restore)(unsigned int)) -{ -} -#endif - /* * One-time initialisation. */ |