diff options
Diffstat (limited to 'arch/x86/kernel/hw_breakpoint.c')
-rw-r--r-- | arch/x86/kernel/hw_breakpoint.c | 58 |
1 files changed, 6 insertions, 52 deletions
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c index b98ff620ba77..03aa33b58165 100644 --- a/arch/x86/kernel/hw_breakpoint.c +++ b/arch/x86/kernel/hw_breakpoint.c @@ -442,42 +442,6 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, } /* - * Dump the debug register contents to the user. - * We can't dump our per cpu values because it - * may contain cpu wide breakpoint, something that - * doesn't belong to the current task. - * - * TODO: include non-ptrace user breakpoints (perf) - */ -void aout_dump_debugregs(struct user *dump) -{ - int i; - int dr7 = 0; - struct perf_event *bp; - struct arch_hw_breakpoint *info; - struct thread_struct *thread = ¤t->thread; - - for (i = 0; i < HBP_NUM; i++) { - bp = thread->ptrace_bps[i]; - - if (bp && !bp->attr.disabled) { - dump->u_debugreg[i] = bp->attr.bp_addr; - info = counter_arch_bp(bp); - dr7 |= encode_dr7(i, info->len, info->type); - } else { - dump->u_debugreg[i] = 0; - } - } - - dump->u_debugreg[4] = 0; - dump->u_debugreg[5] = 0; - dump->u_debugreg[6] = current->thread.debugreg6; - - dump->u_debugreg[7] = dr7; -} -EXPORT_SYMBOL_GPL(aout_dump_debugregs); - -/* * Release the user breakpoints used by ptrace */ void flush_ptrace_hw_breakpoint(struct task_struct *tsk) @@ -490,7 +454,7 @@ void flush_ptrace_hw_breakpoint(struct task_struct *tsk) t->ptrace_bps[i] = NULL; } - t->debugreg6 = 0; + t->virtual_dr6 = 0; t->ptrace_dr7 = 0; } @@ -500,7 +464,7 @@ void hw_breakpoint_restore(void) set_debugreg(__this_cpu_read(cpu_debugreg[1]), 1); set_debugreg(__this_cpu_read(cpu_debugreg[2]), 2); set_debugreg(__this_cpu_read(cpu_debugreg[3]), 3); - set_debugreg(current->thread.debugreg6, 6); + set_debugreg(DR6_RESERVED, 6); set_debugreg(__this_cpu_read(cpu_dr7), 7); } EXPORT_SYMBOL_GPL(hw_breakpoint_restore); @@ -523,10 +487,10 @@ EXPORT_SYMBOL_GPL(hw_breakpoint_restore); */ static int hw_breakpoint_handler(struct die_args *args) { - int i, cpu, rc = NOTIFY_STOP; + int i, rc = NOTIFY_STOP; struct perf_event *bp; - unsigned long dr6; unsigned long *dr6_p; + unsigned long dr6; /* The DR6 value is pointed by args->err */ dr6_p = (unsigned long *)ERR_PTR(args->err); @@ -540,14 +504,6 @@ static int hw_breakpoint_handler(struct die_args *args) if ((dr6 & DR_TRAP_BITS) == 0) return NOTIFY_DONE; - /* - * Assert that local interrupts are disabled - * Reset the DRn bits in the virtualized register value. - * The ptrace trigger routine will add in whatever is needed. - */ - current->thread.debugreg6 &= ~DR_TRAP_BITS; - cpu = get_cpu(); - /* Handle all the breakpoints that were triggered */ for (i = 0; i < HBP_NUM; ++i) { if (likely(!(dr6 & (DR_TRAP0 << i)))) @@ -561,7 +517,7 @@ static int hw_breakpoint_handler(struct die_args *args) */ rcu_read_lock(); - bp = per_cpu(bp_per_reg[i], cpu); + bp = this_cpu_read(bp_per_reg[i]); /* * Reset the 'i'th TRAP bit in dr6 to denote completion of * exception handling @@ -592,12 +548,10 @@ static int hw_breakpoint_handler(struct die_args *args) * breakpoints (to generate signals) and b) when the system has * taken exception due to multiple causes */ - if ((current->thread.debugreg6 & DR_TRAP_BITS) || + if ((current->thread.virtual_dr6 & DR_TRAP_BITS) || (dr6 & (~DR_TRAP_BITS))) rc = NOTIFY_DONE; - put_cpu(); - return rc; } |