powerpc: Add PTRACE_SINGLEBLOCK support
Reworked by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds block-step support on powerpc, including a PTRACE_SINGLEBLOCK
request for ptrace.
The BookE implementation is tweaked to fire a single step after a
block step in order to mimmic the server behaviour.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 3635be6..9fa2c7d 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -704,15 +704,34 @@
if (regs != NULL) {
#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
+ task->thread.dbcr0 &= ~DBCR0_BT;
task->thread.dbcr0 |= DBCR0_IDM | DBCR0_IC;
regs->msr |= MSR_DE;
#else
+ regs->msr &= ~MSR_BE;
regs->msr |= MSR_SE;
#endif
}
set_tsk_thread_flag(task, TIF_SINGLESTEP);
}
+void user_enable_block_step(struct task_struct *task)
+{
+ struct pt_regs *regs = task->thread.regs;
+
+ if (regs != NULL) {
+#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
+ task->thread.dbcr0 &= ~DBCR0_IC;
+ task->thread.dbcr0 = DBCR0_IDM | DBCR0_BT;
+ regs->msr |= MSR_DE;
+#else
+ regs->msr &= ~MSR_SE;
+ regs->msr |= MSR_BE;
+#endif
+ }
+ set_tsk_thread_flag(task, TIF_SINGLESTEP);
+}
+
void user_disable_single_step(struct task_struct *task)
{
struct pt_regs *regs = task->thread.regs;
@@ -726,10 +745,10 @@
if (regs != NULL) {
#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
- task->thread.dbcr0 &= ~(DBCR0_IC | DBCR0_IDM);
+ task->thread.dbcr0 &= ~(DBCR0_IC | DBCR0_BT | DBCR0_IDM);
regs->msr &= ~MSR_DE;
#else
- regs->msr &= ~MSR_SE;
+ regs->msr &= ~(MSR_SE | MSR_BE);
#endif
}
clear_tsk_thread_flag(task, TIF_SINGLESTEP);