This reverts commit fab840fc2d542fabcab903db8e03589a6702ba5f.

This commit even has the test-case to prove that the tracee
can be killed by SIGTRAP if the debugger does not remove the
breakpoints before PTRACE_DETACH.

However, this is exactly what wineserver deliberately does,
set_thread_context() calls PTRACE_ATTACH + PTRACE_DETACH just
for PTRACE_POKEUSER(DR*) in between.

So we should revert this fix and document that PTRACE_DETACH
should keep the breakpoints.

Reported-by: Felipe Contreras <felipe.contre...@gmail.com>
Signed-off-by: Oleg Nesterov <o...@redhat.com>
---
 kernel/ptrace.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 4041f57..a146ee3 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -469,7 +469,6 @@ static int ptrace_detach(struct task_struct *child, 
unsigned int data)
        /* Architecture-specific hardware disable .. */
        ptrace_disable(child);
        clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
-       flush_ptrace_hw_breakpoint(child);
 
        write_lock_irq(&tasklist_lock);
        /*
-- 
1.5.5.1


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to