2019-12-23 08:47:32

by Zong Li

Subject: [PATCH 1/2] riscv: ftrace: correct the condition logic in function graph tracer

The condition should be logical NOT to assign the hook address to parent
address. Because the return value 0 of function_graph_enter upon
success.

Fixes: e949b6db51dc (riscv/function_graph: Simplify with function_graph_enter())

Signed-off-by: Zong Li <[email protected]>
---
arch/riscv/kernel/ftrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
index b94d8db5ddcc..c40fdcdeb950 100644
--- a/arch/riscv/kernel/ftrace.c
+++ b/arch/riscv/kernel/ftrace.c
@@ -142,7 +142,7 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
*/
old = *parent;

- if (function_graph_enter(old, self_addr, frame_pointer, parent))
+ if (!function_graph_enter(old, self_addr, frame_pointer, parent))
*parent = return_hooker;
}

--
2.24.1

2020-01-04 00:15:20

by Paul Walmsley

Subject: Re: [PATCH 1/2] riscv: ftrace: correct the condition logic in function graph tracer

On Mon, 23 Dec 2019, Zong Li wrote:

> The condition should be logical NOT to assign the hook address to parent
> address. Because the return value 0 of function_graph_enter upon
> success.
>
> Fixes: e949b6db51dc (riscv/function_graph: Simplify with function_graph_enter())
>

There shouldn't be a blank line here - I've removed it in the queued
version.

> Signed-off-by: Zong Li <[email protected]>

Thanks, queued for v5.5-rc.


- Paul