Re: [PATCH v3 26/34] s390/ftrace: Unpoison ftrace_regs in kprobe_ftrace_handler()

[Heiko Carstens]

On Thu, Dec 14, 2023 at 12:24:46AM +0100, Ilya Leoshkevich wrote:
> s390 uses assembly code to initialize ftrace_regs and call
> kprobe_ftrace_handler(). Therefore, from the KMSAN's point of view,
> ftrace_regs is poisoned on kprobe_ftrace_handler() entry. This causes
> KMSAN warnings when running the ftrace testsuite.
> 
> Fix by trusting the assembly code and always unpoisoning ftrace_regs in
> kprobe_ftrace_handler().
> 
> Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>
> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> ---
>  arch/s390/kernel/ftrace.c | 2 ++
>  1 file changed, 2 insertions(+)

Acked-by: Heiko Carstens <hca@xxxxxxxxxxxxx>