Re: [PATCH v2 01/33] ftrace: Unpoison ftrace_regs in ftrace_ops_list_func()

[Alexander Potapenko]

On Tue, Nov 21, 2023 at 11:02 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote:
>
> Architectures use assembly code to initialize ftrace_regs and call
> ftrace_ops_list_func(). Therefore, from the KMSAN's point of view,
> ftrace_regs is poisoned on ftrace_ops_list_func entry(). This causes
> KMSAN warnings when running the ftrace testsuite.

I couldn't reproduce these warnings on x86, hope you really need this
change on s390 :)

> Fix by trusting the architecture-specific assembly code and always
> unpoisoning ftrace_regs in ftrace_ops_list_func.
>
> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>