Re: [PATCH] futex: fix dead code in attach_to_pi_owner()

From: Greg KH
Date: Thu Feb 25 2021 - 03:26:57 EST


On Mon, Feb 22, 2021 at 08:53:52PM +0800, Xiaoming Ni wrote:
> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>
> The handle_exit_race() function is defined in commit c158b461306df82
> ("futex: Cure exit race"), which never returns -EBUSY. This results
> in a small piece of dead code in the attach_to_pi_owner() function:
>
> int ret = handle_exit_race(uaddr, uval, p); /* Never return -EBUSY */
> ...
> if (ret == -EBUSY)
> *exiting = p; /* dead code */
>
> The return value -EBUSY is added to handle_exit_race() in upsteam
> commit ac31c7ff8624409 ("futex: Provide distinct return value when
> owner is exiting"). This commit was incorporated into v4.9.255, before
> the function handle_exit_race() was introduced, whitout Modify
> handle_exit_race().
>
> To fix dead code, extract the change of handle_exit_race() from
> commit ac31c7ff8624409 ("futex: Provide distinct return value when owner
> is exiting"), re-incorporated.
>
> Fixes: c158b461306df82 ("futex: Cure exit race")
> Cc: stable@xxxxxxxxxxxxxxx # 4.9.258-rc1
> Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx>
> ---
> kernel/futex.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)

What is the git commit id of this patch in Linus's tree?

Also, what kernel tree(s) is this supposed to go to?

thanks,

greg k-h