[linux-yocto] [v5.2 preempt-rt][PATCH] ptrace: Remove unmatched preempt_count() issue in ptrace_stop

[Bruce Ashfield]

On Wed, Nov 13, 2019 at 12:52 AM Yongxin Liu <yongxin.liu at windriver.com> wrote:
>
> Upstream commit 53da1d9456fe7f8 ("fix ptrace slowness") introduced
> preempt_disable() and preempt_enable_no_resched() in function
> ptrace_stop(), and they should be used together.
>
> In RT kernel, commit 500d5c546e46 ("signal: Revert ptrace preempt
> magic") reverted commit 53da1d9456fe7f8. To make Yocto RT kernel the
> same as upstream RT kernel, remove preempt_enable_no_resched(), in
> stread of adding preempt_disable().
>

merged.

Bruce

> Signed-off-by: Yongxin Liu <yongxin.liu at windriver.com>
> ---
>  kernel/signal.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 4e7dddf6b3a9..7bf4b399d307 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2243,7 +2243,6 @@ static void ptrace_stop(int exit_code, int why, int clear_code, kernel_siginfo_t
>
>                 read_unlock(&tasklist_lock);
>                 cgroup_enter_frozen();
> -               preempt_enable_no_resched();
>                 freezable_schedule();
>                 cgroup_leave_frozen(true);
>         } else {
> --
> 2.14.4
>


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