netdev - Re: [PATCH 17/15] rcuwait: Inform rcuwait_wake_up() users if a wakeup was attempted

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200320104426.GD20696@hirez.programming.kicks-ass.net>
Date:   Fri, 20 Mar 2020 11:44:26 +0100
From:   Peter Zijlstra <peterz@...radead.org>
To:     Davidlohr Bueso <dave@...olabs.net>
Cc:     tglx@...utronix.de, arnd@...db.de, balbi@...nel.org,
        bhelgaas@...gle.com, bigeasy@...utronix.de, davem@...emloft.net,
        gregkh@...uxfoundation.org, joel@...lfernandes.org,
        kurt.schwemmer@...rosemi.com, kvalo@...eaurora.org,
        linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org,
        linux-usb@...r.kernel.org, linux-wireless@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, logang@...tatee.com,
        mingo@...nel.org, mpe@...erman.id.au, netdev@...r.kernel.org,
        oleg@...hat.com, paulmck@...nel.org, rdunlap@...radead.org,
        rostedt@...dmis.org, torvalds@...ux-foundation.org,
        will@...nel.org, Davidlohr Bueso <dbueso@...e.de>
Subject: Re: [PATCH 17/15] rcuwait: Inform rcuwait_wake_up() users if a
 wakeup was attempted

On Fri, Mar 20, 2020 at 01:55:25AM -0700, Davidlohr Bueso wrote:

> diff --git a/kernel/exit.c b/kernel/exit.c
> index 6cc6cc485d07..b0bb0a8ec4b1 100644
> --- a/kernel/exit.c
> +++ b/kernel/exit.c
> @@ -234,9 +234,10 @@ void release_task(struct task_struct *p)
>  		goto repeat;
>  }
>  
> -void rcuwait_wake_up(struct rcuwait *w)
> +bool rcuwait_wake_up(struct rcuwait *w)
>  {
>  	struct task_struct *task;
> +	bool ret = false;
>  
>  	rcu_read_lock();
>  
> @@ -254,10 +255,15 @@ void rcuwait_wake_up(struct rcuwait *w)
>  	smp_mb(); /* (B) */
>  
>  	task = rcu_dereference(w->task);
> -	if (task)
> +	if (task) {
>  		wake_up_process(task);
> +	        ret = true;

		ret = wake_up_process(task); ?

> +	}
>  	rcu_read_unlock();
> +
> +	return ret;
>  }
> +EXPORT_SYMBOL_GPL(rcuwait_wake_up);