linux-kernel - Re: [PATCH] sched: idle: move need_resched check after function rcu_idle

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]

Date:	Mon, 23 Nov 2015 14:05:33 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Lianwei Wang <lianwei.wang@...il.com>
Cc:	linux-kernel@...r.kernel.org, linux-pm@...ts.linux-foundation.org,
	rjw@...ysocki.net, mingo@...hat.com
Subject: Re: [PATCH] sched: idle: move need_resched check after function
 rcu_idle_enter

On Sat, Nov 21, 2015 at 01:02:02AM -0800, Lianwei Wang wrote:
> The rcu_idle_endter may call wakeup_softirqd to set the need resched
> flag on idle process. But if we don't check it after that, then the
> cpu will enter idle state with RESCHED flag set and can not be woken
> up by wakeup/resched call anymore.

Fair enough; but which cpuidle driver did you observe that with? All the
ones I checked test for need_resched again after this.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/