linux-kernel - do_schedule_next_timer && si_overrun (Was: [PATCH] posix-timers: Do not modify an already queued timer signal)

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, 21 Jul 2008 19:40:06 +0400
From:	Oleg Nesterov <oleg@...sign.ru>
To:	Roland McGrath <roland@...hat.com>
Cc:	Mark McLoughlin <markmc@...hat.com>, linux-kernel@...r.kernel.org,
	kvm@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>
Subject: do_schedule_next_timer && si_overrun (Was: [PATCH] posix-timers: Do not modify an already queued timer signal)

On 07/21, Oleg Nesterov wrote:
>
> On 07/20, Roland McGrath wrote:
> >
> > You do need to clear si_overrun there to be correct in the usual case
> > (not already queued).
>
> Indeed, I missed that. Can't we do this in send_sigqueue() ?

The more I look at the code, the more I'm getting confused...

Suppose that posix_timer_event()->send_sigqueue() increments info.si_overrun.
But (in general) it is not reported to the user-space, do_schedule_next_timer()
does:

	info->si_overrun = timr->it_overrun_last;

shouldn't it do

	info->si_overrun += timr->it_overrun_last;

instead?

Oleg.

--
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/