linux-kernel - Re: [3.6-rc1] sched: clock counts too quickly

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: <201208042110.EFH81212.OSVOLMOtFQHJFF@I-love.SAKURA.ne.jp>
Date:	Sat, 4 Aug 2012 21:10:32 +0900
From:	Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
To:	linux-kernel@...r.kernel.org
Cc:	mingo@...hat.com, peterz@...radead.org, tglx@...utronix.de
Subject: Re: [3.6-rc1] sched: clock counts too quickly

Tetsuo Handa wrote:
> > Under unknown condition, clock starts counting up too quickly which is enough
> > to confuse hangcheck timer to print stall warning.
> I wrote a test program.

I suspected that this is a problem within adjtimex() because strace reported clock
jump at adjtimex(). But I've just hit this problem with settimeofday() alone.

---------- test program 2 start ----------
#include <sys/timex.h>

int main(int argc, char *argv[])
{
        while (1) {
                struct timeval tv;
                struct timezone tz;
                gettimeofday(&tv, &tz);
                settimeofday(&tv, &tz);
        }
        return 0;
}
---------- test program 2 end ----------

Regards.
--
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/