linux-kernel - Re: BUG: Is it a bug in Linux time() function or Linux OS calls?

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] [day] [month] [year] [list]

Message-ID: <609314.24705.qm@web7608.mail.in.yahoo.com>
Date:	Thu, 11 Mar 2010 11:40:38 +0530 (IST)
From:	Srinivas Nayak <sinu_nayak2001@...oo.co.in>
To:	john stultz <johnstul@...ibm.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: BUG: Is it a bug in Linux time() function or Linux OS calls?

Dear John,

Thanks for your answer. This is informative.

With best regards,
 
Yours sincerely,
Srinivas Nayak
 
My Home page: http://www.mathmeth.com/sn/
My Blog: http://srinivas-nayak.blogspot.com


--- On Wed, 10/3/10, john stultz <johnstul@...ibm.com> wrote:

> From: john stultz <johnstul@...ibm.com>
> Subject: Re: BUG: Is it a bug in Linux time() function or Linux OS calls?
> To: "Srinivas Nayak" <sinu_nayak2001@...oo.co.in>
> Cc: linux-kernel@...r.kernel.org
> Date: Wednesday, 10 March, 2010, 10:49 PM
> On Tue, Mar 9, 2010 at 11:59 PM,
> Srinivas Nayak
> <sinu_nayak2001@...oo.co.in>
> wrote:
> > I wrote a small program, that creates files at an
> interval of 1 minute. But the time at which the file is
> created and last written and the last modification time of
> the file as shown by ls command differs by 1 second. The
> code and the output is presented below. please let me know
> where could be the bug?
> >
> [snip]
> > Some system info:
> > ===========
> > Linux new 2.6.24-19-server #1 SMP Wed Jun 18 14:44:47
> UTC 2008 x86_64 GNU/Linux
> > Gnu C                  4.2.4
> > Linux C Library        2.7
> > binutils               2.18.0.20080103
> > util-linux             2.13.1
> > Console-tools          0.2.3
> > Sh-utils               6.10
> > ===========
> 
> Hrm. Is CONFIG_NO_HZ enabled?  If so this is a known
> issue. The
> filesystem timestamps use xtime, which is normally updated
> every HZ.
> However to reduce overhead with NO_HZ we changed the update
> to be a
> half-second, which can cause issues like what you
> describe.
> 
> The issue has since been resolved, so I'd be interested to
> hear if you
> can still reproduce it on a more recent kernel.
> 
> thanks
> -john
> 


      Your Mail works best with the New Yahoo Optimized IE8. Get it NOW! http://downloads.yahoo.com/in/internetexplorer/
--
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/