linux-kernel - Re: How to determine whether a file was opened O

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:	Tue, 29 Aug 2006 11:15:58 +0200 (CEST)
From:	Böszörményi Zoltán <zboszor@...aweb.hu>
To:	"Helge Hafting" <helge.hafting@...el.hist.no>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: How to determine whether a file was opened O_DIRECT?

> BĂśszĂśrmĂŠnyi ZoltĂĄn wrote:
>> Hi,
>>
>> I would like to run some diagnostics on a database
>> process and I would like to know what flags it used
>> for opening its files. Is there any way to get this info?
>>
>> Thanks in advance,
>> ZoltĂĄn BĂśszĂśrmĂŠnyi
>>
> 1. Look at the source code for the database - if you have it.

Unfortunately not.

> 2. Run your database under strace, then search the voluminous
>     output for "open" calls and look at the flags.

I can't do that, it's a production machine. But ...

> 3. Patch your kernel to "printk" information whenever
>     someone opens with O_DIRECT.

... this should have been obvious. :-) Thanks.

I just thought a command like fuser
may already exists to give me this info.
Or something under /proc/PID/fd.

>
> Helge Hafting
>

-
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/