linux-kernel - Re: Very strange data loss with jsm driver

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: <20110802142353.GP8562@caffeine.csclub.uwaterloo.ca>
Date:	Tue, 2 Aug 2011 10:23:53 -0400
From:	lsorense@...lub.uwaterloo.ca (Lennart Sorensen)
To:	Lennart Sorensen <lsorense@...lub.uwaterloo.ca>
Cc:	Breno Leitao <leitao@...ux.vnet.ibm.com>,
	Alan Cox <alan@...rguk.ukuu.org.uk>,
	linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: Very strange data loss with jsm driver

On Tue, Aug 02, 2011 at 10:22:25AM -0400, Lennart Sorensen wrote:
> On Tue, Aug 02, 2011 at 11:17:52AM -0300, Breno Leitao wrote:
> > Well, I finally tested it over here, and what I found is:
> > 
> > If the line has a \r among the first 16 bytes, then the information
> > is TXed immediately. If there is no \r in the first 16 bytes, then the
> > information seems to be buffered.
> 
> Where in the driver is this happening?
> 
> > So, it seems that that the patch should ask the driver to TX the
> > information when we receive a \r or when the buffer is full. Does it
> > make sense to you ?
> 
> Not sure.  I just wonder why the data is disappearing rather than getting
> buffered somewhere.  Clearly the other serial drivers are doing that
> successfully.
> 
> I don't even know why the driver should care about the contents at all.
> Just send data when it is ready.

Also, do you have any idea how to fix the statistics that 2.6.37 broke?
/proc/tty/driver/jsm used to show TX/RX and such, and that stopped
working.  I managed to fix it on Debian's 2.6.32 kernel which has some
2.6.37 serial stuff backported, but the same fix didn't work on 3.0.0.

-- 
Len Sorensen
--
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/