linux-kernel - Re: [PATCH] Powerpc 8xx CPM

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: <20120814155227.018988da@pyramind.ukuu.org.uk>
Date:	Tue, 14 Aug 2012 15:52:27 +0100
From:	Alan Cox <alan@...rguk.ukuu.org.uk>
To:	Christophe Leroy <christophe.leroy@....fr>
Cc:	Alan Cox <alan@...ux.intel.com>,
	Vitaly Bordug <vitb@...nel.crashing.org>,
	Marcelo Tosatti <marcelo@...ck.org>,
	linux-kernel@...r.kernel.org, linux-serial@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org
Subject: Re: [PATCH] Powerpc 8xx CPM_UART delay in receive

On Tue, 14 Aug 2012 16:26:28 +0200
Christophe Leroy <christophe.leroy@....fr> wrote:

> Hello,
> 
> I'm not sure who to address this Patch to either
> 
> It fixes a delay issue with CPM UART driver on Powerpc MPC8xx.
> The problem is that with the actual code, the driver waits 32 IDLE patterns before returning the received data to the upper level. It means for instance about 1 second at 300 bauds.
> This fix limits to one byte the waiting period.

Take a look how the 8250 does it - I think you want to set the value
based upon the data rate. Your patch will break it for everyone doing
high seed I/O.

Alan
--
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/