From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 0A1871007D1 for ; Tue, 5 Jul 2011 16:23:05 +1000 (EST) Subject: Re: hvc_console change results in corrupt oops output From: Benjamin Herrenschmidt To: Tabi Timur-B04825 In-Reply-To: References: <20110704205738.742e56d0@kryten> <1309787787.14501.268.camel@pasglop> <20110704142429.GA2147@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Date: Tue, 05 Jul 2011 16:22:43 +1000 Message-ID: <1309846963.14501.270.camel@pasglop> Mime-Version: 1.0 Cc: "borntraeger@de.ibm.com" , Hendrik Brueckner , "linuxppc-dev@lists.ozlabs.org" , Anton Blanchard List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2011-07-05 at 04:17 +0000, Tabi Timur-B04825 wrote: > On Mon, Jul 4, 2011 at 9:24 AM, Hendrik Brueckner > wrote: > > > I will check this again for my hvc_iucv back-end. Meanwhile a found > > an old thread discussing the same issue. It covers some differences > > between console and ttys which actually does not matter for hvc-backend > > because of the shared put_chars() routine. > > > > You can read the thread on lkml.org: http://lkml.org/lkml/2009/10/15/149 > > I started that thread. After much soul searching, we came to the > conclusion that HVC is not compatible with hypervisors that return > BUSY on writes. That is a fun conclusion considering that hvc has been written for the pseries hypervisor which ... can return BUSY on writes :-) > So I threw out my HVC driver and rewrote it as a > standard console and TTY driver. That driver is waiting to be > included in the 3.1 kernel. Sucktastic. We just need to fix HVC properly. Cheers, Ben.