From mboxrd@z Thu Jan 1 00:00:00 1970 From: PGNet Dev Subject: Re: fyi, Xen's EFI workarounds (/mapbs & efi=no-rs) on SuperMicro hardware; fixes solve 1/2 problems & SM responds that can't/won't fix their firmware Date: Mon, 7 Dec 2015 06:48:27 -0800 Message-ID: <56659C3B.7090107@gmail.com> References: <56621EBF.2000301@gmail.com> <20151205180537.GA8112@char.us.oracle.com> <56632DB7.1090503@gmail.com> <56634F20.5090801@gmail.com> <20151207142012.GB22814@char.us.oracle.com> Reply-To: PGNet Dev Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20151207142012.GB22814@char.us.oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: konrad.wilk@oracle.com Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 12/07/2015 06:20 AM, Konrad Rzeszutek Wilk wrote: > However I am wondering - why are you using '/mapbs' ? What did it > help? (The combination of 'efi=no-rs' means you are in effect not > using _any_ EFI operations - so doing /mapbs is not needed). I used /mapbs because it was suggested in #irc by a dev (IIUC) @citrix to do exactly that in response to the crash. What it helped is that it cured the crash. I switched to using efi=no-rs _instead_ of /mapbs because it was recommended by a Xen dev that I do so, having called into question the robustness of /mapbs as a fix, calling it 'quite ugly'. Using just efi=no-rs also cures the crash, with the additional removal of a non-fatal acpi error. I'm now using more than just /mapbs -- specifically, adding efi=no-rs and reboot=acpi -- for, admittedly, no good reason other than you'd suggested I do so, above. I'll see what I can manage with the patch you've provided. First, tho, I need to reread all the various commentary, as I've completely lost track of what the functions and benefits of any one option, or combo thereof, are ...