From mboxrd@z Thu Jan 1 00:00:00 1970 From: Halim Issa Subject: Re: sd incorrectly reports write cache disabled on cache-capable drives/controllers Date: Fri, 25 Jan 2008 22:28:22 +0100 Message-ID: <200801252228.22659.yallaone@gmail.com> References: <200801252159.20858.yallaone@gmail.com> <1201295720.3119.51.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from fg-out-1718.google.com ([72.14.220.158]:57715 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755575AbYAYV2a (ORCPT ); Fri, 25 Jan 2008 16:28:30 -0500 Received: by fg-out-1718.google.com with SMTP id e21so780972fga.17 for ; Fri, 25 Jan 2008 13:28:29 -0800 (PST) In-Reply-To: <1201295720.3119.51.camel@localhost.localdomain> Content-Disposition: inline Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: linux-scsi@vger.kernel.org Thank you so much for the quick reply - I risk asking one follow-up question. On Friday 25 January 2008 22:15:20 James Bottomley wrote: > The "cache" hear would be referring to the RAID controller cache, not > the disk cache. Likewise DPO and FUA refer to what the RAID controller > can support, not the disk. Would it be safe to assume that the problem thus lies within the mptfusion driver, since a) the LSI Logic controller in question does indeed have hardware cache capabilities; and b) an older kernel version as well as Windows Server, correctly loads with the correct cache parameters at boot? What would be the correct path forward to trouble-shoot this further in order to get the driver to utilize the maximum hardware capabilities in the generic kernel.org kernels? Thanks again, and I apologize in advance if my questions are too basic for this list.