From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: HPA unlock during partition scan of RAID components Date: Fri, 04 Nov 2011 22:26:37 -0400 Message-ID: <4EB49EDD.3020708@cfl.rr.com> References: <74AAB12B538EC94087A0D16AFDFC24F4045674@IRSMSX102.ger.corp.intel.com> <20111103153835.GF4417@google.com> <4EB2E4B7.7000103@cfl.rr.com> <4EB407DC.8070307@cfl.rr.com> <20111104155228.GY4417@google.com> <4EB4121A.1060102@cfl.rr.com> <20111104163207.GA4417@google.com> <4EB45467.4060605@cfl.rr.com> <20111104215025.GB4417@google.com> <4EB49191.6060609@cfl.rr.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Tejun Heo Cc: device-mapper development , Bartlomiej Zolnierkiewicz , "Hawrylewicz Czarnowski, Przemyslaw" List-Id: dm-devel.ids -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/04/2011 09:43 PM, Tejun Heo wrote: > Yes, it would break under windows and it does. Get a motherboard > which always locks HPA, do hotplug, create filesystem filling the > full disk and reboot. BIOS doesn't have a reliable way of > determining whether the disk is "unformatted" or not. Some try to > scan dos partition table but filesystem may be created on the whole > device or software raid could be using the whole drive. There is no > reliable way to tell. Some BIOSen may try to do HPA locking after > hotplug using ACPI _GTF which in theory can work but in practice > many motherboards either don't implement them or are horridly > broken. So, yeah, it isn't too difficult to break whether the os is > windows or linux. Well if it breaks under Windows, then we can't be faulted for having the same results now can we? > The only argument against unlocking by default and providing both > sizes is that some BIOSen may act incorrectly after soft reset, > which seems acceptable provided there's an override to disable the > automatic unlocking. The other argument is that unlocking by default trashes whatever data the bios was trying to hide in the HPA, and deviates from the behavior of Windows. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk60nt0ACgkQJ4UciIs+XuIdkACfVPbcO/Tl0bJ2g/wEb2HQ6Gpl 0u4AoL67GnVVZZgW98tGElJtYpNENXaU =bxzR -----END PGP SIGNATURE-----