> -----Original Message----- > From: Alan Cox [mailto:alan@xxxxxxxxxxxxxxxxxxx] > Sent: Wednesday, April 18, 2012 4:13 PM > To: KY Srinivasan > Cc: Andy Whitcroft; Jeff Garzik; linux-ide@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Mike Sterling > Subject: Re: [PATCH 0/2] Hyper-V disk support V3 > > > The notion of "pass through" in Hyper-V is a little different. IDE devices can be > configured > > under either one of the supported controllers and these devices can either be > virtual disks > > (VHDs) or physical disks. In either case these will be presented to the guest as > IDE devices. > > So what ensures that by skipping it at the ATA device level we will > always find it as a VHD ? If the Hyper-V storage driver is present, then the Hyper-V storage driver will manage the root device (and other devices skipped by the ata driver). So, the check if we are running on Hyper-V is not enough to skip the device in the ata_piix driver; we need to also make sure that the Hyper-V block driver is available to handle the skipped devices. I think the correct approach here is to have a kernel (or an ata_piix module parameter) that can be set to override the skipping of the block device by the ata driver. Distros that are including the Hyper-V storage driver can set this parameter so that when running on Hyper-V, ata can skip the block device. Regards, K. Y > > Alan > > -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
