[lkml]   [2012]   [Apr]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRE: [PATCH 0/2] Hyper-V disk support V3

> -----Original Message-----
> From: Alan Cox []
> Sent: Wednesday, April 18, 2012 4:13 PM
> To: KY Srinivasan
> Cc: Andy Whitcroft; Jeff Garzik;; linux-
>; 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.


K. Y
> Alan

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2012-04-18 22:37    [W:0.160 / U:0.296 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site