> -----Original Message----- > From: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Sent: Friday, August 16, 2019 5:52 AM > To: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> > Cc: sashal@xxxxxxxxxx; bhelgaas@xxxxxxxxxx; linux- > hyperv@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; KY Srinivasan > <kys@xxxxxxxxxxxxx>; Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>; > olaf@xxxxxxxxx; vkuznets <vkuznets@xxxxxxxxxx>; linux- > kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH v6,1/2] PCI: hv: Detect and fix Hyper-V PCI domain > number collision > > On Thu, Aug 15, 2019 at 05:01:37PM +0000, Haiyang Zhang wrote: > > Currently in Azure cloud, for passthrough devices, the host sets the > > device instance ID's bytes 8 - 15 to a value derived from the host > > HWID, which is the same on all devices in a VM. So, the device > > instance ID's bytes 8 and 9 provided by the host are no longer unique. > > This affects all Azure hosts since July 2018, and can cause device > > passthrough to VMs to fail because the bytes 8 and 9 are used as PCI > > domain number. Collision of domain numbers will cause the second > > device with the same domain number fail to load. > > > > In the cases of collision, we will detect and find another number that > > is not in use. > > > > Suggested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> > > Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> > > Acked-by: Sasha Levin <sashal@xxxxxxxxxx> > > I assume you will take care of backporting and sending this patch to stable > kernels given that you have not applied any tag with such request. > > I appreciate it may not be easy to define but a Fixes: tag would help. Sure, I will add a Fixes tag, and Cc stable. Usually Sasha from our team will do the stable porting in batches. Thanks, - Haiyang
