On Tue, Jun 04, 2024 at 04:25:51PM +0100, Marc Zyngier wrote: > On Mon, 03 Jun 2024 22:04:23 +0100, > Frank Li <Frank.li@xxxxxxx> wrote: > > > > iommu may share one stream id for multi-devices. but ITS MSI can't. each > > device's MSI index start from 0. It needs difference stream id for each > > device. > > That's not quite true. We go through all sort of hoops to find about > device aliasing on PCI and allow devices that translate into the same > DID to get MSIs. Could you please point me the code location? I remember I met error when I try to enable MSI for EP support one year ago. https://lore.kernel.org/imx/20221124055036.1630573-1-Frank.Li@xxxxxxx/ I remember that it is failure try to allocate more irqs with the same DID. Frank > > Of course, just like the IOMMU, you lose any form of isolation, but > you get what you pay for. Anyways, if there are one quirk in PCI system, bridge driver can detect PCI devices add/remove. it will be better if assign stream ID as need, compared with static allocate. > > M. > > -- > Without deviation from the norm, progress is not possible.
