Re: [RFC PATCH] docs: Enhance documentation for iommu bypass

2024-05-23 Thread Aaron Lu
On Thu, May 23, 2024 at 08:52:35PM +0800, Aaron Lu wrote: > On Wed, May 22, 2024 at 08:34:13PM +0800, Aaron Lu wrote: > > > > I do not have Windows VM right now and will report back once I finished > > testing there. > > Tested with a Windows 10 VM and turnes out virtio pci devices always > use M

Re: [RFC PATCH] docs: Enhance documentation for iommu bypass

2024-05-23 Thread Aaron Lu
On Wed, May 22, 2024 at 08:34:13PM +0800, Aaron Lu wrote: > > I do not have Windows VM right now and will report back once I finished > testing there. Tested with a Windows 10 VM and turnes out virtio pci devices always use MSI no matter vIOMMU and bypass iommu are specified or not. So according

Re: [RFC PATCH] docs: Enhance documentation for iommu bypass

2024-05-22 Thread Aaron Lu
On Wed, May 22, 2024 at 05:28:50AM -0400, Michael S. Tsirkin wrote: > On Wed, May 22, 2024 at 03:40:08PM +0800, Aaron Lu wrote: > > When Intel vIOMMU is used and irq remapping is enabled, using > > bypass_iommu will cause following two callstacks dumped during kernel > > boot and all PCI devices at

Re: [RFC PATCH] docs: Enhance documentation for iommu bypass

2024-05-22 Thread Michael S. Tsirkin
On Wed, May 22, 2024 at 03:40:08PM +0800, Aaron Lu wrote: > When Intel vIOMMU is used and irq remapping is enabled, using > bypass_iommu will cause following two callstacks dumped during kernel > boot and all PCI devices attached to root bridge lose their MSI > capabilities and fall back to using I

[RFC PATCH] docs: Enhance documentation for iommu bypass

2024-05-22 Thread Aaron Lu
When Intel vIOMMU is used and irq remapping is enabled, using bypass_iommu will cause following two callstacks dumped during kernel boot and all PCI devices attached to root bridge lose their MSI capabilities and fall back to using IOAPIC: [0.960262] [ cut here ] [0