On Sat, Mar 01, 2025 at 07:09:35PM +0100, Thomas Gleixner wrote: > On Sat, Mar 01 2025 at 12:02, Marc Zyngier wrote: > > - This IMMUTABLE thing serves no purpose, because you don't randomly > > plug this end-point block on any MSI controller. They come as part > > of an SoC. > > Yes and no. The problem is that the EP implementation is meant to be a > generic library and while GIC-ITS guarantees immutability of the > address/data pair after setup, there are architectures (x86, loongson, > riscv) where the base MSI controller does not and immutability is only > achieved when interrupt remapping is enabled. The latter can be disabled > at boot-time and then the EP implementation becomes a lottery across > affinity changes. > > That was my concern about this library implementation and that's why I > asked for a mechanism to ensure that the underlying irqdomain provides a > immutable address/data pair. > > So it does not matter for GIC-ITS, but in the larger picture it matters. Marc: Do you satisfy Thomans's anwser? So I can respin this series. Frank > > Thanks, > > tglx
