On Tue, Jul 14, 2026 at 09:06:56PM +0800, Zhanpeng Zhang wrote: > Allow the resctrl devices file to accept iommu_group:<id> tokens on > RISC-V and map the target resource group's closid and rmid values to > RCID and MCID. > > Record non-default assignments in an RCU-protected binding list rather > than inferring membership from hardware IDs, which may be shared. Keep a > parent reference obtained by numeric group lookup so the binding does not > keep an empty group's devices kobject active, and prune bindings after > their group becomes inactive. > > Publish an explicit UPDATING state while hardware changes. Paging-domain > attachment rejects that transient state. Static FSC=Bare transitions > preserve the current IDs so a mandatory release-domain attachment cannot > fail. After the checked group update succeeds, publish the packed IDs. A > validation failure restores the previous active state without partially > changing hardware. > > Moving an IOMMU group to the default resource group resets its hardware > state and removes the software binding. Device contexts created later for > an assigned group inherit the IDs through the RCU lookup path. > > Signed-off-by: Zhanpeng Zhang <[email protected]> [..] > diff --git a/drivers/resctrl/cbqri_iommu.c b/drivers/resctrl/cbqri_iommu.c > new file mode 100644 > index 000000000000..4086c32546bd > --- /dev/null > +++ b/drivers/resctrl/cbqri_iommu.c [..] > +#include <asm/qos.h> > + > +#define IOMMU_GROUP_TOKEN "iommu_group:"
I am wondering if maybe this should be parsed at the resctrl layer since it could be possible for RISC-V and ARM to both use the iommu_group token. I am hoping that Reinette and the MPAM developrs will add their prespectives on the the resctrl devices file and at what level the tokens should be parsed. Thanks, Drew

