On Fri, Dec 17, 2021 at 10:01:35PM +0000, Fenghua Yu wrote: > The ENQCMD implicitly accesses the PASID_MSR to fill in the pasid field > of the descriptor being submitted to an accelerator. But there is no > precise (and stable across kernel changes) point at which the PASID_MSR > is updated from the value for one task to the next. > > Kernel code that uses accelerators must always use the ENQCMDS instruction > which does not access the PASID_MSR. > > Check for use of the ENQCMD instruction in the kernel and warn on its > usage. > > Signed-off-by: Fenghua Yu <fenghua...@intel.com> > Reviewed-by: Tony Luck <tony.l...@intel.com> > --- > v2: > - Simplify handling ENQCMD (PeterZ and Josh)
Acked-by: Josh Poimboeuf <jpoim...@redhat.com> -- Josh _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
