On 3/7/25 08:41, Chao Gao wrote: > The xfeatures field in struct fpu_guest is designed to track the enabled > xfeatures for guest FPUs. However, during allocation in > fpu_alloc_guest_fpstate(), gfpu->xfeatures is initialized to > fpu_user_cfg.default_features, while the corresponding > fpstate->xfeatures is set to fpu_kernel_cfg.default_features > > Correct the mismatch to avoid confusion. > > Note this mismatch does not cause any functional issues. The > gfpu->xfeatures is checked in fpu_enable_guest_xfd_features() to > verify if XFD features are already enabled: > > xfeatures &= ~guest_fpu->xfeatures; > if (!xfeatures) > return 0; > > It gets updated in fpstate_realloc() after enabling some XFD features: > > guest_fpu->xfeatures |= xfeatures; > > So, backport is not needed. I don't have any great suggestions for improving this, but I just don't seem to find this changelog compelling. I can't put my finger on it, though. I think I'd find it more convincing if you argued what the *CORRECT* value is and why rather than just arguing for consistency with a random value. I also don't get the pivot over the XFD for explaining why it is harmless. XFD isn't even used in most cases, so I'd find a justification separate from XFD more compelling.
