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While this isn't a problem in practice, address the concern >> nevertheless to not leave dangling breakage in case very large >> superpages would be enabled at some point. >> >> Coverity ID: 1504264 >> >> While there also address a similar issue in set_iommu_ptes_present(). >> It's not clear to me why Coverity hasn't spotted that one. >> >> Signed-off-by: Jan Beulich >> --- >> v4: New. >> >> --- a/xen/drivers/passthrough/amd/iommu_map.c >> +++ b/xen/drivers/passthrough/amd/iommu_map.c >> @@ -89,11 +89,11 @@ static unsigned int set_iommu_ptes_prese >> bool iw, bool ir) >> { >> union amd_iommu_pte *table, *pde; >> - unsigned int page_sz, flush_flags = 0; >> + unsigned long page_sz = 1UL << (PTE_PER_TABLE_SHIFT * (pde_level - 1)); > > There's an off-by-12 error somewhere here. > > Judging by it's use, it should be named mapping_frames (or similar) instead. Hmm, I think the author meant "size of the (potentially large) page in units of 4k (base) pages". That's still some form of "page size". > With that fixed, Reviewed-by: Andrew Cooper If anything there could be another patch renaming the variable; that's certainly not the goal here. But as said, I don't think the variable name is strictly wrong. And with that it also doesn't feel entirely right that I would be on the hook of renaming it. I also think that "mapping_frames" isn't much better; it would need to be something like "nr_frames_per_pte", which is starting to get longish. So for the moment thanks for the R-b, but I will only apply it once we've sorted the condition you provided it under. Jan