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charset=UTF-8 Content-Transfer-Encoding: 7bit On 16.09.2024 08:47, Juergen Gross wrote: > --- a/drivers/xen/swiotlb-xen.c > +++ b/drivers/xen/swiotlb-xen.c > @@ -78,9 +78,15 @@ static inline int range_straddles_page_boundary(phys_addr_t p, size_t size) > { > unsigned long next_bfn, xen_pfn = XEN_PFN_DOWN(p); > unsigned int i, nr_pages = XEN_PFN_UP(xen_offset_in_page(p) + size); > + phys_addr_t algn = 1ULL << (get_order(size) + PAGE_SHIFT); > > next_bfn = pfn_to_bfn(xen_pfn); > > + /* If buffer is physically aligned, ensure DMA alignment. */ > + if (IS_ALIGNED(p, algn) && > + !IS_ALIGNED(next_bfn << XEN_PAGE_SHIFT, algn)) And this shift is not at risk of losing bits on Arm LPAE? Jan