On Tue, May 31, 2022 at 02:52:28PM +0100, Robin Murphy wrote: > > + break; > > + pgtable_walk_level(m, phys_to_virt(phys_addr), > > Also, obligatory reminder that pfn_valid() only means that pfn_to_page() > gets you a valid struct page. Whether that page is direct-mapped kernel > memory or not is a different matter.
Even though this is debugfs, if the operation is sketchy like that and can theortically crash the kernel the driver should test capabilities, CAP_SYS_RAWIO or something may be appropriate. I don't think we have a better cap for 'userspace may crash the kernel' Jason _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
