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The virtual_address_range selftest reads from the start of each mapping listed in /proc/self/maps. However not all mappings are valid to be arbitrarily accessed. For example the vvar data used for virtual clocks on x86 [vvar_vclock] can only be accessed if 1) the kernel configuration enables virtual clocks and 2) the hypervisor provided the data for it. Only the VDSO itself has the necessary information to know this. Since commite93d2521b2("x86/vdso: Split virtual clock pages into dedicated mapping") the virtual clock data was split out into its own mapping, leading to EFAULT from read() during the validation. Check for the VM_IO flag as a proxy. It is present for the VVAR mappings and MMIO ranges can be dangerous to access arbitrarily. Link: https://lkml.kernel.org/r/20250114-virtual_address_range-tests-v4-4-6fd7269934a5@linutronix.de Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202412271148.2656e485-lkp@intel.com Fixes:e93d2521b2("x86/vdso: Split virtual clock pages into dedicated mapping") Fixes:0104096498("selftests/mm: confirm VA exhaustion without reliance on correctness of mmap()") Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Suggested-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/lkml/e97c2a5d-c815-4936-a767-ac42a3220a90@redhat.com/ Acked-by: David Hildenbrand <david@redhat.com> Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Shuah Khan (Samsung OSG) <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>