Hi James, kernel test robot noticed the following build warnings: [auto build test WARNING on 4d911c7abee56771b0219a9fbf0120d06bdc9c14] url: https://github.com/intel-lab-lkp/linux/commits/James-Houghton/KVM-Add-KVM_MEM_USERFAULT-memslot-flag-and-bitmap/20241205-032516 base: 4d911c7abee56771b0219a9fbf0120d06bdc9c14 patch link: https://lore.kernel.org/r/20241204191349.1730936-2-jthoughton%40google.com patch subject: [PATCH v1 01/13] KVM: Add KVM_MEM_USERFAULT memslot flag and bitmap config: i386-buildonly-randconfig-006 (https://download.01.org/0day-ci/archive/20241205/202412052133.pTg3UAQm-lkp@xxxxxxxxx/config) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241205/202412052133.pTg3UAQm-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202412052133.pTg3UAQm-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): arch/x86/kvm/../../../virt/kvm/kvm_main.c: In function '__kvm_set_memory_region': >> arch/x86/kvm/../../../virt/kvm/kvm_main.c:2049:41: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 2049 | new->userfault_bitmap = (unsigned long *)mem->userfault_bitmap; | ^ vim +2049 arch/x86/kvm/../../../virt/kvm/kvm_main.c 1931 1932 /* 1933 * Allocate some memory and give it an address in the guest physical address 1934 * space. 1935 * 1936 * Discontiguous memory is allowed, mostly for framebuffers. 1937 * 1938 * Must be called holding kvm->slots_lock for write. 1939 */ 1940 int __kvm_set_memory_region(struct kvm *kvm, 1941 const struct kvm_userspace_memory_region2 *mem) 1942 { 1943 struct kvm_memory_slot *old, *new; 1944 struct kvm_memslots *slots; 1945 enum kvm_mr_change change; 1946 unsigned long npages; 1947 gfn_t base_gfn; 1948 int as_id, id; 1949 int r; 1950 1951 r = check_memory_region_flags(kvm, mem); 1952 if (r) 1953 return r; 1954 1955 as_id = mem->slot >> 16; 1956 id = (u16)mem->slot; 1957 1958 /* General sanity checks */ 1959 if ((mem->memory_size & (PAGE_SIZE - 1)) || 1960 (mem->memory_size != (unsigned long)mem->memory_size)) 1961 return -EINVAL; 1962 if (mem->guest_phys_addr & (PAGE_SIZE - 1)) 1963 return -EINVAL; 1964 /* We can read the guest memory with __xxx_user() later on. */ 1965 if ((mem->userspace_addr & (PAGE_SIZE - 1)) || 1966 (mem->userspace_addr != untagged_addr(mem->userspace_addr)) || 1967 !access_ok((void __user *)(unsigned long)mem->userspace_addr, 1968 mem->memory_size)) 1969 return -EINVAL; 1970 if (mem->flags & KVM_MEM_GUEST_MEMFD && 1971 (mem->guest_memfd_offset & (PAGE_SIZE - 1) || 1972 mem->guest_memfd_offset + mem->memory_size < mem->guest_memfd_offset)) 1973 return -EINVAL; 1974 if (as_id >= kvm_arch_nr_memslot_as_ids(kvm) || id >= KVM_MEM_SLOTS_NUM) 1975 return -EINVAL; 1976 if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr) 1977 return -EINVAL; 1978 if ((mem->memory_size >> PAGE_SHIFT) > KVM_MEM_MAX_NR_PAGES) 1979 return -EINVAL; 1980 1981 slots = __kvm_memslots(kvm, as_id); 1982 1983 /* 1984 * Note, the old memslot (and the pointer itself!) may be invalidated 1985 * and/or destroyed by kvm_set_memslot(). 1986 */ 1987 old = id_to_memslot(slots, id); 1988 1989 if (!mem->memory_size) { 1990 if (!old || !old->npages) 1991 return -EINVAL; 1992 1993 if (WARN_ON_ONCE(kvm->nr_memslot_pages < old->npages)) 1994 return -EIO; 1995 1996 return kvm_set_memslot(kvm, old, NULL, KVM_MR_DELETE); 1997 } 1998 1999 base_gfn = (mem->guest_phys_addr >> PAGE_SHIFT); 2000 npages = (mem->memory_size >> PAGE_SHIFT); 2001 2002 if (!old || !old->npages) { 2003 change = KVM_MR_CREATE; 2004 2005 /* 2006 * To simplify KVM internals, the total number of pages across 2007 * all memslots must fit in an unsigned long. 2008 */ 2009 if ((kvm->nr_memslot_pages + npages) < kvm->nr_memslot_pages) 2010 return -EINVAL; 2011 } else { /* Modify an existing slot. */ 2012 /* Private memslots are immutable, they can only be deleted. */ 2013 if (mem->flags & KVM_MEM_GUEST_MEMFD) 2014 return -EINVAL; 2015 if ((mem->userspace_addr != old->userspace_addr) || 2016 (npages != old->npages) || 2017 ((mem->flags ^ old->flags) & KVM_MEM_READONLY)) 2018 return -EINVAL; 2019 2020 if (base_gfn != old->base_gfn) 2021 change = KVM_MR_MOVE; 2022 else if (mem->flags != old->flags) 2023 change = KVM_MR_FLAGS_ONLY; 2024 else /* Nothing to change. */ 2025 return 0; 2026 } 2027 2028 if ((change == KVM_MR_CREATE || change == KVM_MR_MOVE) && 2029 kvm_check_memslot_overlap(slots, id, base_gfn, base_gfn + npages)) 2030 return -EEXIST; 2031 2032 /* Allocate a slot that will persist in the memslot. */ 2033 new = kzalloc(sizeof(*new), GFP_KERNEL_ACCOUNT); 2034 if (!new) 2035 return -ENOMEM; 2036 2037 new->as_id = as_id; 2038 new->id = id; 2039 new->base_gfn = base_gfn; 2040 new->npages = npages; 2041 new->flags = mem->flags; 2042 new->userspace_addr = mem->userspace_addr; 2043 if (mem->flags & KVM_MEM_GUEST_MEMFD) { 2044 r = kvm_gmem_bind(kvm, new, mem->guest_memfd, mem->guest_memfd_offset); 2045 if (r) 2046 goto out; 2047 } 2048 if (mem->flags & KVM_MEM_USERFAULT) > 2049 new->userfault_bitmap = (unsigned long *)mem->userfault_bitmap; 2050 2051 r = kvm_set_memslot(kvm, old, new, change); 2052 if (r) 2053 goto out_unbind; 2054 2055 return 0; 2056 2057 out_unbind: 2058 if (mem->flags & KVM_MEM_GUEST_MEMFD) 2059 kvm_gmem_unbind(new); 2060 out: 2061 kfree(new); 2062 return r; 2063 } 2064 EXPORT_SYMBOL_GPL(__kvm_set_memory_region); 2065 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
