4:52 p.m.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git tmp
head: 13665f1f8b5d501b40b1bc8448b0a032c7f04cc2
commit: ccf8d5202e24d283ec8b98a61f7241b89437383a [12132/12184] hugetlb: remove unused
hstate in hugetlb_fault_mutex_hash()
config: x86_64-randconfig-a012-20210323 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project
a4fb88669cd98db6fef7dcac88e3ec425d40c00d)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
# install x86_64 cross compiling tool for clang build
# apt-get install binutils-x86-64-linux-gnu
#
https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git/c...
git remote add sashal-linux-stable
https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git
git fetch --no-tags sashal-linux-stable tmp
git checkout ccf8d5202e24d283ec8b98a61f7241b89437383a
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All errors (new ones prefixed by >>):
> mm/userfaultfd.c:262:40: error: use of undeclared identifier
'h'
VM_BUG_ON(dst_addr & ~huge_page_mask(h));
^
mm/userfaultfd.c:273:61: error: use of undeclared identifier 'h'
dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h));
^
mm/userfaultfd.c:300:27: error: use of undeclared identifier 'h'
pages_per_huge_page(h), true);
^
3 errors generated.
vim +/h +262 mm/userfaultfd.c
c1a4de99fada21 Andrea Arcangeli 2015-09-04 167
60d4d2d2b40e44 Mike Kravetz 2017-02-22 168 #ifdef CONFIG_HUGETLB_PAGE
60d4d2d2b40e44 Mike Kravetz 2017-02-22 169 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 170 * __mcopy_atomic processing for HUGETLB
vmas. Note that this routine is
60d4d2d2b40e44 Mike Kravetz 2017-02-22 171 * called with mmap_sem held, it will
release mmap_sem before returning.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 172 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 173 static __always_inline ssize_t
__mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 174 struct vm_area_struct
*dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 175 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 176 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 177 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 178 bool zeropage)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 179 {
1c9e8def43a345 Mike Kravetz 2017-02-22 180 int vm_alloc_shared =
dst_vma->vm_flags & VM_SHARED;
1c9e8def43a345 Mike Kravetz 2017-02-22 181 int vm_shared = dst_vma->vm_flags
& VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 182 ssize_t err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 183 pte_t *dst_pte;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 184 unsigned long src_addr, dst_addr;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 185 long copied;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 186 struct page *page;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 187 unsigned long vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 188 pgoff_t idx;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 189 u32 hash;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 190 struct address_space *mapping;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 191
60d4d2d2b40e44 Mike Kravetz 2017-02-22 192 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 193 * There is no default zero huge page
for all huge page sizes as
60d4d2d2b40e44 Mike Kravetz 2017-02-22 194 * supported by hugetlb. A PMD_SIZE
huge pages may exist as used
60d4d2d2b40e44 Mike Kravetz 2017-02-22 195 * by THP. Since we can not reliably
insert a zero page, this
60d4d2d2b40e44 Mike Kravetz 2017-02-22 196 * feature is not supported.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 197 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 198 if (zeropage) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 199 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 200 return -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 201 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 202
60d4d2d2b40e44 Mike Kravetz 2017-02-22 203 src_addr = src_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 204 dst_addr = dst_start;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 205 copied = 0;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 206 page = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 207 vma_hpagesize =
vma_kernel_pagesize(dst_vma);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 208
60d4d2d2b40e44 Mike Kravetz 2017-02-22 209 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 210 * Validate alignment based on huge page
size
60d4d2d2b40e44 Mike Kravetz 2017-02-22 211 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 212 err = -EINVAL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 213 if (dst_start & (vma_hpagesize - 1)
|| len & (vma_hpagesize - 1))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 214 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 215
60d4d2d2b40e44 Mike Kravetz 2017-02-22 216 retry:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 217 /*
60d4d2d2b40e44 Mike Kravetz 2017-02-22 218 * On routine entry dst_vma is set. If
we had to drop mmap_sem and
60d4d2d2b40e44 Mike Kravetz 2017-02-22 219 * retry, dst_vma will be set to NULL
and we must lookup again.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 220 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 221 if (!dst_vma) {
27d02568f529e9 Mike Rapoport 2017-02-24 222 err = -ENOENT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 223 dst_vma = find_vma(dst_mm, dst_start);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 224 if (!dst_vma ||
!is_vm_hugetlb_page(dst_vma))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 225 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 226 /*
29ec90660d68bb Andrea Arcangeli 2018-11-30 227 * Check the vma is registered in uffd,
this is
29ec90660d68bb Andrea Arcangeli 2018-11-30 228 * required to enforce the VM_MAYWRITE
check done at
29ec90660d68bb Andrea Arcangeli 2018-11-30 229 * uffd registration time.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 230 */
27d02568f529e9 Mike Rapoport 2017-02-24 231 if
(!dst_vma->vm_userfaultfd_ctx.ctx)
27d02568f529e9 Mike Rapoport 2017-02-24 232 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 233
60d4d2d2b40e44 Mike Kravetz 2017-02-22 234 if (dst_start < dst_vma->vm_start
||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 235 dst_start + len >
dst_vma->vm_end)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 236 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 237
27d02568f529e9 Mike Rapoport 2017-02-24 238 err = -EINVAL;
27d02568f529e9 Mike Rapoport 2017-02-24 239 if (vma_hpagesize !=
vma_kernel_pagesize(dst_vma))
27d02568f529e9 Mike Rapoport 2017-02-24 240 goto out_unlock;
27d02568f529e9 Mike Rapoport 2017-02-24 241
1c9e8def43a345 Mike Kravetz 2017-02-22 242 vm_shared = dst_vma->vm_flags &
VM_SHARED;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 243 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 244
60d4d2d2b40e44 Mike Kravetz 2017-02-22 245 if (WARN_ON(dst_addr &
(vma_hpagesize - 1) ||
60d4d2d2b40e44 Mike Kravetz 2017-02-22 246 (len - copied) & (vma_hpagesize
- 1)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 247 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 248
60d4d2d2b40e44 Mike Kravetz 2017-02-22 249 /*
1c9e8def43a345 Mike Kravetz 2017-02-22 250 * If not shared, ensure the dst_vma has
a anon_vma.
60d4d2d2b40e44 Mike Kravetz 2017-02-22 251 */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 252 err = -ENOMEM;
1c9e8def43a345 Mike Kravetz 2017-02-22 253 if (!vm_shared) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 254 if
(unlikely(anon_vma_prepare(dst_vma)))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 255 goto out_unlock;
1c9e8def43a345 Mike Kravetz 2017-02-22 256 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 257
60d4d2d2b40e44 Mike Kravetz 2017-02-22 258 while (src_addr < src_start + len) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 259 pte_t dst_pteval;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 260
60d4d2d2b40e44 Mike Kravetz 2017-02-22 261 BUG_ON(dst_addr >= dst_start +
len);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 @262 VM_BUG_ON(dst_addr &
~huge_page_mask(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 263
60d4d2d2b40e44 Mike Kravetz 2017-02-22 264 /*
ddeaab32a89f04 Mike Kravetz 2019-01-08 265 * Serialize via hugetlb_fault_mutex
60d4d2d2b40e44 Mike Kravetz 2017-02-22 266 */
b43a9990055958 Mike Kravetz 2018-12-28 267 idx = linear_page_index(dst_vma,
dst_addr);
ddeaab32a89f04 Mike Kravetz 2019-01-08 268 mapping =
dst_vma->vm_file->f_mapping;
ccf8d5202e24d2 Wei Yang 2019-11-30 269 hash =
hugetlb_fault_mutex_hash(mapping, idx);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 270
mutex_lock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 271
60d4d2d2b40e44 Mike Kravetz 2017-02-22 272 err = -ENOMEM;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 273 dst_pte = huge_pte_alloc(dst_mm,
dst_addr, huge_page_size(h));
60d4d2d2b40e44 Mike Kravetz 2017-02-22 274 if (!dst_pte) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 275
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 276 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 277 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 278
60d4d2d2b40e44 Mike Kravetz 2017-02-22 279 err = -EEXIST;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 280 dst_pteval = huge_ptep_get(dst_pte);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 281 if (!huge_pte_none(dst_pteval)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 282
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 283 goto out_unlock;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 284 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 285
60d4d2d2b40e44 Mike Kravetz 2017-02-22 286 err = hugetlb_mcopy_atomic_pte(dst_mm,
dst_pte, dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 287 dst_addr, src_addr, &page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 288
60d4d2d2b40e44 Mike Kravetz 2017-02-22 289
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
1c9e8def43a345 Mike Kravetz 2017-02-22 290 vm_alloc_shared = vm_shared;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 291
60d4d2d2b40e44 Mike Kravetz 2017-02-22 292 cond_resched();
60d4d2d2b40e44 Mike Kravetz 2017-02-22 293
9e368259ad9883 Andrea Arcangeli 2018-11-30 294 if (unlikely(err == -ENOENT)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 295 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 296 BUG_ON(!page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 297
60d4d2d2b40e44 Mike Kravetz 2017-02-22 298 err = copy_huge_page_from_user(page,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 299 (const void __user *)src_addr,
810a56b943e265 Mike Kravetz 2017-02-22 300 pages_per_huge_page(h), true);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 301 if (unlikely(err)) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 302 err = -EFAULT;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 303 goto out;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 304 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 305 down_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 306
60d4d2d2b40e44 Mike Kravetz 2017-02-22 307 dst_vma = NULL;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 308 goto retry;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 309 } else
60d4d2d2b40e44 Mike Kravetz 2017-02-22 310 BUG_ON(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 311
60d4d2d2b40e44 Mike Kravetz 2017-02-22 312 if (!err) {
60d4d2d2b40e44 Mike Kravetz 2017-02-22 313 dst_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 314 src_addr += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 315 copied += vma_hpagesize;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 316
60d4d2d2b40e44 Mike Kravetz 2017-02-22 317 if (fatal_signal_pending(current))
60d4d2d2b40e44 Mike Kravetz 2017-02-22 318 err = -EINTR;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 319 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 320 if (err)
60d4d2d2b40e44 Mike Kravetz 2017-02-22 321 break;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 322 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 323
60d4d2d2b40e44 Mike Kravetz 2017-02-22 324 out_unlock:
60d4d2d2b40e44 Mike Kravetz 2017-02-22 325 up_read(&dst_mm->mmap_sem);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 326 out:
21205bf8f77b23 Mike Kravetz 2017-02-22 327 if (page) {
21205bf8f77b23 Mike Kravetz 2017-02-22 328 /*
21205bf8f77b23 Mike Kravetz 2017-02-22 329 * We encountered an error and are
about to free a newly
1c9e8def43a345 Mike Kravetz 2017-02-22 330 * allocated huge page.
1c9e8def43a345 Mike Kravetz 2017-02-22 331 *
1c9e8def43a345 Mike Kravetz 2017-02-22 332 * Reservation handling is very subtle,
and is different for
1c9e8def43a345 Mike Kravetz 2017-02-22 333 * private and shared mappings. See
the routine
1c9e8def43a345 Mike Kravetz 2017-02-22 334 * restore_reserve_on_error for
details. Unfortunately, we
1c9e8def43a345 Mike Kravetz 2017-02-22 335 * can not call
restore_reserve_on_error now as it would
1c9e8def43a345 Mike Kravetz 2017-02-22 336 * require holding mmap_sem.
1c9e8def43a345 Mike Kravetz 2017-02-22 337 *
1c9e8def43a345 Mike Kravetz 2017-02-22 338 * If a reservation for the page
existed in the reservation
1c9e8def43a345 Mike Kravetz 2017-02-22 339 * map of a private mapping, the map
was modified to indicate
1c9e8def43a345 Mike Kravetz 2017-02-22 340 * the reservation was consumed when
the page was allocated.
1c9e8def43a345 Mike Kravetz 2017-02-22 341 * We clear the PagePrivate flag now so
that the global
21205bf8f77b23 Mike Kravetz 2017-02-22 342 * reserve count will not be
incremented in free_huge_page.
21205bf8f77b23 Mike Kravetz 2017-02-22 343 * The reservation map will still
indicate the reservation
21205bf8f77b23 Mike Kravetz 2017-02-22 344 * was consumed and possibly prevent
later page allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 345 * This is better than leaking a global
reservation. If no
1c9e8def43a345 Mike Kravetz 2017-02-22 346 * reservation existed, it is still
safe to clear PagePrivate
1c9e8def43a345 Mike Kravetz 2017-02-22 347 * as no adjustments to reservation
counts were made during
1c9e8def43a345 Mike Kravetz 2017-02-22 348 * allocation.
1c9e8def43a345 Mike Kravetz 2017-02-22 349 *
1c9e8def43a345 Mike Kravetz 2017-02-22 350 * The reservation map for shared
mappings indicates which
1c9e8def43a345 Mike Kravetz 2017-02-22 351 * pages have reservations. When a
huge page is allocated
1c9e8def43a345 Mike Kravetz 2017-02-22 352 * for an address with a reservation,
no change is made to
1c9e8def43a345 Mike Kravetz 2017-02-22 353 * the reserve map. In this case
PagePrivate will be set
1c9e8def43a345 Mike Kravetz 2017-02-22 354 * to indicate that the global
reservation count should be
1c9e8def43a345 Mike Kravetz 2017-02-22 355 * incremented when the page is freed.
This is the desired
1c9e8def43a345 Mike Kravetz 2017-02-22 356 * behavior. However, when a huge page
is allocated for an
1c9e8def43a345 Mike Kravetz 2017-02-22 357 * address without a reservation a
reservation entry is added
1c9e8def43a345 Mike Kravetz 2017-02-22 358 * to the reservation map, and
PagePrivate will not be set.
1c9e8def43a345 Mike Kravetz 2017-02-22 359 * When the page is freed, the global
reserve count will NOT
1c9e8def43a345 Mike Kravetz 2017-02-22 360 * be incremented and it will appear as
though we have leaked
1c9e8def43a345 Mike Kravetz 2017-02-22 361 * reserved page. In this case, set
PagePrivate so that the
1c9e8def43a345 Mike Kravetz 2017-02-22 362 * global reserve count will be
incremented to match the
1c9e8def43a345 Mike Kravetz 2017-02-22 363 * reservation map entry which was
created.
1c9e8def43a345 Mike Kravetz 2017-02-22 364 *
1c9e8def43a345 Mike Kravetz 2017-02-22 365 * Note that vm_alloc_shared is based
on the flags of the vma
1c9e8def43a345 Mike Kravetz 2017-02-22 366 * for which the page was originally
allocated. dst_vma could
1c9e8def43a345 Mike Kravetz 2017-02-22 367 * be different or NULL on error.
21205bf8f77b23 Mike Kravetz 2017-02-22 368 */
1c9e8def43a345 Mike Kravetz 2017-02-22 369 if (vm_alloc_shared)
1c9e8def43a345 Mike Kravetz 2017-02-22 370 SetPagePrivate(page);
1c9e8def43a345 Mike Kravetz 2017-02-22 371 else
21205bf8f77b23 Mike Kravetz 2017-02-22 372 ClearPagePrivate(page);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 373 put_page(page);
21205bf8f77b23 Mike Kravetz 2017-02-22 374 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 375 BUG_ON(copied < 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 376 BUG_ON(err > 0);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 377 BUG_ON(!copied && !err);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 378 return copied ? copied : err;
60d4d2d2b40e44 Mike Kravetz 2017-02-22 379 }
60d4d2d2b40e44 Mike Kravetz 2017-02-22 380 #else /* !CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 381 /* fail at build time if gcc attempts to
use this */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 382 extern ssize_t
__mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 383 struct vm_area_struct
*dst_vma,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 384 unsigned long dst_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 385 unsigned long src_start,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 386 unsigned long len,
60d4d2d2b40e44 Mike Kravetz 2017-02-22 387 bool zeropage);
60d4d2d2b40e44 Mike Kravetz 2017-02-22 388 #endif /* CONFIG_HUGETLB_PAGE */
60d4d2d2b40e44 Mike Kravetz 2017-02-22 389
:::::: The code at line 262 was first introduced by commit
:::::: 60d4d2d2b40e44cd36bfb6049e8d9e2055a24f8a userfaultfd: hugetlbfs: add
__mcopy_atomic_hugetlb for huge page UFFDIO_COPY
:::::: TO: Mike Kravetz <mike.kravetz(a)oracle.com>
:::::: CC: Linus Torvalds <torvalds(a)linux-foundation.org>
---
0-DAY CI Kernel Test Service, Intel Corporation
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