Hi Renzo, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.2-rc2 next-20190524] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Renzo-Davoli/eventfd-new-tag-EFD_VPOLL-generate-epoll-events/20190527-023620 reproduce: # apt-get install sparse # sparse version: v0.6.1-rc1-7-g2b96cd8-dirty make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> sparse warnings: (new ones prefixed by >>) >> fs/eventfd.c:321:27: sparse: sparse: restricted __poll_t degrades to integer >> fs/eventfd.c:321:16: sparse: sparse: incorrect type in assignment (different base types) @@ expected restricted __poll_t [usertype] events @@ got poll_t [usertype] events @@ >> fs/eventfd.c:321:16: sparse: expected restricted __poll_t [usertype] events >> fs/eventfd.c:321:16: sparse: got unsigned long long fs/eventfd.c:357:25: sparse: sparse: restricted __poll_t degrades to integer >> fs/eventfd.c:359:27: sparse: sparse: cast from restricted __poll_t fs/eventfd.c:367:44: sparse: sparse: restricted __poll_t degrades to integer >> fs/eventfd.c:375:17: sparse: sparse: cast to restricted __poll_t >> fs/eventfd.c:512:28: sparse: sparse: invalid assignment: &= >> fs/eventfd.c:512:28: sparse: left side has type unsigned long long >> fs/eventfd.c:512:28: sparse: right side has type restricted __poll_t vim +321 fs/eventfd.c 310 311 static __poll_t eventfd_vpoll_poll(struct file *file, poll_table *wait) 312 { 313 struct eventfd_ctx *ctx = file->private_data; 314 __poll_t events = 0; 315 u64 count; 316 317 poll_wait(file, &ctx->wqh, wait); 318 319 count = READ_ONCE(ctx->count); 320 > 321 events = (count & EPOLLALLMASK); 322 323 return events; 324 } 325 326 static ssize_t eventfd_vpoll_read(struct file *file, char __user *buf, 327 size_t count, loff_t *ppos) 328 { 329 struct eventfd_ctx *ctx = file->private_data; 330 ssize_t res; 331 __u64 ucnt = 0; 332 333 if (count < sizeof(ucnt)) 334 return -EINVAL; 335 res = sizeof(ucnt); 336 ucnt = READ_ONCE(ctx->count); 337 if (put_user(ucnt, (__u64 __user *)buf)) 338 return -EFAULT; 339 340 return res; 341 } 342 343 static ssize_t eventfd_vpoll_write(struct file *file, const char __user *buf, 344 size_t count, loff_t *ppos) 345 { 346 struct eventfd_ctx *ctx = file->private_data; 347 ssize_t res; 348 __u64 ucnt; 349 __u32 events; 350 351 if (count < sizeof(ucnt)) 352 return -EINVAL; 353 if (copy_from_user(&ucnt, buf, sizeof(ucnt))) 354 return -EFAULT; 355 spin_lock_irq(&ctx->wqh.lock); 356 357 events = ucnt & EPOLLALLMASK; 358 res = sizeof(ucnt); > 359 switch (ucnt & ~((__u64)EPOLLALLMASK)) { 360 case EFD_VPOLL_ADDEVENTS: 361 ctx->count |= events; 362 break; 363 case EFD_VPOLL_DELEVENTS: 364 ctx->count &= ~(events); 365 break; 366 case EFD_VPOLL_MODEVENTS: 367 ctx->count = (ctx->count & ~EPOLLALLMASK) | events; 368 break; 369 default: 370 res = -EINVAL; 371 } 372 373 /* wake up waiting threads */ 374 if (res >= 0 && waitqueue_active(&ctx->wqh)) > 375 wake_up_locked_poll(&ctx->wqh, res); 376 377 spin_unlock_irq(&ctx->wqh.lock); 378 379 return res; 380 381 } 382 383 #ifdef CONFIG_PROC_FS 384 static void eventfd_show_fdinfo(struct seq_file *m, struct file *f) 385 { 386 struct eventfd_ctx *ctx = f->private_data; 387 388 spin_lock_irq(&ctx->wqh.lock); 389 seq_printf(m, "eventfd-count: %16llx\n", 390 (unsigned long long)ctx->count); 391 spin_unlock_irq(&ctx->wqh.lock); 392 seq_printf(m, "eventfd-id: %d\n", ctx->id); 393 } 394 #endif 395 396 static const struct file_operations eventfd_fops = { 397 #ifdef CONFIG_PROC_FS 398 .show_fdinfo = eventfd_show_fdinfo, 399 #endif 400 .release = eventfd_release, 401 .poll = eventfd_poll, 402 .read = eventfd_read, 403 .write = eventfd_write, 404 .llseek = noop_llseek, 405 }; 406 407 static const struct file_operations eventfd_vpoll_fops = { 408 #ifdef CONFIG_PROC_FS 409 .show_fdinfo = eventfd_show_fdinfo, 410 #endif 411 .release = eventfd_release, 412 .poll = eventfd_vpoll_poll, 413 .read = eventfd_vpoll_read, 414 .write = eventfd_vpoll_write, 415 .llseek = noop_llseek, 416 }; 417 418 /** 419 * eventfd_fget - Acquire a reference of an eventfd file descriptor. 420 * @fd: [in] Eventfd file descriptor. 421 * 422 * Returns a pointer to the eventfd file structure in case of success, or the 423 * following error pointer: 424 * 425 * -EBADF : Invalid @fd file descriptor. 426 * -EINVAL : The @fd file descriptor is not an eventfd file. 427 */ 428 struct file *eventfd_fget(int fd) 429 { 430 struct file *file; 431 432 file = fget(fd); 433 if (!file) 434 return ERR_PTR(-EBADF); 435 if (file->f_op != &eventfd_fops) { 436 fput(file); 437 return ERR_PTR(-EINVAL); 438 } 439 440 return file; 441 } 442 EXPORT_SYMBOL_GPL(eventfd_fget); 443 444 /** 445 * eventfd_ctx_fdget - Acquires a reference to the internal eventfd context. 446 * @fd: [in] Eventfd file descriptor. 447 * 448 * Returns a pointer to the internal eventfd context, otherwise the error 449 * pointers returned by the following functions: 450 * 451 * eventfd_fget 452 */ 453 struct eventfd_ctx *eventfd_ctx_fdget(int fd) 454 { 455 struct eventfd_ctx *ctx; 456 struct fd f = fdget(fd); 457 if (!f.file) 458 return ERR_PTR(-EBADF); 459 ctx = eventfd_ctx_fileget(f.file); 460 fdput(f); 461 return ctx; 462 } 463 EXPORT_SYMBOL_GPL(eventfd_ctx_fdget); 464 465 /** 466 * eventfd_ctx_fileget - Acquires a reference to the internal eventfd context. 467 * @file: [in] Eventfd file pointer. 468 * 469 * Returns a pointer to the internal eventfd context, otherwise the error 470 * pointer: 471 * 472 * -EINVAL : The @fd file descriptor is not an eventfd file. 473 */ 474 struct eventfd_ctx *eventfd_ctx_fileget(struct file *file) 475 { 476 struct eventfd_ctx *ctx; 477 478 if (file->f_op != &eventfd_fops) 479 return ERR_PTR(-EINVAL); 480 481 ctx = file->private_data; 482 kref_get(&ctx->kref); 483 return ctx; 484 } 485 EXPORT_SYMBOL_GPL(eventfd_ctx_fileget); 486 487 static int do_eventfd(unsigned int count, int flags) 488 { 489 struct eventfd_ctx *ctx; 490 const struct file_operations *fops = &eventfd_fops; 491 int fd; 492 493 /* Check the EFD_* constants for consistency. */ 494 BUILD_BUG_ON(EFD_CLOEXEC != O_CLOEXEC); 495 BUILD_BUG_ON(EFD_NONBLOCK != O_NONBLOCK); 496 497 if (flags & ~EFD_FLAGS_SET) 498 return -EINVAL; 499 500 ctx = kmalloc(sizeof(*ctx), GFP_KERNEL); 501 if (!ctx) 502 return -ENOMEM; 503 504 kref_init(&ctx->kref); 505 init_waitqueue_head(&ctx->wqh); 506 ctx->count = count; 507 ctx->flags = flags; 508 ctx->id = ida_simple_get(&eventfd_ida, 0, 0, GFP_KERNEL); 509 510 if (flags & EFD_VPOLL) { 511 fops = &eventfd_vpoll_fops; > 512 ctx->count &= EPOLLALLMASK; 513 } 514 fd = anon_inode_getfd("[eventfd]", fops, ctx, 515 O_RDWR | (flags & EFD_SHARED_FCNTL_FLAGS)); 516 if (fd < 0) 517 eventfd_free_ctx(ctx); 518 519 return fd; 520 } 521 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
