Re: [PATCH] scsi: avoid a double-fetch and a redundant copy

From: kbuild test robot
Date: Tue Dec 25 2018 - 16:29:19 EST

Next message: Kangjie Lu: "[PATCH] scsi: fix a double-fetch bug in adpt_i2o_passthru"
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Hi Kangjie,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on scsi/for-next]
[also build test ERROR on v4.20 next-20181224]
[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/Kangjie-Lu/scsi-avoid-a-double-fetch-and-a-redundant-copy/20181226-042018
base: https://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git for-next
config: i386-randconfig-x079-201851 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386

All error/warnings (new ones prefixed by >>):

In file included from include/linux/uaccess.h:14:0,
from include/linux/poll.h:12,
from drivers//scsi/sg.c:42:
drivers//scsi/sg.c: In function 'sg_read':
>> drivers//scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:138:41: note: in definition of macro '__inttype'
__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
^
>> drivers//scsi/sg.c:449:14: note: in expansion of macro 'get_user'
retval = get_user(req_pack_id,
^~~~~~~~
>> arch/x86/include/asm/uaccess.h:138:12: error: first argument to '__builtin_choose_expr' not a constant
__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
^
>> arch/x86/include/asm/uaccess.h:174:11: note: in expansion of macro '__inttype'
register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \
^~~~~~~~~
>> drivers//scsi/sg.c:449:14: note: in expansion of macro 'get_user'
retval = get_user(req_pack_id,
^~~~~~~~
>> drivers//scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:180:15: note: in definition of macro 'get_user'
: "0" (ptr), "i" (sizeof(*(ptr)))); \
^~~
>> drivers//scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:180:35: note: in definition of macro 'get_user'
: "0" (ptr), "i" (sizeof(*(ptr)))); \
^~~
>> drivers//scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:181:30: note: in definition of macro 'get_user'
(x) = (__force __typeof__(*(ptr))) __val_gu; \
^~~
--
In file included from include/linux/uaccess.h:14:0,
from include/linux/poll.h:12,
from drivers/scsi/sg.c:42:
drivers/scsi/sg.c: In function 'sg_read':
drivers/scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:138:41: note: in definition of macro '__inttype'
__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
^
drivers/scsi/sg.c:449:14: note: in expansion of macro 'get_user'
retval = get_user(req_pack_id,
^~~~~~~~
>> arch/x86/include/asm/uaccess.h:138:12: error: first argument to '__builtin_choose_expr' not a constant
__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
^
>> arch/x86/include/asm/uaccess.h:174:11: note: in expansion of macro '__inttype'
register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX); \
^~~~~~~~~
drivers/scsi/sg.c:449:14: note: in expansion of macro 'get_user'
retval = get_user(req_pack_id,
^~~~~~~~
drivers/scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:180:15: note: in definition of macro 'get_user'
: "0" (ptr), "i" (sizeof(*(ptr)))); \
^~~
drivers/scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:180:35: note: in definition of macro 'get_user'
: "0" (ptr), "i" (sizeof(*(ptr)))); \
^~~
drivers/scsi/sg.c:450:27: error: request for member 'pack_id' in something not a structure or union
&((sg_io_hdr_t *)buf->pack_id));
^
arch/x86/include/asm/uaccess.h:181:30: note: in definition of macro 'get_user'
(x) = (__force __typeof__(*(ptr))) __val_gu; \
^~~

vim +/pack_id +450 drivers//scsi/sg.c

412
413 static ssize_t
414 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
415 {
416 Sg_device *sdp;
417 Sg_fd *sfp;
418 Sg_request *srp;
419 int req_pack_id = -1;
420 sg_io_hdr_t *hp;
421 struct sg_header *old_hdr = NULL;
422 int retval = 0;
423
424 /*
425 * This could cause a response to be stranded. Close the associated
426 * file descriptor to free up any resources being held.
427 */
428 retval = sg_check_file_access(filp, __func__);
429 if (retval)
430 return retval;
431
432 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
433 return -ENXIO;
434 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
435 "sg_read: count=%d\n", (int) count));
436
437 if (!access_ok(VERIFY_WRITE, buf, count))
438 return -EFAULT;
439 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
440 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
441 if (!old_hdr)
442 return -ENOMEM;
443 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
444 retval = -EFAULT;
445 goto free_old_hdr;
446 }
447 if (old_hdr->reply_len < 0) {
448 if (count >= SZ_SG_IO_HDR) {
> 449 retval = get_user(req_pack_id,
> 450 &((sg_io_hdr_t *)buf->pack_id));
451 if (retval) {
452 retval = -EFAULT;
453 goto free_old_hdr;
454 }
455 }
456 } else
457 req_pack_id = old_hdr->pack_id;
458 }
459 srp = sg_get_rq_mark(sfp, req_pack_id);
460 if (!srp) { /* now wait on packet to arrive */
461 if (atomic_read(&sdp->detaching)) {
462 retval = -ENODEV;
463 goto free_old_hdr;
464 }
465 if (filp->f_flags & O_NONBLOCK) {
466 retval = -EAGAIN;
467 goto free_old_hdr;
468 }
469 retval = wait_event_interruptible(sfp->read_wait,
470 (atomic_read(&sdp->detaching) ||
471 (srp = sg_get_rq_mark(sfp, req_pack_id))));
472 if (atomic_read(&sdp->detaching)) {
473 retval = -ENODEV;
474 goto free_old_hdr;
475 }
476 if (retval) {
477 /* -ERESTARTSYS as signal hit process */
478 goto free_old_hdr;
479 }
480 }
481 if (srp->header.interface_id != '\0') {
482 retval = sg_new_read(sfp, buf, count, srp);
483 goto free_old_hdr;
484 }
485
486 hp = &srp->header;
487 if (old_hdr == NULL) {
488 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
489 if (! old_hdr) {
490 retval = -ENOMEM;
491 goto free_old_hdr;
492 }
493 }
494 memset(old_hdr, 0, SZ_SG_HEADER);
495 old_hdr->reply_len = (int) hp->timeout;
496 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
497 old_hdr->pack_id = hp->pack_id;
498 old_hdr->twelve_byte =
499 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
500 old_hdr->target_status = hp->masked_status;
501 old_hdr->host_status = hp->host_status;
502 old_hdr->driver_status = hp->driver_status;
503 if ((CHECK_CONDITION & hp->masked_status) ||
504 (DRIVER_SENSE & hp->driver_status))
505 memcpy(old_hdr->sense_buffer, srp->sense_b,
506 sizeof (old_hdr->sense_buffer));
507 switch (hp->host_status) {
508 /* This setup of 'result' is for backward compatibility and is best
509 ignored by the user who should use target, host + driver status */
510 case DID_OK:
511 case DID_PASSTHROUGH:
512 case DID_SOFT_ERROR:
513 old_hdr->result = 0;
514 break;
515 case DID_NO_CONNECT:
516 case DID_BUS_BUSY:
517 case DID_TIME_OUT:
518 old_hdr->result = EBUSY;
519 break;
520 case DID_BAD_TARGET:
521 case DID_ABORT:
522 case DID_PARITY:
523 case DID_RESET:
524 case DID_BAD_INTR:
525 old_hdr->result = EIO;
526 break;
527 case DID_ERROR:
528 old_hdr->result = (srp->sense_b[0] == 0 &&
529 hp->masked_status == GOOD) ? 0 : EIO;
530 break;
531 default:
532 old_hdr->result = EIO;
533 break;
534 }
535
536 /* Now copy the result back to the user buffer. */
537 if (count >= SZ_SG_HEADER) {
538 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
539 retval = -EFAULT;
540 goto free_old_hdr;
541 }
542 buf += SZ_SG_HEADER;
543 if (count > old_hdr->reply_len)
544 count = old_hdr->reply_len;
545 if (count > SZ_SG_HEADER) {
546 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
547 retval = -EFAULT;
548 goto free_old_hdr;
549 }
550 }
551 } else
552 count = (old_hdr->result == 0) ? 0 : -EIO;
553 sg_finish_rem_req(srp);
554 sg_remove_request(sfp, srp);
555 retval = count;
556 free_old_hdr:
557 kfree(old_hdr);
558 return retval;
559 }
560

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Next message: Kangjie Lu: "[PATCH] scsi: fix a double-fetch bug in adpt_i2o_passthru"
Previous message: Linus Torvalds: "Re: [GIT PULL for v4.21] second set of media patches: ipu3 driver"
In reply to: Kangjie Lu: "[PATCH] scsi: avoid a double-fetch and a redundant copy"
Next in thread: kbuild test robot: "Re: [PATCH] scsi: avoid a double-fetch and a redundant copy"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]