Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A collection of fixes from the past few weeks that should go into 4.5.
  This contains:

   - Overflow fix for sysfs discard show function from Alan.

   - A stacking limit init fix for max_dev_sectors, so we don't end up
     artificially capping some use cases.  From Keith.

   - Have blk-mq proper end unstarted requests on a dying queue, instead
     of pushing that to the driver.  From Keith.

   - NVMe:
        - Update to Kconfig description for NVME_SCSI, since it was
          vague and having it on is important for some SUSE distros.
          From Christoph.
        - Set of fixes from Keith, around surprise removal. Also kills
          the no-merge flag, so it supports merging.

   - Set of fixes for lightnvm from Matias, Javier, and Wenwei.

   - Fix null_blk oops when asked for lightnvm, but not available.  From
     Matias.

   - Copy-to-user EINTR fix from Hannes, fixing a case where SG_IO fails
     if interrupted by a signal.

   - Two floppy fixes from Jiri, fixing signal handling and blocking
     open.

   - A use-after-free fix for O_DIRECT, from Mike Krinkin.

   - A block module ref count fix from Roman Pen.

   - An fs IO wait accounting fix for O_DSYNC from Stephane Gasparini.

   - Smaller reallo fix for xen-blkfront from Bob Liu.

   - Removal of an unused struct member in the deadline IO scheduler,
     from Tahsin.

   - Also from Tahsin, properly initialize inode struct members
     associated with cgroup writeback, if enabled.

   - From Tejun, ensure that we keep the superblock pinned during cgroup
     writeback"

* 'for-linus' of git://git.kernel.dk/linux-block: (25 commits)
  blk: fix overflow in queue_discard_max_hw_show
  writeback: initialize inode members that track writeback history
  writeback: keep superblock pinned during cgroup writeback association switches
  bio: return EINTR if copying to user space got interrupted
  NVMe: Rate limit nvme IO warnings
  NVMe: Poll device while still active during remove
  NVMe: Requeue requests on suspended queues
  NVMe: Allow request merges
  NVMe: Fix io incapable return values
  blk-mq: End unstarted requests on dying queue
  block: Initialize max_dev_sectors to 0
  null_blk: oops when initializing without lightnvm
  block: fix module reference leak on put_disk() call for cgroups throttle
  nvme: fix Kconfig description for BLK_DEV_NVME_SCSI
  kernel/fs: fix I/O wait not accounted for RW O_DSYNC
  floppy: refactor open() flags handling
  lightnvm: allow to force mm initialization
  lightnvm: check overflow and correct mlc pairs
  lightnvm: fix request intersection locking in rrpc
  lightnvm: warn if irqs are disabled in lock laddr
  ...

1 files changed, 6 insertions, 3 deletions

diff --git a/block/bio.c b/block/bio.c
index dbabd48b1934..cf7591551b17 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -874,7 +874,7 @@ int submit_bio_wait(int rw, struct bio *bio)
 	bio->bi_private = &ret;
 	bio->bi_end_io = submit_bio_wait_endio;
 	submit_bio(rw, bio);
-	wait_for_completion(&ret.event);
+	wait_for_completion_io(&ret.event);
 
 	return ret.error;
 }
@@ -1090,9 +1090,12 @@ int bio_uncopy_user(struct bio *bio)
 	if (!bio_flagged(bio, BIO_NULL_MAPPED)) {
 		/*
 		 * if we're in a workqueue, the request is orphaned, so
-		 * don't copy into a random user address space, just free.
+		 * don't copy into a random user address space, just free
+		 * and return -EINTR so user space doesn't expect any data.
 		 */
-		if (current->mm && bio_data_dir(bio) == READ)
+		if (!current->mm)
+			ret = -EINTR;
+		else if (bio_data_dir(bio) == READ)
 			ret = bio_copy_to_iter(bio, bmd->iter);
 		if (bmd->is_our_pages)
 			bio_free_pages(bio);