After the bio has been updated to represent the remaining sectors, reset
bi_done so bio_rewind_iter() does not rewind further than it should.

This resolves a bio_integrity_process() failure on reads where the
original request was split.

Fixes: 63573e35 ("bio-integrity: Restore original iterator on verify stage")
Signed-off-by: NGreg Edwards <gedwards@ddn.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

bio_iov_iter_get_pages() currently only adds pages for the next non-zero
segment from the iov_iter to the bio. That's suboptimal for callers,
which typically try to pin as many pages as fit into the bio. This patch
converts the current bio_iov_iter_get_pages() into a static helper, and
introduces a new helper that allocates as many pages as

 1) fit into the bio,
 2) are present in the iov_iter,
 3) and can be pinned by MM.

Error is returned only if zero pages could be pinned. Because of 3), a
zero return value doesn't necessarily mean all pages have been pinned.
Callers that have to pin every page in the iov_iter must still call this
function in a loop (this is currently the case).

This change matters most for __blkdev_direct_IO_simple(), which calls
bio_iov_iter_get_pages() only once. If it obtains less pages than
requested, it returns a "short write" or "short read", and
__generic_file_write_iter() falls back to buffered writes, which may
lead to data corruption.

Fixes: 72ecad22 ("block: support a full bio worth of IO for simplified bdev direct-io")
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin Wilck <mwilck@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fixes: 72ecad22 ("block: support a full bio worth of IO for simplified bdev direct-io")
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin Wilck <mwilck@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If the last page of the bio is not "full", the length of the last
vector slot needs to be corrected. This slot has the index
(bio->bi_vcnt - 1), but only in bio->bi_io_vec. In the "bv" helper
array, which is shifted by the value of bio->bi_vcnt at function
invocation, the correct index is (nr_pages - 1).

v2: improved readability following suggestions from Ming Lei.
v3: followed a formatting suggestion from Christoph Hellwig.

Fixes: 2cefe4db ("block: add bio_iov_iter_get_pages()")
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin Wilck <mwilck@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph:

"Two small fixes each for the FC code and the target."

* 'nvme-4.18' of git://git.infradead.org/nvme:
  nvmet: only check for filebacking on -ENOTBLK
  nvmet: fixup crash on NULL device path
  nvme: if_ready checks to fail io to deleting controller
  nvmet-fc: fix target sgl list on large transfers

We only need to check for a file-backed namespace if
nvmet_bdev_ns_enable() returns -ENOTBLK. For any other error
it's pointless as the open() error will remain the same.

Fixes: d5eff33e ("nvmet: add simple file backed ns support")
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

When writing an empty string into the device_path attribute the kernel
will crash with

nvmet: failed to open block device (null): (-22)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000

This patch sanitizes the error handling for invalid device path settings.

Fixes: a07b4970 ("nvmet: add a generic NVMe target")
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The scsi block layer requires requests claimed by the error handling be
completed by the error handler. A previous commit allowed completions
to proceed for blk-mq, breaking that assumption.

This patch prevents completions that may race with the timeout handler
by marking the state to complete, restoring the previous behavior.

Fixes: 12f5b931 ("blk-mq: Remove generation seqeunce")
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is preparing for drivers that want to directly alter the state of
their requests. No functional change here.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The revised if_ready checks skipped over the case of returning error when
the controller is being deleted.  Instead it was returning BUSY, which
caused the ios to retry, which caused the ns delete to hang waiting for
the ios to drain.

Stack trace of hang looks like:
 kworker/u64:2   D    0    74      2 0x80000000
 Workqueue: nvme-delete-wq nvme_delete_ctrl_work [nvme_core]
 Call Trace:
  ? __schedule+0x26d/0x820
  schedule+0x32/0x80
  blk_mq_freeze_queue_wait+0x36/0x80
  ? remove_wait_queue+0x60/0x60
  blk_cleanup_queue+0x72/0x160
  nvme_ns_remove+0x106/0x140 [nvme_core]
  nvme_remove_namespaces+0x7e/0xa0 [nvme_core]
  nvme_delete_ctrl_work+0x4d/0x80 [nvme_core]
  process_one_work+0x160/0x350
  worker_thread+0x1c3/0x3d0
  kthread+0xf5/0x130
  ? process_one_work+0x350/0x350
  ? kthread_bind+0x10/0x10
  ret_from_fork+0x1f/0x30

Extend nvmf_fail_nonready_command() to supply the controller pointer so
that the controller state can be looked at. Fail any io to a controller
that is deleting.

Fixes: 3bc32bb1 ("nvme-fabrics: refactor queue ready check")
Fixes: 35897b92 ("nvme-fabrics: fix and refine state checks in __nvmf_check_ready")
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NEwan D. Milne <emilne@redhat.com>
Reviewed-by: NEwan D. Milne <emilne@redhat.com>

The existing code to carve up the sg list expected an sg element-per-page
which can be very incorrect with iommu's remapping multiple memory pages
to fewer bus addresses. To hit this error required a large io payload
(greater than 256k) and a system that maps on a per-page basis. It's
possible that large ios could get by fine if the system condensed the
sgl list into the first 64 elements.

This patch corrects the sg list handling by specifically walking the
sg list element by element and attempting to divide the transfer up
on a per-sg element boundary. While doing so, it still tries to keep
sequences under 256k, but will exceed that rule if a single sg element
is larger than 256k.

Fixes: 48fa362b ("nvmet-fc: simplify sg list handling")
Cc: <stable@vger.kernel.org> # 4.14
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

If the server or network is misbehaving and we get an unexpected reply
we can sometimes miss the request not being started and wait on a
request and never get a response, or even double complete the same
request.  Fix this by replacing the send_complete completion with just a
per command lock.  Add a per command cookie as well so that we can know
if we're getting a double completion for a previous event.  Also check
to make sure we dont have REQUEUED set as that means we raced with the
timeout handler and need to just let the retry occur.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We can race with the snd timeout and the per-request timeout and end up
requeuing the same request twice.  We can't use the send_complete
completion to tell if everything is ok because we hold the tx_lock
during send, so the timeout stuff will block waiting to mark the socket
dead, and we could be marked complete and still requeue.  Instead add a
flag to the socket so we know whether we've been requeued yet.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fix a regression introduced in Linux kernel 4.17 where sending a SCSI
command that does not transfer data (such as TEST UNIT READY) via
/dev/bsg/* results in EINVAL.

Fixes: 17cb960f ("bsg: split handling of SCSI CDBs vs transport requeues")
Cc: <stable@vger.kernel.org> # 4.17+
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTony Battersby <tonyb@cybernetics.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This change adds LOOP_SET_BLOCK_SIZE as one of the supported ioctls
in lo_compat_ioctl. It only takes an unsigned long argument, and
in practice a 32-bit value works fine.
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NEvan Green <evgreen@chromium.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We have
  struct drbd_requests { ... struct bio *private_bio;  ... }
to hold a bio clone for local submission.

On local IO completion, we put that bio, and in case we want to use the
result later, we overload that member to hold the ERR_PTR() of the
completion result,

Which, before v4.3, used to be the passed in "int error",
so we could first bio_put(), then assign.

v4.3-rc1~100^2~21 4246a0b6 block: add a bi_error field to struct bio
changed that:
  	bio_put(req->private_bio);
 -	req->private_bio = ERR_PTR(error);
 +	req->private_bio = ERR_PTR(bio->bi_error);

Which introduces an access after free,
because it was non obvious that req->private_bio == bio.

Impact of that was mostly unnoticable, because we only use that value
in a multiple-failure case, and even then map any "unexpected" error
code to EIO, so worst case we could potentially mask a more specific
error with EIO in a multiple failure case.

Unless the pointed to memory region was unmapped, as is the case with
CONFIG_DEBUG_PAGEALLOC, in which case this results in

  BUG: unable to handle kernel paging request

v4.13-rc1~70^2~75 4e4cbee9 block: switch bios to blk_status_t
changes it further to
  	bio_put(req->private_bio);
  	req->private_bio = ERR_PTR(blk_status_to_errno(bio->bi_status));

And blk_status_to_errno() now contains a WARN_ON_ONCE() for unexpected
values, which catches this "sometimes", if the memory has been reused
quickly enough for other things.

Should also go into stable since 4.3, with the trivial change around 4.13.

Cc: stable@vger.kernel.org
Fixes: 4246a0b6 block: add a bi_error field to struct bio
Reported-by: NSarah Newman <srn@prgmr.com>
Signed-off-by: NLars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This was introduced more than a decade ago when sg chaining was
added, but we never really caught anything with it. The scatterlist
entry size can be critical, since drivers allocate it, so remove
the magic member. Recently it's been triggering allocation stalls
and failures in NVMe.
Tested-by: NJordan Glover <Golden_Miller83@protonmail.ch>
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Pull single NVMe fix from Christoph.

* 'nvme-4.18' of git://git.infradead.org/nvme:
  nvme-rdma: fix possible double free of controller async event buffer

Fix the test that verifies whether bio_op(bio) represents a discard
or write zeroes operation. Compile-tested only.

Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Fixes: 7435e901 ("drbd: zero-out partial unaligned discards on local backend")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Some devices have different queue limits depending on the type of IO. A
classic case is SATA NCQ, where some commands can queue, but others
cannot. If we have NCQ commands inflight and encounter a non-queueable
command, the driver returns busy. Currently we attempt to dispatch more
from the scheduler, if we were able to queue some commands. But for the
case where we ended up stopping due to BUSY, we should not attempt to
retrieve more from the scheduler. If we do, we can get into a situation
where we attempt to queue a non-queueable command, get BUSY, then
successfully retrieve more commands from that scheduler and queue those.
This can repeat forever, starving the non-queuable command indefinitely.

Fix this by NOT attempting to pull more commands from the scheduler, if
we get a BUSY return. This should also be more optimal in terms of
letting requests stay in the scheduler for as long as possible, if we
get a BUSY due to the regular out-of-tags condition.
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch avoids that removing a path controlled by the dm-mpath driver
while mkfs is running triggers the following kernel bug:

    kernel BUG at block/blk-core.c:3347!
    invalid opcode: 0000 [#1] PREEMPT SMP KASAN
    CPU: 20 PID: 24369 Comm: mkfs.ext4 Not tainted 4.18.0-rc1-dbg+ #2
    RIP: 0010:blk_end_request_all+0x68/0x70
    Call Trace:
     <IRQ>
     dm_softirq_done+0x326/0x3d0 [dm_mod]
     blk_done_softirq+0x19b/0x1e0
     __do_softirq+0x128/0x60d
     irq_exit+0x100/0x110
     smp_call_function_single_interrupt+0x90/0x330
     call_function_single_interrupt+0xf/0x20
     </IRQ>

Fixes: f9d03f96 ("block: improve handling of the magic discard payload")
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If reconnect/reset failed where the controller async event buffer
was freed, we might end up freeing it again as we call
nvme_rdma_destroy_admin_queue again in the remove path. Given that
the sequence is guaranteed to serialize by .ctrl_stop, we simply
set ctrl->async_event_sqe.data to NULL and don't free it in future
visits.
Reported-by: NMax Gurtovoy <maxg@mellanox.com>
Tested-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

A device may have boundary restrictions where the number of sectors
between boundaries exceeds its max transfer size. In this case, we need
to cap the max size to the smaller of the two limits.
Reported-by: NJitendra Bhivare <jitendra.bhivare@broadcom.com>
Tested-by: NJitendra Bhivare <jitendra.bhivare@broadcom.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Make sure that RQF_TIMED_OUT is cleared when a request is reused
after a block driver timeout handler has returned BLK_EH_DONE.

Fixes: da661267 ("blk-mq: don't time out requests again that are in the timeout handler")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jianchao Wang <jianchao.w.wang@oracle.com>
Cc: Andrew Randrianasulu <randrianasulu@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

syzbot is reporting NULL pointer dereference at wb_workfn() [1] due to
wb->bdi->dev being NULL. And Dmitry confirmed that wb->state was
WB_shutting_down after wb->bdi->dev became NULL. This indicates that
unregister_bdi() failed to call wb_shutdown() on one of wb objects.

The problem is in cgwb_bdi_unregister() which does cgwb_kill() and thus
drops bdi's reference to wb structures before going through the list of
wbs again and calling wb_shutdown() on each of them. This way the loop
iterating through all wbs can easily miss a wb if that wb has already
passed through cgwb_remove_from_bdi_list() called from wb_shutdown()
from cgwb_release_workfn() and as a result fully shutdown bdi although
wb_workfn() for this wb structure is still running. In fact there are
also other ways cgwb_bdi_unregister() can race with
cgwb_release_workfn() leading e.g. to use-after-free issues:

CPU1                            CPU2
                                cgwb_bdi_unregister()
                                  cgwb_kill(*slot);

cgwb_release()
  queue_work(cgwb_release_wq, &wb->release_work);
cgwb_release_workfn()
                                  wb = list_first_entry(&bdi->wb_list, ...)
                                  spin_unlock_irq(&cgwb_lock);
  wb_shutdown(wb);
  ...
  kfree_rcu(wb, rcu);
                                  wb_shutdown(wb); -> oops use-after-free

We solve these issues by synchronizing writeback structure shutdown from
cgwb_bdi_unregister() with cgwb_release_workfn() using a new mutex. That
way we also no longer need synchronization using WB_shutting_down as the
mutex provides it for CONFIG_CGROUP_WRITEBACK case and without
CONFIG_CGROUP_WRITEBACK wb_shutdown() can be called only once from
bdi_unregister().
Reported-by: Nsyzbot <syzbot+4a7438e774b21ddd8eca@syzkaller.appspotmail.com>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Remove dependencies on HAS_DMA where a Kconfig symbol depends on another
symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST".
In most cases this other symbol is an architecture or platform specific
symbol, or PCI.

Generic symbols and drivers without platform dependencies keep their
dependencies on HAS_DMA, to prevent compiling subsystems or drivers that
cannot work anyway.

This simplifies the dependencies, and allows to improve compile-testing.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: NMark Brown <broonie@kernel.org>
Acked-by: NRobin Murphy <robin.murphy@arm.com>
Reviewed-by: NMatias Bjørling <mb@lightnvm.io>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph:

"Various relatively small fixes, mostly to fix error handling of various
 sorts."

* 'nvme-4.18' of git://git.infradead.org/nvme:
  nvme-pci: limit max IO size and segments to avoid high order allocations
  nvme-pci: move nvme_kill_queues to nvme_remove_dead_ctrl
  nvme-fc: release io queues to allow fast fail
  nvmet: reset keep alive timer in controller enable
  nvme-rdma: don't override opts->queue_size
  nvme-rdma: Fix command completion race at error recovery
  nvme-rdma: fix possible free of a non-allocated async event buffer
  nvme-rdma: fix possible double free condition when failing to create a controller

nvme requires an sg table allocation for each request. If the request
is large, then the allocation can become quite large. For instance,
with our default software settings of 1280KB IO size, we'll need
10248 bytes of sg table. That turns into a 2nd order allocation,
which we can't always guarantee. If we fail the allocation, blk-mq
will retry it later. But there's no guarantee that we'll EVER be
able to allocate that much contigious memory.

Limit the IO size such that we never need more than a single page
of memory. That's a lot faster and more reliable. Then back that
allocation with a mempool, so that we know we'll always be able
to succeed the allocation at some point.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
Acked-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

There is race between nvme_remove and nvme_reset_work that can
lead to io hang.

nvme_remove                    nvme_reset_work
                               -> nvme_remove_dead_ctrl
                                 -> nvme_dev_disable
                                   -> quiesce request_queue
                                 -> queue remove_work
-> cancel_work_sync reset_work
-> nvme_remove_namespaces
  -> splice ctrl->namespaces
                               nvme_remove_dead_ctrl_work
                               -> nvme_kill_queues
  -> nvme_ns_remove               do nothing
    -> blk_cleanup_queue
      -> blk_freeze_queue

Finally, the request_queue is quiesced state when wait freeze,
we will get io hang here. To fix it, move the nvme_kill_queues
from nvme_remove_dead_ctrl_work to nvme_remove_dead_ctrl.
Suggested-by: NKeith Busch <keith.busch@linux.intel.com>
Signed-off-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Rather than leaving io queues quiesced after tearing down an association,
restart them. This allows ios to be replayed, with fastfail ios terminating
and non-fastfail getting into loops of retry.

This follows rdma's lead.
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Reviewed-by: NSagi Grimberg <sagi@grimber.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

If NBD_DISCONNECT_ON_CLOSE is set on a device, then the driver will
issue a disconnect from nbd_release if the device has no remaining
bdev->bd_openers.

Fix ret val so reconfigure with only setting the flag succeeds.
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NDoron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

resp->num is the number of tokens in resp->tok[].  It gets set in
response_parse().  So if n == resp->num then we're reading beyond the
end of the data.

Fixes: 455a7b23 ("block: Add Sed-opal library")
Reviewed-by: NScott Bauer <scott.bauer@intel.com>
Tested-by: NScott Bauer <scott.bauer@intel.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If rq_state == ARRAY_SIZE() then we read one element beyond the end of
the blk_mq_rq_state_name_array[] array.

Fixes: ec6dcf63 ("blk-mq-debugfs: Show more request state information")
Reviewed-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Controllers that are not yet enabled should not really enforce keep alive
timeouts, but we still want to track a timeout and cleanup in case a host
died before it enabled the controller.  Hence, simply reset the keep
alive timer when the controller is enabled.
Suggested-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

That is user argument, and theoretically controller limits can change
over time (over reconnects/resets).  Instead, use the sqsize controller
attribute to check queue depth boundaries and use it to the tagset
allocation.
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

The race is between completing the request at error recovery work and
rdma completions.  If we cancel the request before getting the good
rdma completion we get a NULL deref of the request MR at
nvme_rdma_process_nvme_rsp().

When Canceling the request we return its mr to the mr pool (set mr to
NULL) and also unmap its data.  Canceling the requests while the rdma
queues are active is not safe.  Because rdma queues are active and we
get good rdma completions that can use the mr pointer which may be NULL.
Completing the request too soon may lead also to performing DMA to/from
user buffers which might have been already unmapped.

The commit fixes the race by draining the QP before starting the abort
commands mechanism.
Signed-off-by: NIsrael Rukshin <israelr@mellanox.com>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

If nvme_rdma_configure_admin_queue fails before we allocated
the async event buffer, we will falsly free it because
nvme_rdma_free_queue is freeing it. Fix it by allocating the buffer right
after nvme_rdma_alloc_queue and free it right before nvme_rdma_queue_free
to maintain orderly reverse cleanup sequence.
Reported-by: NIsrael Rukshin <israelr@mellanox.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Failures after nvme_init_ctrl will defer resource cleanups to .free_ctrl
when the reference is released, hence we should not free the controller
queues for these failures.

Fix that by moving controller queues allocation before controller
initialization and correctly freeing them for failures before
initialization and skip them for failures after initialization.
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Commit 0ba99ca4 ("block: Add warning for bi_next not NULL in
bio_endio()") breaks the dm driver. end_clone_bio() detects whether
or not a bio is the last bio associated with a request by checking
the .bi_next field. Commit 0ba99ca4 clears that field before
end_clone_bio() has had a chance to inspect that field. Hence revert
commit 0ba99ca4.

This patch avoids that KASAN reports the following complaint when
running the srp-test software (srp-test/run_tests -c -d -r 10 -t 02-mq):

==================================================================
BUG: KASAN: use-after-free in bio_advance+0x11b/0x1d0
Read of size 4 at addr ffff8801300e06d0 by task ksoftirqd/0/9

CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.18.0-rc1-dbg+ #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
 dump_stack+0xa4/0xf5
 print_address_description+0x6f/0x270
 kasan_report+0x241/0x360
 __asan_load4+0x78/0x80
 bio_advance+0x11b/0x1d0
 blk_update_request+0xa7/0x5b0
 scsi_end_request+0x56/0x320 [scsi_mod]
 scsi_io_completion+0x7d6/0xb20 [scsi_mod]
 scsi_finish_command+0x1c0/0x280 [scsi_mod]
 scsi_softirq_done+0x19a/0x230 [scsi_mod]
 blk_mq_complete_request+0x160/0x240
 scsi_mq_done+0x50/0x1a0 [scsi_mod]
 srp_recv_done+0x515/0x1330 [ib_srp]
 __ib_process_cq+0xa0/0xf0 [ib_core]
 ib_poll_handler+0x38/0xa0 [ib_core]
 irq_poll_softirq+0xe8/0x1f0
 __do_softirq+0x128/0x60d
 run_ksoftirqd+0x3f/0x60
 smpboot_thread_fn+0x352/0x460
 kthread+0x1c1/0x1e0
 ret_from_fork+0x24/0x30

Allocated by task 1918:
 save_stack+0x43/0xd0
 kasan_kmalloc+0xad/0xe0
 kasan_slab_alloc+0x11/0x20
 kmem_cache_alloc+0xfe/0x350
 mempool_alloc_slab+0x15/0x20
 mempool_alloc+0xfb/0x270
 bio_alloc_bioset+0x244/0x350
 submit_bh_wbc+0x9c/0x2f0
 __block_write_full_page+0x299/0x5a0
 block_write_full_page+0x16b/0x180
 blkdev_writepage+0x18/0x20
 __writepage+0x42/0x80
 write_cache_pages+0x376/0x8a0
 generic_writepages+0xbe/0x110
 blkdev_writepages+0xe/0x10
 do_writepages+0x9b/0x180
 __filemap_fdatawrite_range+0x178/0x1c0
 file_write_and_wait_range+0x59/0xc0
 blkdev_fsync+0x46/0x80
 vfs_fsync_range+0x66/0x100
 do_fsync+0x3d/0x70
 __x64_sys_fsync+0x21/0x30
 do_syscall_64+0x77/0x230
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9:
 save_stack+0x43/0xd0
 __kasan_slab_free+0x137/0x190
 kasan_slab_free+0xe/0x10
 kmem_cache_free+0xd3/0x380
 mempool_free_slab+0x17/0x20
 mempool_free+0x63/0x160
 bio_free+0x81/0xa0
 bio_put+0x59/0x60
 end_bio_bh_io_sync+0x5d/0x70
 bio_endio+0x1a7/0x360
 blk_update_request+0xd0/0x5b0
 end_clone_bio+0xa3/0xd0 [dm_mod]
 bio_endio+0x1a7/0x360
 blk_update_request+0xd0/0x5b0
 scsi_end_request+0x56/0x320 [scsi_mod]
 scsi_io_completion+0x7d6/0xb20 [scsi_mod]
 scsi_finish_command+0x1c0/0x280 [scsi_mod]
 scsi_softirq_done+0x19a/0x230 [scsi_mod]
 blk_mq_complete_request+0x160/0x240
 scsi_mq_done+0x50/0x1a0 [scsi_mod]
 srp_recv_done+0x515/0x1330 [ib_srp]
 __ib_process_cq+0xa0/0xf0 [ib_core]
 ib_poll_handler+0x38/0xa0 [ib_core]
 irq_poll_softirq+0xe8/0x1f0
 __do_softirq+0x128/0x60d

The buggy address belongs to the object at ffff8801300e0640
 which belongs to the cache bio-0 of size 200
The buggy address is located 144 bytes inside of
 200-byte region [ffff8801300e0640, ffff8801300e0708)
The buggy address belongs to the page:
page:ffffea0004c03800 count:1 mapcount:0 mapping:ffff88015a563a00 index:0x0 compound_mapcount: 0
flags: 0x8000000000008100(slab|head)
raw: 8000000000008100 dead000000000100 dead000000000200 ffff88015a563a00
raw: 0000000000000000 0000000000330033 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801300e0580: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
 ffff8801300e0600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
>ffff8801300e0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff8801300e0700: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801300e0780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

Cc: Kent Overstreet <kent.overstreet@gmail.com>
Fixes: 0ba99ca4 ("block: Add warning for bi_next not NULL in bio_endio()")
Acked-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

blk_mq_complete_request can only be called for blk-mq drivers, but when
removing the BLK_EH_HANDLED return value, two legacy request timeout
methods incorrectly got switched to call blk_mq_complete_request.
Call __blk_complete_request instead to reinstance the previous behavior.
For that __blk_complete_request needs to be exported.

Fixes: 1fc2b62e ("scsi_transport_fc: complete requests from ->timeout")
Fixes: 0df0bb08 ("null_blk: complete requests from ->timeout")
Reported-by: NJianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>