null_blk_zoned creation fails if the number of zones specified is equal to or is
smaller than 64 due to a memory allocation failure in blk_alloc_zones(). With
such a small number of zones, the required memory size for all zones descriptors
fits in a single page, and the page order for alloc_pages_node() is zero. Allow
this value in blk_alloc_zones() for the allocation to succeed.

Fixes: bf505456 "block: Introduce blk_revalidate_disk_zones()"
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Matthew pointed out that the ioctx_table is susceptible to spectre v1,
because the index can be controlled by an attacker.  The below patch
should mitigate the attack for all of the aio system calls.

Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We don't need to zero fill the bio if not using kernel allocated pages.

Fixes: f3587d76 ("block: Clear kernel memory before copying to user") # v4.20-rc2
Reported-by: Todd Aiken <taiken@mvtech.ca>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: stable@vger.kernel.org
Cc: Bart Van Assche <bvanassche@acm.org>
Tested-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph.

* 'nvme-4.20' of git://git.infradead.org/nvme:
  nvmet-rdma: fix response use after free
  nvme: validate controller state before rescheduling keep alive

After the direct dispatch corruption fix, we permanently disallow direct
dispatch of non read/write requests. This works fine off the normal IO
path, as they will be retried like any other failed direct dispatch
request. But for the blk_insert_cloned_request() that only DM uses to
bypass the bottom level scheduler, we always first attempt direct
dispatch. For some types of requests, that's now a permanent failure,
and no amount of retrying will make that succeed. This results in a
livelock.

Instead of making special cases for what we can direct issue, and now
having to deal with DM solving the livelock while still retaining a BUSY
condition feedback loop, always just add a request that has been through
->queue_rq() to the hardware queue dispatch list. These are safe to use
as no merging can take place there. Additionally, if requests do have
prepped data from drivers, we aren't dependent on them not sharing space
in the request structure to safely add them to the IO scheduler lists.

This basically reverts ffe81d45 and is based on a patch from Ming,
but with the list insert case covered as well.

Fixes: ffe81d45 ("blk-mq: fix corruption with direct issue")
Cc: stable@vger.kernel.org
Suggested-by: Ming Lei <ming.lei@redhat.com>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

nvmet_rdma_release_rsp() may free the response before using it at error
flow.

Fixes: 8407879c ("nvmet-rdma: fix possible bogus dereference under heavy load")
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Delete operations are seeing NULL pointer references in call_timer_fn.
Tracking these back, the timer appears to be the keep alive timer.

nvme_keep_alive_work() which is tied to the timer that is cancelled
by nvme_stop_keep_alive(), simply starts the keep alive io but doesn't
wait for it's completion. So nvme_stop_keep_alive() only stops a timer
when it's pending. When a keep alive is in flight, there is no timer
running and the nvme_stop_keep_alive() will have no affect on the keep
alive io. Thus, if the io completes successfully, the keep alive timer
will be rescheduled.   In the failure case, delete is called, the
controller state is changed, the nvme_stop_keep_alive() is called while
the io is outstanding, and the delete path continues on. The keep
alive happens to successfully complete before the delete paths mark it
as aborted as part of the queue termination, so the timer is restarted.
The delete paths then tear down the controller, and later on the timer
code fires and the timer entry is now corrupt.

Fix by validating the controller state before rescheduling the keep
alive. Testing with the fix has confirmed the condition above was hit.
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Since commit '2d29c9f8 ("block, bfq: improve asymmetric scenarios
detection")', if there are process groups with I/O requests waiting for
completion, then BFQ tags the scenario as 'asymmetric'. This detection
is needed for preserving service guarantees (for details, see comments
on the computation * of the variable asymmetric_scenario in the
function bfq_better_to_idle).

Unfortunately, commit '2d29c9f8 ("block, bfq: improve asymmetric
scenarios detection")' contains an error exactly in the updating of
the number of groups with I/O requests waiting for completion: if a
group has more than one descendant process, then the above number of
groups, which is renamed from num_active_groups to a more appropriate
num_groups_with_pending_reqs by this commit, may happen to be wrongly
decremented multiple times, namely every time one of the descendant
processes gets all its pending I/O requests completed.

A correct, complete solution should work as follows. Consider a group
that is inactive, i.e., that has no descendant process with pending
I/O inside BFQ queues. Then suppose that num_groups_with_pending_reqs
is still accounting for this group, because the group still has some
descendant process with some I/O request still in
flight. num_groups_with_pending_reqs should be decremented when the
in-flight request of the last descendant process is finally completed
(assuming that nothing else has changed for the group in the meantime,
in terms of composition of the group and active/inactive state of
child groups and processes). To accomplish this, an additional
pending-request counter must be added to entities, and must be
updated correctly.

To avoid this additional field and operations, this commit resorts to
the following tradeoff between simplicity and accuracy: for an
inactive group that is still counted in num_groups_with_pending_reqs,
this commit decrements num_groups_with_pending_reqs when the first
descendant process of the group remains with no request waiting for
completion.

This simplified scheme provides a fix to the unbalanced decrements
introduced by 2d29c9f8. Since this error was also caused by lack
of comments on this non-trivial issue, this commit also adds related
comments.

Fixes: 2d29c9f8 ("block, bfq: improve asymmetric scenarios detection")
Reported-by: Steven Barrett <steven@liquorix.net>
Tested-by: Steven Barrett <steven@liquorix.net>
Tested-by: Lucjan Lucjanov <lucjan.lucjanov@gmail.com>
Reviewed-by: Federico Motta <federico@willer.it>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If we attempt a direct issue to a SCSI device, and it returns BUSY, then
we queue the request up normally. However, the SCSI layer may have
already setup SG tables etc for this particular command. If we later
merge with this request, then the old tables are no longer valid. Once
we issue the IO, we only read/write the original part of the request,
not the new state of it.

This causes data corruption, and is most often noticed with the file
system complaining about the just read data being invalid:

[  235.934465] EXT4-fs error (device sda1): ext4_iget:4831: inode #7142: comm dpkg-query: bad extra_isize 24937 (inode size 256)

because most of it is garbage...

This doesn't happen from the normal issue path, as we will simply defer
the request to the hardware queue dispatch list if we fail. Once it's on
the dispatch list, we never merge with it.

Fix this from the direct issue path by flagging the request as
REQ_NOMERGE so we don't change the size of it before issue.

See also:
  https://bugzilla.kernel.org/show_bug.cgi?id=201685Tested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: 6ce3dd6e ("blk-mq: issue directly if hw queue isn't busy in case of 'none'")
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

These devices support read zero after trim (RZAT), as they advertise to
the OS. However, the OS doesn't believe the SSDs unless they are
explicitly whitelisted.
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph:

"Various fixlets all over."

* 'nvme-4.20' of git://git.infradead.org/nvme:
  nvme-rdma: fix double freeing of async event data
  nvme: flush namespace scanning work just before removing namespaces
  nvme: warn when finding multi-port subsystems without multipathing enabled
  nvme-pci: fix surprise removal
  nvme-fc: initialize nvme_req(rq)->ctrl after calling __nvme_fc_init_request()
  nvme: Free ctrl device name on init failure

There are actually two kinds of discard merge:

- one is the normal discard merge, just like normal read/write request,
and call it single-range discard

- another is the multi-range discard, queue_max_discard_segments(rq->q) > 1

For the former case, queue_max_discard_segments(rq->q) is 1, and we
should handle this kind of discard merge like the normal read/write
request.

This patch fixes the following kernel panic issue[1], which is caused by
not removing the single-range discard request from elevator queue.

Guangwu has one raid discard test case, in which this issue is a bit
easier to trigger, and I verified that this patch can fix the kernel
panic issue in Guangwu's test case.

[1] kernel panic log from Jens's report

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000148
 PGD 0 P4D 0.
 Oops: 0000 [#1] SMP PTI
 CPU: 37 PID: 763 Comm: kworker/37:1H Not tainted \
4.20.0-rc3-00649-ge64d9a554a91-dirty #14  Hardware name: Wiwynn \
Leopard-Orv2/Leopard-DDR BW, BIOS LBM08   03/03/2017       Workqueue: kblockd \
blk_mq_run_work_fn                                            RIP: \
0010:blk_mq_get_driver_tag+0x81/0x120                                       Code: 24 \
10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 00 00 00 \
0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 20 72 37 \
f6 87 b0 00 00 00 02  RSP: 0018:ffffc90004aabd30 EFLAGS: 00010246                     \
  RAX: 0000000000000003 RBX: ffff888465ea1300 RCX: ffffc90004aabde8
 RDX: 00000000ffffffff RSI: ffffc90004aabde8 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff888465ea1348 R09: 0000000000000000
 R10: 0000000000001000 R11: 00000000ffffffff R12: ffff888465ea1300
 R13: 0000000000000000 R14: ffff888465ea1348 R15: ffff888465d10000
 FS:  0000000000000000(0000) GS:ffff88846f9c0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000148 CR3: 000000000220a003 CR4: 00000000003606e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  blk_mq_dispatch_rq_list+0xec/0x480
  ? elv_rb_del+0x11/0x30
  blk_mq_do_dispatch_sched+0x6e/0xf0
  blk_mq_sched_dispatch_requests+0xfa/0x170
  __blk_mq_run_hw_queue+0x5f/0xe0
  process_one_work+0x154/0x350
  worker_thread+0x46/0x3c0
  kthread+0xf5/0x130
  ? process_one_work+0x350/0x350
  ? kthread_destroy_worker+0x50/0x50
  ret_from_fork+0x1f/0x30
 Modules linked in: sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel \
kvm switchtec irqbypass iTCO_wdt iTCO_vendor_support efivars cdc_ether usbnet mii \
cdc_acm i2c_i801 lpc_ich mfd_core ipmi_si ipmi_devintf ipmi_msghandler acpi_cpufreq \
button sch_fq_codel nfsd nfs_acl lockd grace auth_rpcgss oid_registry sunrpc nvme \
nvme_core fuse sg loop efivarfs autofs4  CR2: 0000000000000148                        \

 ---[ end trace 340a1fb996df1b9b ]---
 RIP: 0010:blk_mq_get_driver_tag+0x81/0x120
 Code: 24 10 48 89 7c 24 20 74 21 83 fa ff 0f 95 c0 48 8b 4c 24 28 65 48 33 0c 25 28 \
00 00 00 0f 85 96 00 00 00 48 83 c4 30 5b 5d c3 <48> 8b 87 48 01 00 00 8b 40 04 39 43 \
20 72 37 f6 87 b0 00 00 00 02

Fixes: 445251d0 ("blk-mq: fix discard merge with scheduler attached")
Reported-by: Jens Axboe <axboe@kernel.dk>
Cc: Guangwu Zhang <guazhang@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Some error paths in configuration of admin queue free data buffer
associated with async request SQE without resetting the data buffer
pointer to NULL, This buffer is also freed up again if the controller
is shutdown or reset.
Signed-off-by: Prabhath Sajeepa <psajeepa@purestorage.com>
Reviewed-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

nvme_stop_ctrl can be called also for reset flow and there is no need to
flush the scan_work as namespaces are not being removed. This can cause
deadlock in rdma, fc and loop drivers since nvme_stop_ctrl barriers
before controller teardown (and specifically I/O cancellation of the
scan_work itself) takes place, but the scan_work will be blocked anyways
so there is no need to flush it.

Instead, move scan_work flush to nvme_remove_namespaces() where it really
needs to flush.
Reported-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed by: James Smart <jsmart2021@gmail.com>
Tested-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Without CONFIG_NVME_MULTIPATH enabled a multi-port subsystem might
show up as invididual devices and cause problems, warn about it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

commit e2592217 ("fs: simplify the
generic_write_sync prototype") reworked callers of generic_write_sync(),
and ended up dropping the error return for the directio path. Prior to
that commit, in dio_complete(), an error would be bubbled up the stack,
but after that commit, errors passed on to dio_complete were eaten up.

This was reported on the list earlier, and a fix was proposed in
https://lore.kernel.org/lkml/20160921141539.GA17898@infradead.org/, but
never followed up with.  We recently hit this bug in our testing where
fencing io errors, which were previously erroring out with EIO, were
being returned as success operations after this commit.

The fix proposed on the list earlier was a little short -- it would have
still called generic_write_sync() in case `ret` already contained an
error. This fix ensures generic_write_sync() is only called when there's
no pending error in the write. Additionally, transferred is replaced
with ret to bring this code in line with other callers.

Fixes: e2592217 ("fs: simplify the generic_write_sync prototype")
Reported-by: Ravi Nankani <rnankani@amazon.com>
Signed-off-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
CC: Torsten Mehlan <tomeh@amazon.de>
CC: Uwe Dannowski <uwed@amazon.de>
CC: Amit Shah <aams@amazon.de>
CC: David Woodhouse <dwmw@amazon.co.uk>
CC: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When a PCIe NVMe device is not present, nvme_dev_remove_admin() calls
blk_cleanup_queue() on the admin queue, which frees the hctx for that
queue.  Moments later, on the same path nvme_kill_queues() calls
blk_mq_unquiesce_queue() on admin queue and tries to access hctx of it,
which leads to following OOPS:

Oops: 0000 [#1] SMP PTI
RIP: 0010:sbitmap_any_bit_set+0xb/0x40
Call Trace:
 blk_mq_run_hw_queue+0xd5/0x150
 blk_mq_run_hw_queues+0x3a/0x50
 nvme_kill_queues+0x26/0x50
 nvme_remove_namespaces+0xb2/0xc0
 nvme_remove+0x60/0x140
 pci_device_remove+0x3b/0xb0

Fixes: cb4bfda6 ("nvme-pci: fix hot removal during error handling")
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

__nvme_fc_init_request() invokes memset() on the nvme_fcp_op_w_sgl structure, which
NULLed-out the nvme_req(req)->ctrl field previously set by nvme_fc_init_request().
This apparently was not referenced until commit faf4a44fff ("nvme: support traffic
based keep-alive") which now results in a crash in nvme_complete_rq():

[ 8386.897130] RIP: 0010:panic+0x220/0x26c
[ 8386.901406] Code: 83 3d 6f ee 72 01 00 74 05 e8 e8 54 02 00 48 c7 c6 40 fd 5b b4 48 c7 c7 d8 8d c6 b3 31e
[ 8386.922359] RSP: 0018:ffff99650019fc40 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
[ 8386.930804] RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000006
[ 8386.938764] RDX: 0000000000000000 RSI: 0000000000000082 RDI: ffff8e325f8168b0
[ 8386.946725] RBP: ffff99650019fcb0 R08: 0000000000000000 R09: 00000000000004f8
[ 8386.954687] R10: 0000000000000000 R11: ffff99650019f9b8 R12: ffffffffb3c55f3c
[ 8386.962648] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
[ 8386.970613]  oops_end+0xd1/0xe0
[ 8386.974116]  no_context+0x1b2/0x3c0
[ 8386.978006]  do_page_fault+0x32/0x140
[ 8386.982090]  page_fault+0x1e/0x30
[ 8386.985786] RIP: 0010:nvme_complete_rq+0x65/0x1d0 [nvme_core]
[ 8386.992195] Code: 41 bc 03 00 00 00 74 16 0f 86 c3 00 00 00 66 3d 83 00 41 bc 06 00 00 00 0f 85 e7 00 000
[ 8387.013147] RSP: 0018:ffff99650019fe18 EFLAGS: 00010246
[ 8387.018973] RAX: 0000000000000000 RBX: ffff8e322ae51280 RCX: 0000000000000001
[ 8387.026935] RDX: 0000000000000400 RSI: 0000000000000001 RDI: ffff8e322ae51280
[ 8387.034897] RBP: ffff8e322ae51280 R08: 0000000000000000 R09: ffffffffb2f0b890
[ 8387.042859] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
[ 8387.050821] R13: 0000000000000100 R14: 0000000000000004 R15: ffff8e2b0446d990
[ 8387.058782]  ? swiotlb_unmap_page+0x40/0x40
[ 8387.063448]  nvme_fc_complete_rq+0x2d/0x70 [nvme_fc]
[ 8387.068986]  blk_done_softirq+0xa1/0xd0
[ 8387.073264]  __do_softirq+0xd6/0x2a9
[ 8387.077251]  run_ksoftirqd+0x26/0x40
[ 8387.081238]  smpboot_thread_fn+0x10e/0x160
[ 8387.085807]  kthread+0xf8/0x130
[ 8387.089309]  ? sort_range+0x20/0x20
[ 8387.093198]  ? kthread_stop+0x110/0x110
[ 8387.097475]  ret_from_fork+0x35/0x40
[ 8387.101462] ---[ end trace 7106b0adf5e422f8 ]---

Fixes: faf4a44fff ("nvme: support traffic based keep-alive")
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Free the kobject name that was allocated for the controller device on
failure rather than its parent.

Fixes: d22524a4 ("nvme: switch controller refcounting to use struct device")
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Pull NVMe fix from Christoph.

* 'nvme-4.20' of git://git.infradead.org/nvme:
  nvme-fc: resolve io failures during connect

If an io error occurs on an io issued while connecting, recovery
of the io falls flat as the state checking ends up nooping the error
handler.

Create an err_work work item that is scheduled upon an io error while
connecting. The work thread terminates all io on all queues and marks
the queues as not connected.  The termination of the io will return
back to the callee, which will then back out of the connection attempt
and will reschedule, if possible, the connection attempt.

The changes:
- in case there are several commands hitting the error handler, a
  state flag is kept so that the error work is only scheduled once,
  on the first error. The subsequent errors can be ignored.
- The calling sequence to stop keep alive and terminate the queues
  and their io is lifted from the reset routine. Made a small
  service routine used by both reset and err_work.
- During debugging, found that the teardown path can reference
  an uninitialized pointer, resulting in a NULL pointer oops.
  The aen_ops weren't initialized yet. Add validation on their
  initialization before calling the teardown routine.
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

c2856ae2 ("blk-mq: quiesce queue before freeing queue") has
already fixed this race, however the implied synchronize_rcu()
in blk_mq_quiesce_queue() can slow down LUN probe a lot, so caused
performance regression.

Then 1311326c ("blk-mq: avoid to synchronize rcu inside blk_cleanup_queue()")
tried to quiesce queue for avoiding unnecessary synchronize_rcu()
only when queue initialization is done, because it is usual to see
lots of inexistent LUNs which need to be probed.

However, turns out it isn't safe to quiesce queue only when queue
initialization is done. Because when one SCSI command is completed,
the user of sending command can be waken up immediately, then the
scsi device may be removed, meantime the run queue in scsi_end_request()
is still in-progress, so kernel panic can be caused.

In Red Hat QE lab, there are several reports about this kind of kernel
panic triggered during kernel booting.

This patch tries to address the issue by grabing one queue usage
counter during freeing one request and the following run queue.

Fixes: 1311326c ("blk-mq: avoid to synchronize rcu inside blk_cleanup_queue()")
Cc: Andrew Jones <drjones@redhat.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: linux-scsi@vger.kernel.org
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
Cc: stable <stable@vger.kernel.org>
Cc: jianchao.wang <jianchao.w.wang@oracle.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

A discard cleanup merged into 4.20-rc2 causes fstests xfs/259 to
fall into an endless loop in the discard code. The test is creating
a device that is exactly 2^32 sectors in size to test mkfs boundary
conditions around the 32 bit sector overflow region.

mkfs issues a discard for the entire device size by default, and
hence this throws a sector count of 2^32 into
blkdev_issue_discard(). It takes the number of sectors to discard as
a sector_t - a 64 bit value.

The commit ba5d7385 ("block: cleanup __blkdev_issue_discard")
takes this sector count and casts it to a 32 bit value before
comapring it against the maximum allowed discard size the device
has. This truncates away the upper 32 bits, and so if the lower 32
bits of the sector count is zero, it starts issuing discards of
length 0. This causes the code to fall into an endless loop, issuing
a zero length discards over and over again on the same sector.

Fixes: ba5d7385 ("block: cleanup __blkdev_issue_discard")
Tested-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>

Killed pointless WARN_ON().
Signed-off-by: Jens Axboe <axboe@kernel.dk>

med_power_with_dipm still causes freezes after updating the firmware to
the latest version (DXT04L5Q).

Set model_rev to NULL and blacklist the device.

Cc: stable@vger.kernel.org
Signed-off-by: Diego Viola <diego.viola@gmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We need to copy the io priority, too; otherwise the clone will run
with a different priority than the original one.

Fixes: 43b62ce3 ("block: move bio io prio to a new field")
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>

Fixed up subject, and ordered stores.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When copying to the latency type, we should be passing LATENCY_TYPE_LEN,
not DOMAIN_LEN (this isn't a problem in practice because we only pass
"total" or "I/O"). Fix it by changing all of the strlcpy() calls to use
sizeof().

Fixes: 6c3b7af1 ("kyber: add tracepoints")
Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

LKP recently reported a hang at bootup in the floppy code:

[  245.678853] INFO: task mount:580 blocked for more than 120 seconds.
[  245.679906]       Tainted: G                T 4.19.0-rc6-00172-ga9f38e1d #1
[  245.680959] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  245.682181] mount           D 6372   580      1 0x00000004
[  245.683023] Call Trace:
[  245.683425]  __schedule+0x2df/0x570
[  245.683975]  schedule+0x2d/0x80
[  245.684476]  schedule_timeout+0x19d/0x330
[  245.685090]  ? wait_for_common+0xa5/0x170
[  245.685735]  wait_for_common+0xac/0x170
[  245.686339]  ? do_sched_yield+0x90/0x90
[  245.686935]  wait_for_completion+0x12/0x20
[  245.687571]  __floppy_read_block_0+0xfb/0x150
[  245.688244]  ? floppy_resume+0x40/0x40
[  245.688844]  floppy_revalidate+0x20f/0x240
[  245.689486]  check_disk_change+0x43/0x60
[  245.690087]  floppy_open+0x1ea/0x360
[  245.690653]  __blkdev_get+0xb4/0x4d0
[  245.691212]  ? blkdev_get+0x1db/0x370
[  245.691777]  blkdev_get+0x1f3/0x370
[  245.692351]  ? path_put+0x15/0x20
[  245.692871]  ? lookup_bdev+0x4b/0x90
[  245.693539]  blkdev_get_by_path+0x3d/0x80
[  245.694165]  mount_bdev+0x2a/0x190
[  245.694695]  squashfs_mount+0x10/0x20
[  245.695271]  ? squashfs_alloc_inode+0x30/0x30
[  245.695960]  mount_fs+0xf/0x90
[  245.696451]  vfs_kern_mount+0x43/0x130
[  245.697036]  do_mount+0x187/0xc40
[  245.697563]  ? memdup_user+0x28/0x50
[  245.698124]  ksys_mount+0x60/0xc0
[  245.698639]  sys_mount+0x19/0x20
[  245.699167]  do_int80_syscall_32+0x61/0x130
[  245.699813]  entry_INT80_32+0xc7/0xc7

showing that we never complete that read request. The reason is that
the completion setup is racy - it initializes the completion event
AFTER submitting the IO, which means that the IO could complete
before/during the init. If it does, we are passing garbage to
complete() and we may sleep forever waiting for the event to
occur.

Fixes: 7b7b68bb ("floppy: bail out in open() if drive is not responding to block0 read")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull block layer fixes from Jens Axboe:

 - Two fixes for an ubd regression, one for missing locking, and one for
   a missing initialization of a field. The latter was an old latent
   bug, but it's now visible and triggers (Me, Anton Ivanov)

 - Set of NVMe fixes via Christoph, but applied manually due to a git
   tree mixup (Christoph, Sagi)

 - Fix for a discard split regression, in three patches (Ming)

 - Update libata git trees (Geert)

 - SPDX identifier for sata_rcar (Kuninori Morimoto)

 - Virtual boundary merge fix (Johannes)

 - Preemptively clear memory we are going to pass to userspace, in case
   the driver does a short read (Keith)

* tag 'for-linus-20181109' of git://git.kernel.dk/linux-block:
  block: make sure writesame bio is aligned with logical block size
  block: cleanup __blkdev_issue_discard()
  block: make sure discard bio is aligned with logical block size
  Revert "nvmet-rdma: use a private workqueue for delete"
  nvme: make sure ns head inherits underlying device limits
  nvmet: don't try to add ns to p2p map unless it actually uses it
  sata_rcar: convert to SPDX identifiers
  ubd: fix missing initialization of io_req
  block: Clear kernel memory before copying to user
  MAINTAINERS: Fix remaining pointers to obsolete libata.git
  ubd: fix missing lock around request issue
  block: respect virtual boundary mask in bvecs

Pull Ceph fixes from Ilya Dryomov:
 "Two CephFS fixes (copy_file_range and quota) and a small feature bit
  cleanup"

* tag 'ceph-for-4.20-rc2' of https://github.com/ceph/ceph-client:
  libceph: assume argonaut on the server side
  ceph: quota: fix null pointer dereference in quota check
  ceph: add destination file data sync before doing any remote copy

Pull MIPS fixes from Paul Burton:
 "A couple of small MIPS fixes for 4.20:

   - Extend an array to avoid overruns on some Octeon hardware, fixing a
     bug introduced in 4.3.

   - Fix a coherent DMA regression for systems without cache-coherent
     DMA introduced in the 4.20 merge window"

* tag 'mips_fixes_4.20_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Fix `dma_alloc_coherent' returning a non-coherent allocation
  MIPS: OCTEON: fix out of bounds array access on CN68XX

Obviously the created writesame bio has to be aligned with logical block
size, and use bio_allowed_max_sectors() to retrieve this number.

Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: b49a0871 ("block: remove split code in blkdev_issue_{discard,write_same}")
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Cleanup __blkdev_issue_discard() a bit:

- remove local variable of 'end_sect'
- remove code block of 'fail'

Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Obviously the created discard bio has to be aligned with logical block size.

This patch introduces the helper of bio_allowed_max_sectors() for
this purpose.

Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: 744889b7 ("block: don't deal with discard limit in blkdev_issue_discard()")
Fixes: a22c4d7e ("block: re-add discard_granularity and alignment checks")
Reported-by: Rui Salvaterra <rsalvaterra@gmail.com>
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This reverts commit 2acf70ad.

The commit never really fixed the intended issue and caused all
kinds of other issues, including a use before initialization.
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Whenever we update ns_head info, we need to make sure it is still
compatible with all underlying backing devices because although nvme
multipath doesn't have any explicit use of these limits, other devices
can still be stacked on top of it which may rely on the underlying limits.
Start with unlimited stacking limits, and every info update iterate over
siblings and adjust queue limits.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Even without CONFIG_P2PDMA this results in a error print:
nvmet: no peer-to-peer memory is available that's supported by rxe0 and /dev/nullb0

Fixes: c6925093 ("nvmet: Optionally use PCI P2P memory")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull s390 fixes from Martin Schwidefsky:

 - A fix for the pgtable_bytes misaccounting on s390. The patch changes
   common code part in regard to page table folding and adds extra
   checks to mm_[inc|dec]_nr_[pmds|puds].

 - Add FORCE for all build targets using if_changed

 - Use non-loadable phdr for the .vmlinux.info section to avoid a
   segment overlap that confuses kexec

 - Cleanup the attribute definition for the diagnostic sampling

 - Increase stack size for CONFIG_KASAN=y builds

 - Export __node_distance to fix a build error

 - Correct return code of a PMU event init function

 - An update for the default configs

* tag 's390-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/perf: Change CPUM_CF return code in event init function
  s390: update defconfigs
  s390/mm: Fix ERROR: "__node_distance" undefined!
  s390/kasan: increase instrumented stack size to 64k
  s390/cpum_sf: Rework attribute definition for diagnostic sampling
  s390/mm: fix mis-accounting of pgtable_bytes
  mm: add mm_pxd_folded checks to pgtable_bytes accounting functions
  mm: introduce mm_[p4d|pud|pmd]_folded
  mm: make the __PAGETABLE_PxD_FOLDED defines non-empty
  s390: avoid vmlinux segments overlap
  s390/vdso: add missing FORCE to build targets
  s390/decompressor: add missing FORCE to build targets

Pull xfs fixes from Darrick Wong:

 - fix incorrect dropping of error code from bmap

 - print buffer offsets instead of useless hashed pointers when dumping
   corrupt metadata

 - fix integer overflow in attribute verifier

* tag 'xfs-4.20-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix overflow in xfs_attr3_leaf_verify
  xfs: print buffer offsets when dumping corrupt buffers
  xfs: Fix error code in 'xfs_ioc_getbmap()'

Merge tag 'led-fixes-for-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fixes from Jacek Anaszewski:
 "All three fixes are related to the newly added pattern trigger:

   - remove mutex_lock() from timer callback, which would trigger
     problems related to sleeping in atomic context, the removal is
     harmless since mutex protection turned out to be redundant in this
     case

   - fix pattern parsing to properly handle intervals with brightness == 0

   - fix typos in the ABI documentation"

* tag 'led-fixes-for-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  Documentation: ABI: led-trigger-pattern: Fix typos
  leds: trigger: Fix sleeping function called from invalid context
  Fix pattern handling optimalization

Pull sound fixes from Takashi Iwai:
 "Two small regression fixes for HD-audio: one about vga_switcheroo and
  runtime PM, and another about Oops on some Thinkpads"

* tag 'sound-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Fix incorrect clearance of thinkpad_acpi hooks
  vga_switcheroo: Fix missing gpu_bound call at audio client registration