Currently if many flush requests are submitted to an md device is quick
succession, they are serialized and can take a long to process them all.
We don't really need to call flush all those times - a single flush call
can satisfy all requests submitted before it started.
So keep track of when the current flush started and when it finished,
allow any pending flush that was requested before the flush started
to complete without waiting any more.

Test results from Xiao:

Test is done on a raid10 device which is created by 4 SSDs. The tool is
dbench.

1. The latest linux stable kernel
  Operation                Count    AvgLat    MaxLat
  --------------------------------------------------
  Deltree                    768    10.509    78.305
  Flush                  2078376     0.013    10.094
  Close                  21787697     0.019    18.821
  LockX                    96580     0.007     3.184
  Mkdir                      384     0.008     0.062
  Rename                 1255883     0.191    23.534
  ReadX                  46495589     0.020    14.230
  WriteX                 14790591     7.123    60.706
  Unlink                 5989118     0.440    54.551
  UnlockX                  96580     0.005     2.736
  FIND_FIRST             10393845     0.042    12.079
  SET_FILE_INFORMATION   2415558     0.129    10.088
  QUERY_FILE_INFORMATION 4711725     0.005     8.462
  QUERY_PATH_INFORMATION 26883327     0.032    21.715
  QUERY_FS_INFORMATION   4929409b     0.010     8.238
  NTCreateX              29660080     0.100    53.268

Throughput 1034.88 MB/sec (sync open)  128 clients  128 procs
max_latency=60.712 ms

2. With patch1 "Revert "MD: fix lock contention for flush bios""
  Operation                Count    AvgLat    MaxLat
  --------------------------------------------------
  Deltree                    256     8.326    36.761
  Flush                   693291     3.974   180.269
  Close                  7266404     0.009    36.929
  LockX                    32160     0.006     0.840
  Mkdir                      128     0.008     0.021
  Rename                  418755     0.063    29.945
  ReadX                  15498708     0.007     7.216
  WriteX                 4932310    22.482   267.928
  Unlink                 1997557     0.109    47.553
  UnlockX                  32160     0.004     1.110
  FIND_FIRST             3465791     0.036     7.320
  SET_FILE_INFORMATION    805825     0.015     1.561
  QUERY_FILE_INFORMATION 1570950     0.005     2.403
  QUERY_PATH_INFORMATION 8965483     0.013    14.277
  QUERY_FS_INFORMATION   1643626     0.009     3.314
  NTCreateX              9892174     0.061    41.278

Throughput 345.009 MB/sec (sync open)  128 clients  128 procs
max_latency=267.939 m

3. With patch1 and patch2
  Operation                Count    AvgLat    MaxLat
  --------------------------------------------------
  Deltree                    768     9.570    54.588
  Flush                  2061354     0.666    15.102
  Close                  21604811     0.012    25.697
  LockX                    95770     0.007     1.424
  Mkdir                      384     0.008     0.053
  Rename                 1245411     0.096    12.263
  ReadX                  46103198     0.011    12.116
  WriteX                 14667988     7.375    60.069
  Unlink                 5938936     0.173    30.905
  UnlockX                  95770     0.005     4.147
  FIND_FIRST             10306407     0.041    11.715
  SET_FILE_INFORMATION   2395987     0.048     7.640
  QUERY_FILE_INFORMATION 4672371     0.005     9.291
  QUERY_PATH_INFORMATION 26656735     0.018    19.719
  QUERY_FS_INFORMATION   4887940     0.010     7.654
  NTCreateX              29410811     0.059    28.551

Throughput 1026.21 MB/sec (sync open)  128 clients  128 procs
max_latency=60.075 ms

Cc: <stable@vger.kernel.org> # v4.19+
Tested-by: NXiao Ni <xni@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This reverts commit 5a409b4f.

This patch has two problems.

1/ it make multiple calls to submit_bio() from inside a make_request_fn.
 The bios thus submitted will be queued on current->bio_list and not
 submitted immediately.  As the bios are allocated from a mempool,
 this can theoretically result in a deadlock - all the pool of requests
 could be in various ->bio_list queues and a subsequent mempool_alloc
 could block waiting for one of them to be released.

2/ It aims to handle a case when there are many concurrent flush requests.
  It handles this by submitting many requests in parallel - all of which
  are identical and so most of which do nothing useful.
  It would be more efficient to just send one lower-level request, but
  allow that to satisfy multiple upper-level requests.

Fixes: 5a409b4f ("MD: fix lock contention for flush bios")
Cc: <stable@vger.kernel.org> # v4.19+
Tested-by: NXiao Ni <xni@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Changing state from check_state_check_result to
check_state_compute_result not only is unsafe but also doesn't
appear to serve a valid purpose.  A raid6 check should only be
pushing out extra writes if doing repair and a mis-match occurs.
The stripe dev management will already try and do repair writes
for failing sectors.

This patch makes the raid6 check_state_check_result handling
work more like raid5's.  If somehow too many failures for a
check, just quit the check operation for the stripe.  When any
checks pass, don't try and use check_state_compute_result for
a purpose it isn't needed for and is unsafe for.  Just mark the
stripe as in sync for passing its parity checks and let the
stripe dev read/write code and the bad blocks list do their
job handling I/O errors.

Repro steps from Xiao:

These are the steps to reproduce this problem:
1. redefined OPT_MEDIUM_ERR_ADDR to 12000 in scsi_debug.c
2. insmod scsi_debug.ko dev_size_mb=11000  max_luns=1 num_tgts=1
3. mdadm --create /dev/md127 --level=6 --raid-devices=5 /dev/sde1 /dev/sde2 /dev/sde3 /dev/sde5 /dev/sde6
sde is the disk created by scsi_debug
4. echo "2" >/sys/module/scsi_debug/parameters/opts
5. raid-check

It panic:
[ 4854.730899] md: data-check of RAID array md127
[ 4854.857455] sd 5:0:0:0: [sdr] tag#80 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.859246] sd 5:0:0:0: [sdr] tag#80 Sense Key : Medium Error [current]
[ 4854.860694] sd 5:0:0:0: [sdr] tag#80 Add. Sense: Unrecovered read error
[ 4854.862207] sd 5:0:0:0: [sdr] tag#80 CDB: Read(10) 28 00 00 00 2d 88 00 04 00 00
[ 4854.864196] print_req_error: critical medium error, dev sdr, sector 11656 flags 0
[ 4854.867409] sd 5:0:0:0: [sdr] tag#100 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.869469] sd 5:0:0:0: [sdr] tag#100 Sense Key : Medium Error [current]
[ 4854.871206] sd 5:0:0:0: [sdr] tag#100 Add. Sense: Unrecovered read error
[ 4854.872858] sd 5:0:0:0: [sdr] tag#100 CDB: Read(10) 28 00 00 00 2e e0 00 00 08 00
[ 4854.874587] print_req_error: critical medium error, dev sdr, sector 12000 flags 4000
[ 4854.876456] sd 5:0:0:0: [sdr] tag#101 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.878552] sd 5:0:0:0: [sdr] tag#101 Sense Key : Medium Error [current]
[ 4854.880278] sd 5:0:0:0: [sdr] tag#101 Add. Sense: Unrecovered read error
[ 4854.881846] sd 5:0:0:0: [sdr] tag#101 CDB: Read(10) 28 00 00 00 2e e8 00 00 08 00
[ 4854.883691] print_req_error: critical medium error, dev sdr, sector 12008 flags 4000
[ 4854.893927] sd 5:0:0:0: [sdr] tag#166 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[ 4854.896002] sd 5:0:0:0: [sdr] tag#166 Sense Key : Medium Error [current]
[ 4854.897561] sd 5:0:0:0: [sdr] tag#166 Add. Sense: Unrecovered read error
[ 4854.899110] sd 5:0:0:0: [sdr] tag#166 CDB: Read(10) 28 00 00 00 2e e0 00 00 10 00
[ 4854.900989] print_req_error: critical medium error, dev sdr, sector 12000 flags 0
[ 4854.902757] md/raid:md127: read error NOT corrected!! (sector 9952 on sdr1).
[ 4854.904375] md/raid:md127: read error NOT corrected!! (sector 9960 on sdr1).
[ 4854.906201] ------------[ cut here ]------------
[ 4854.907341] kernel BUG at drivers/md/raid5.c:4190!

raid5.c:4190 above is this BUG_ON:

    handle_parity_checks6()
        ...
        BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */

Cc: <stable@vger.kernel.org> # v3.16+
OriginalAuthor: David Jeffery <djeffery@redhat.com>
Cc: Xiao Ni <xni@redhat.com>
Tested-by: NDavid Jeffery <djeffery@redhat.com>
Signed-off-by: NDavid Jeffy <djeffery@redhat.com>
Signed-off-by: NNigel Croxon <ncroxon@redhat.com>
Signed-off-by: NSong Liu <songliubraving@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

loop is one block device, for any bio submitted to this device,
the upper layer does guarantee that pages added to loop's bio won't
go away when the bio is in-flight.

So mark loop's bvec as ITER_BVEC_FLAG_NO_REF then get_page/put_page
can be saved for serving loop's IO.

Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

xen_biovec_phys_mergeable() only needs .bv_page of the 2nd bio bvec
for checking if the two bvecs can be merged, so pass page to
xen_biovec_phys_mergeable() directly.

No function change.

Cc: ris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: xen-devel@lists.xenproject.org
Cc: Omar Sandoval <osandov@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The loop driver always declares the rotational flag of its device as
rotational, even when the device of the mapped file is nonrotational,
as is the case with SSDs or on tmpfs. This can confuse filesystem tools
which are SSD-aware; in my case I frequently forget to tell mkfs.btrfs
that my loop device on tmpfs is nonrotational, and that I really don't
need any automatic metadata redundancy.

The attached patch fixes this by introspecting the rotational flag of the
mapped file's underlying block device, if it exists. If the mapped file's
filesystem has no associated block device - as is the case on e.g. tmpfs -
we assume nonrotational storage. If there is a better way to identify such
non-devices I'd love to hear them.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: holger@applied-asynchrony.com
Signed-off-by: NHolger Hoffstätte <holger.hoffstaette@googlemail.com>
Signed-off-by: NGwendal Grignou <gwendal@chromium.org>
Signed-off-by: NBenjamin Gordon <bmgordon@chromium.org>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If userspace doesn't end the input with a newline (which can easily
happen if the write happens from a C program that does write(fd,
iface, strlen(iface))), we may end up including garbage from a
previous, longer value in the device_name. For example

# cat device_name

# printf 'eth12' > device_name
# cat device_name
eth12
# printf 'eth3' > device_name
# cat device_name
eth32

I highly doubt anybody is relying on this behaviour, so switch to
simply copying the bytes (we've already checked that size is <
IFNAMSIZ) and unconditionally zero-terminate it; of course, we also
still have to strip a trailing newline.

This is also preparation for future patches.

Fixes: 06f502f5 ("leds: trigger: Introduce a NETDEV trigger")
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NJacek Anaszewski <jacek.anaszewski@gmail.com>

In case of_match_device cannot find a match, return -EINVAL to avoid
NULL pointer dereference.

Fixes: fa4191a6 ("leds: pca9532: Add device tree support")
Signed-off-by: NKangjie Lu <kjlu@umn.edu>
Signed-off-by: NJacek Anaszewski <jacek.anaszewski@gmail.com>

Makoto report a below KASAN error: zram does out-of-bounds read.  Because
strscpy copies from source up to count bytes unconditionally.  It could
cause out-of-bounds read on next object in slab.

To prevent it, use strlcpy which checks source's length automatically.

   BUG: KASAN: slab-out-of-bounds in strscpy+0x68/0x154
   Read of size 8 at addr ffffffc0c3495a00 by task system_server/1314
   ..
   Call trace:
     strscpy+0x68/0x154
     idle_store+0xc4/0x34c
     dev_attr_store+0x50/0x6c
     sysfs_kf_write+0x98/0xb4
     kernfs_fop_write+0x198/0x260
     __vfs_write+0x10c/0x338
     vfs_write+0x114/0x238
     SyS_write+0xc8/0x168
     __sys_trace_return+0x0/0x4

   Allocated by task 1314:
    __kmalloc+0x280/0x318
    kernfs_fop_write+0xac/0x260
    __vfs_write+0x10c/0x338
    vfs_write+0x114/0x238
    SyS_write+0xc8/0x168
    __sys_trace_return+0x0/0x4

   Freed by task 2855:
    kfree+0x138/0x630
    kernfs_put_open_node+0x10c/0x124
    kernfs_fop_release+0xd8/0x114
    __fput+0x130/0x2a4
    ____fput+0x1c/0x28
    task_work_run+0x16c/0x1c8
    do_notify_resume+0x2bc/0x107c
    work_pending+0x8/0x10

   The buggy address belongs to the object at ffffffc0c3495a00
    which belongs to the cache kmalloc-128 of size 128
   The buggy address is located 0 bytes inside of
    128-byte region [ffffffc0c3495a00, ffffffc0c3495a80)
   The buggy address belongs to the page:
   page:ffffffbf030d2500 count:1 mapcount:0 mapping:          (null) index:0x0 compound_mapcount: 0
   flags: 0x4000000000010200(slab|head)
   page dumped because: kasan: bad access detected

   Memory state around the buggy address:
    ffffffc0c3495900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    ffffffc0c3495980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
   >ffffffc0c3495a00: 04 fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                      ^
    ffffffc0c3495a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
    ffffffc0c3495b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Link: http://lkml.kernel.org/r/20190319231911.145968-1-minchan@kernel.org
Cc: <stable@vger.kernel.org>	[5.0]
Signed-off-by: NMinchan Kim <minchan@kernel.org>
Reported-by: NMakoto Wu <makotowu@google.com>
Reviewed-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

IOMMUs using ARMv7 short-descriptor format require page tables (level 1
and 2) to be allocated within the first 4GB of RAM, even on 64-bit
systems.

For level 1/2 pages, ensure GFP_DMA32 is used if CONFIG_ZONE_DMA32 is
defined (e.g.  on arm64 platforms).

For level 2 pages, allocate a slab cache in SLAB_CACHE_DMA32.  Note that
we do not explicitly pass GFP_DMA[32] to kmem_cache_zalloc, as this is
not strictly necessary, and would cause a warning in mm/sl*b.c, as we
did not update GFP_SLAB_BUG_MASK.

Also, print an error when the physical address does not fit in
32-bit, to make debugging easier in the future.

Link: http://lkml.kernel.org/r/20181210011504.122604-3-drinkcat@chromium.org
Fixes: ad67f5a6 ("arm64: replace ZONE_DMA with ZONE_DMA32")
Signed-off-by: NNicolas Boichat <drinkcat@chromium.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Huaisheng Ye <yehs1@lenovo.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sasha Levin <Alexander.Levin@microsoft.com>
Cc: Tomasz Figa <tfiga@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yong Wu <yong.wu@mediatek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A check for vif is made in vnt_interrupt_work.

There is a small chance of leaving interrupt disabled while vif
is NULL and the work hasn't been scheduled.
Signed-off-by: NMalcolm Priestley <tvboxspy@gmail.com>
CC: stable@vger.kernel.org # v4.2+
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

After commit 419d6efc, kernel cannot be crashed in the namei
path. However, corrupted nameoff can do harm in the process of
readdir for scenerios without dm-verity as well. Fix it now.

Fixes: 3aa8ec71 ("staging: erofs: add directory operations")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: NGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If a device has an exclusion range specified in the IVRS
table, this region needs to be reserved in the iova-domain
of that device. This hasn't happened until now and can cause
data corruption on data transfered with these devices.

Treat exclusion ranges as reserved regions in the iommu-core
to fix the problem.

Fixes: be2a022c ('x86, AMD IOMMU: add functions to parse IOMMU memory mapping requirements for devices')
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Reviewed-by: NGary R Hook <gary.hook@amd.com>

In case we fail to enable p2pmem on the current namespace, disable the
backing store device before exiting.

Cc: Stephen Bates <sbates@raithlin.com>
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

There are two mistakes for building bvec from sg list for file
backed ns:

- use request data length to compute number of io vector, this way
doesn't consider sg->offset, and the result may be smaller than required
io vectors

- bvec->bv_len isn't capped by sg->length

This patch fixes this issue by building bvec from sg directly, given
the whole IO stack is ready for multi-page bvec.
Reported-by: NYi Zhang <yi.zhang@redhat.com>
Fixes: 3a85a5de ("nvme-loop: add a NVMe loopback host driver")
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

When undergoing state transitions I/O might be requeued, hence
we should always call nvme_mpath_set_live() to schedule requeue_work
whenever the nvme device is live, independent on whether the
old state was live or not.
Signed-off-by: NMartin George <marting@netapp.com>
Signed-off-by: NGargi Srinivas <sring@netapp.com>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

nvme_tcp_end_request just takes the status value and the converts
it to little endian as well as shifting for the phase bit.

Fixes: 43ce38a6d823 ("nvme-tcp: support C2HData with SUCCESS flag")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>

Calling read() for a single byte read will return 2 currently. Use
simple_read_from_buffer() which correctly handles all sizes.

Fixes: 2a9e2740 ("gpio: mockup: rework debugfs interface")
Reviewed-by: NMukesh Ojha <mojha@codeaurora.org>
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>

If the call to of_gpiochip_scan_gpios() in of_gpiochip_add() fails, no
error handling is performed.  This lead to the need of callers to call
of_gpiochip_remove() on failure, which causes "BAD of_node_put() on ..."
if the failure happened before the call to of_node_get().

Fix this by adding proper error handling.

Note that calling gpiochip_remove_pin_ranges() multiple times causes no
harm: subsequent calls are a no-op.

Fixes: dfbd379b ("gpio: of: Return error if gpio hog configuration failed")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NMukesh Ojha <mojha@codeaurora.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

"spi-cs-high" is going to be specified in child node of an SPI
controller's representing attached SPI device, so change the code to
look for it there, instead of checking parent node.
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

SPI GPIO device has more than just "cs-gpio" property in its node and
would request those GPIOs as a part of its initialization. To avoid
applying CS-specific quirk to all of them add a check to make sure
that propname is "cs-gpios".
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When CONFIG_VMAP_STACK=y, __pa() returns incorrect physical address for
a stack virtual address. Stack DMA buffers must be avoided.
Signed-off-by: Nraymond pang <raymondpangxd@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

GT VEBOX DISABLE is only 4 bits wide but it was using a 8 bits wide
mask, the remaning reserved bits is set to 0 causing 4 more
nonexistent VEBOX engines being detected as enabled, triggering the
BUG_ON() because of mismatch between vebox_mask and newly added
VEBOX_MASK().

[   64.081621] [drm:intel_device_info_init_mmio [i915]] vdbox enable: 0005, instances: 0005
[   64.081763] [drm:intel_device_info_init_mmio [i915]] vebox enable: 00f1, instances: 0001
[   64.081825] intel_device_info_init_mmio:925 GEM_BUG_ON(vebox_mask != ({ unsigned int first__ = (VECS0); unsigned int count__ = (2); ((&(dev_priv)->__info)->engine_mask & (((~0UL) - (1UL << (first__)) + 1) & (~0UL >> (64 - 1 - (first__ + count__ - 1))))) >> first__; }))
[   64.082047] ------------[ cut here ]------------
[   64.082054] kernel BUG at drivers/gpu/drm/i915/intel_device_info.c:925!

BSpec: 20680
Fixes: 26376a7e ("drm/i915/icl: Check for fused-off VDBOX and VEBOX instances")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NJosé Roberto de Souza <jose.souza@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190326230223.26336-1-jose.souza@intel.com
(cherry picked from commit 547fcf9b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Free the priv structure only after we are done using it.

Fixes: 1690d8bb ("cpufreq: scpi/scmi: Fix freeing of dynamic OPPs")
Signed-off-by: NVincent Stehlé <vincent.stehle@laposte.net>
Cc: 4.20+ <stable@vger.kernel.org> # 4.20+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This is a Qualcomm based device with a QMI function on interface 4.
It is mode switched from 2020:2030 using a standard eject message.

T:  Bus=01 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  6 Spd=480  MxCh= 0
D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=2020 ProdID=2031 Rev= 2.32
S:  Manufacturer=Mobile Connect
S:  Product=Mobile Connect
S:  SerialNumber=0123456789ABCDEF
C:* #Ifs= 6 Cfg#= 1 Atr=80 MxPwr=500mA
I:* If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=01(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 1 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E:  Ad=83(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
E:  Ad=82(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 2 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E:  Ad=85(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
E:  Ad=84(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=03(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=(none)
E:  Ad=87(I) Atr=03(Int.) MxPS=  10 Ivl=32ms
E:  Ad=86(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 4 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E:  Ad=89(I) Atr=03(Int.) MxPS=   8 Ivl=32ms
E:  Ad=88(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=05(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 5 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=(none)
E:  Ad=8a(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=06(O) Atr=02(Bulk) MxPS= 512 Ivl=125us

Cc: stable@vger.kernel.org
Signed-off-by: NBjørn Mork <bjorn@mork.no>
[ johan: use tabs to align comments in adjacent lines ]
Signed-off-by: NJohan Hovold <johan@kernel.org>

Lorenz Messtechnik has a device that is controlled by the cp210x driver,
so add the device id to the driver.  The device id was provided by
Silicon-Labs for the devices from this vendor.
Reported-by: NUli <t9cpu@web.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NJohan Hovold <johan@kernel.org>

No change to functionality. Simply make transport event messages a little
clearer, and rework CRQ format enums such that we have separate enums for
INIT messages and XPORT events.

[mkp: typo]
Signed-off-by: NTyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Status and error codes are returned in big endian from the VIOS. The values
are translated into a human readable format when logged, but the values are
also logged. This patch byte swaps those values so that they are consistent
between BE and LE platforms.
Signed-off-by: NTyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The VIOS uses the SCSI_ERROR class to report PRLI failures. These errors
are indicated with the combination of a IBMVFC_FC_SCSI_ERROR return status
and 0x8000 error code. Add these codes to cmd_status[] with appropriate
human readable error message.
Signed-off-by: NTyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The text of messages logged with ibmvfc_log_error() always contain the term
"failed". In the case of cancelled commands during EH they are reported
back by the VIOS using error codes. This can be confusing to somebody
looking at these log messages as to whether a command was successfully
cancelled. The following real log message for example it is unclear if the
transaction was actaully cancelled.

<6>sd 0:0:1:1: Cancelling outstanding commands.
<3>sd 0:0:1:1: [sde] Command (28) failed: transaction cancelled (2:6) flags: 0 fcp_rsp: 0, resid=0, scsi_status: 0

Remove prefixing of "failed" to all error logged messages. The
ibmvfc_log_error() function translates the returned error/status codes to a
human readable message already.
Signed-off-by: NTyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If an incoming ELS of type RSCN contains more than one element, zfcp
suboptimally causes repeated erp trigger NOP trace records for each
previously failed port. These could be ports that went away.  It loops over
each RSCN element, and for each of those in an inner loop over all
zfcp_ports.

The trigger to recover failed ports should be just the reception of some
RSCN, no matter how many elements it has. So we can loop over failed ports
separately, and only then loop over each RSCN element to handle the
non-failed ports.

The call chain was:

  zfcp_fc_incoming_rscn
    for (i = 1; i < no_entries; i++)
      _zfcp_fc_incoming_rscn
        list_for_each_entry(port, &adapter->port_list, list)
          if (masked port->d_id match) zfcp_fc_test_link
          if (!port->d_id) zfcp_erp_port_reopen "fcrscn1"   <===

In order the reduce the "flooding" of the REC trace area in such cases, we
factor out handling the failed ports to be outside of the entries loop:

  zfcp_fc_incoming_rscn
    if (no_entries > 1)                                     <===
      list_for_each_entry(port, &adapter->port_list, list)  <===
        if (!port->d_id) zfcp_erp_port_reopen "fcrscn1"     <===
    for (i = 1; i < no_entries; i++)
      _zfcp_fc_incoming_rscn
        list_for_each_entry(port, &adapter->port_list, list)
          if (masked port->d_id match) zfcp_fc_test_link

Abbreviated example trace records before this code change:

Tag            : fcrscn1
WWPN           : 0x500507630310d327
ERP want       : 0x02
ERP need       : 0x02

Tag            : fcrscn1
WWPN           : 0x500507630310d327
ERP want       : 0x02
ERP need       : 0x00                 NOP => superfluous trace record

The last trace entry repeats if there are more than 2 RSCN elements.
Signed-off-by: NSteffen Maier <maier@linux.ibm.com>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Reviewed-by: NJens Remus <jremus@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Suppose more than one non-NPIV FCP device is active on the same channel.
Send I/O to storage and have some of the pending I/O run into a SCSI
command timeout, e.g. due to bit errors on the fibre. Now the error
situation stops. However, we saw FCP requests continue to timeout in the
channel. The abort will be successful, but the subsequent TUR fails.
Scsi_eh starts. The LUN reset fails. The target reset fails.  The host
reset only did an FCP device recovery. However, for non-NPIV FCP devices,
this does not close and reopen ports on the SAN-side if other non-NPIV FCP
device(s) share the same open ports.

In order to resolve the continuing FCP request timeouts, we need to
explicitly close and reopen ports on the SAN-side.

This was missing since the beginning of zfcp in v2.6.0 history commit
ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.").

Note: The FSF requests for forced port reopen could run into FSF request
timeouts due to other reasons. This would trigger an internal FCP device
recovery. Pending forced port reopen recoveries would get dismissed. So
some ports might not get fully reopened during this host reset handler.
However, subsequent I/O would trigger the above described escalation and
eventually all ports would be forced reopen to resolve any continuing FCP
request timeouts due to earlier bit errors.
Signed-off-by: NSteffen Maier <maier@linux.ibm.com>
Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #3.0+
Reviewed-by: NJens Remus <jremus@linux.ibm.com>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

An already deleted SCSI device can exist on the Scsi_Host and remain there
because something still holds a reference.  A new SCSI device with the same
H:C:T:L and FCP device, target port WWPN, and FCP LUN can be created.  When
we try to unblock an rport, we still find the deleted SCSI device and
return early because the zfcp_scsi_dev of that SCSI device is not
ZFCP_STATUS_COMMON_UNBLOCKED. Hence we miss to unblock the rport, even if
the new proper SCSI device would be in good state.

Therefore, skip deleted SCSI devices when iterating the sdevs of the shost.
[cf. __scsi_device_lookup{_by_target}() or scsi_device_get()]

The following abbreviated trace sequence can indicate such problem:

Area           : REC
Tag            : ersfs_3
LUN            : 0x4045400300000000
WWPN           : 0x50050763031bd327
LUN status     : 0x40000000     not ZFCP_STATUS_COMMON_UNBLOCKED
Ready count    : n		not incremented yet
Running count  : 0x00000000
ERP want       : 0x01
ERP need       : 0xc1		ZFCP_ERP_ACTION_NONE

Area           : REC
Tag            : ersfs_3
LUN            : 0x4045400300000000
WWPN           : 0x50050763031bd327
LUN status     : 0x41000000
Ready count    : n+1
Running count  : 0x00000000
ERP want       : 0x01
ERP need       : 0x01

...

Area           : REC
Level          : 4		only with increased trace level
Tag            : ertru_l
LUN            : 0x4045400300000000
WWPN           : 0x50050763031bd327
LUN status     : 0x40000000
Request ID     : 0x0000000000000000
ERP status     : 0x01800000
ERP step       : 0x1000
ERP action     : 0x01
ERP count      : 0x00

NOT followed by a trace record with tag "scpaddy"
for WWPN 0x50050763031bd327.
Signed-off-by: NSteffen Maier <maier@linux.ibm.com>
Fixes: 6f2ce1c6 ("scsi: zfcp: fix rport unblock race with LUN recovery")
Cc: <stable@vger.kernel.org> #2.6.32+
Reviewed-by: NJens Remus <jremus@linux.ibm.com>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Commit a83da8a4 ("scsi: sd: Optimal I/O size should be a multiple
of physical block size") split one conditional into several separate
statements in an effort to provide more accurate warning messages when
a device reports a nonsensical value. However, this reorganization
accidentally dropped the precondition of the reported value being
larger than zero. This lead to a warning getting emitted on devices
that do not report an optimal I/O size at all.

Remain silent if a device does not report an optimal I/O size.

Fixes: a83da8a4 ("scsi: sd: Optimal I/O size should be a multiple of physical block size")
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: <stable@vger.kernel.org>
Reported-by: NHussam Al-Tayeb <ht990332@gmx.com>
Tested-by: NHussam Al-Tayeb <ht990332@gmx.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The scsi_end_request() function calls scsi_cmd_to_driver() indirectly and
hence needs the disk->private_data pointer. Avoid that that pointer is
cleared before all affected I/O requests have finished. This patch avoids
that the following crash occurs:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Call trace:
 scsi_mq_uninit_cmd+0x1c/0x30
 scsi_end_request+0x7c/0x1b8
 scsi_io_completion+0x464/0x668
 scsi_finish_command+0xbc/0x160
 scsi_eh_flush_done_q+0x10c/0x170
 sas_scsi_recover_host+0x84c/0xa98 [libsas]
 scsi_error_handler+0x140/0x5b0
 kthread+0x100/0x12c
 ret_from_fork+0x10/0x18

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reported-by: NJason Yan <yanaijie@huawei.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Use dd to test a SCSI device:

  1. echo "blocked" >/sys/block/sda/device/state
  2. dd if=/dev/sda of=/mnt/t.log bs=1M count=10
  3. echo "running" >/sys/block/sda/device/state

dd should finish this work after step 3, but it hangs.

After step2, the call chain is this:

blk_mq_dispatch_rq_list-->scsi_queue_rq-->prep_to_mq

prep_to_mq will return BLK_STS_RESOURCE, and scsi_queue_rq will
transition it to BLK_STS_DEV_RESOURCE which means that driver can
guarantee that IO dispatch will be triggered in future when the
resource is available.  Need to follow the rule if we set the device
state to running.

[mkp: tweaked commit description and code comment as suggested by Bart]
Signed-off-by: Nzhengbin <zhengbin13@huawei.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

VirtualBox 6.0.x has a new feature where the guest kernel driver passes
info about the origin of the request (e.g. userspace or kernelspace) to
the hypervisor.

If we do not pass this information then when running the 6.0.x userspace
guest-additions tools on a 6.0.x host, some requests will get denied
with a VERR_VERSION_MISMATCH error, breaking vboxservice.service and
the mounting of shared folders marked to be auto-mounted.

This commit implements passing the requestor info to the host, fixing this.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Unlike 'client_ops' which is initialized to 'default_client_ops', the
port operations 'ops' may be left to NULL.
Check the 'ops' value before checking the 'ops->x' value.
Signed-off-by: NFabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Echo "" to /sys/module/kgdboc/parameters/kgdboc will fail with "No such
device” error.

This is caused by function "configure_kgdboc" who init err to ENODEV
when the config is empty (legal input) the code go out with ENODEV
returned.

Fixes: 2dd45316 ("kgdboc: Fix restrict error")
Signed-off-by: NWentao Wang <witallwang@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In half-duplex operation, RX should be started after TX completes.

If DMA is used, there is a case when the DMA transfer completes but the
TX FIFO is not emptied, so the RX cannot be restarted just yet.

Use a boolean variable to store this state and rearm TX interrupt mask
to be signaled again that the transfer finished. In interrupt transmit
handler this variable is used to start RX. A warning message is generated
if RX is activated before TX fifo is cleared.

Fixes: b389f173 ("tty/serial: atmel: RS485 half duplex w/DMA: enable
RX after TX is done")
Signed-off-by: NRazvan Stefanescu <razvan.stefanescu@microchip.com>
Acked-by: NRichard Genoud <richard.genoud@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>