Once we remove the serialising spinlock, a potential race opens up for
non-coherent IOMMUs whereby a caller of .map() can be sure that cache
maintenance has been performed on their new PTE, but will have no
guarantee that such maintenance for table entries above it has actually
completed (e.g. if another CPU took an interrupt immediately after
writing the table entry, but before initiating the DMA sync).

Handling this race safely will add some potentially non-trivial overhead
to installing a table entry, which we would much rather avoid on
coherent systems where it will be unnecessary, and where we are stirivng
to minimise latency by removing the locking in the first place.

To that end, let's introduce an explicit notion of cache-coherency to
io-pgtable, such that we will be able to avoid penalising IOMMUs which
know enough to know when they are coherent.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Whilst the short-descriptor format's split_blk_unmap implementation has
no need to be recursive, it followed the pattern of the LPAE version
anyway for the sake of consistency. With the latter now reworked for
both efficiency and future scalability improvements, tweak the former
similarly, not least to make it less obtuse.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

The current split_blk_unmap implementation suffers from some inscrutable
pointer trickery for creating the tables to replace the block entry, but
more than that it also suffers from hideous inefficiency. For example,
the most pathological case of unmapping a level 3 page from a level 1
block will allocate 513 lower-level tables to remap the entire block at
page granularity, when only 2 are actually needed (the rest can be
covered by level 2 block entries).

Also, we would like to be able to relax the spinlock requirement in
future, for which the roll-back-and-try-again logic for race resolution
would be pretty hideous under the current paradigm.

Both issues can be resolved most neatly by turning things sideways:
instead of repeatedly recursing into __arm_lpae_map() map to build up an
entire new sub-table depth-first, we can directly replace the block
entry with a next-level table of block/page entries, then repeat by
unmapping at the next level if necessary. With a little refactoring of
some helper functions, the code ends up not much bigger than before, but
considerably easier to follow and to adapt in future.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Whilst we don't support the PXN bit at all, so should never encounter a
level 1 section or supersection PTE with it set, it would still be wise
to check both table type bits to resolve any theoretical ambiguity.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

iommu_device_register returns an error code and, although it currently
never fails, we should check its return value anyway.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
[will: adjusted to follow arm-smmu.c]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

of_device_ids are not supposed to change at runtime. All functions
working with of_device_ids provided by <linux/of.h> work with const
of_device_ids. So mark the non-const structs as const.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Revision C of IORT now allows us to identify ARM MMU-401 and the Cavium
ThunderX implementation. Wire them up so that we can probe these models
once firmware starts using the new codes in place of generic ones, and
so that the appropriate features and quirks get enabled when we do.

For the sake of backports and mitigating sychronisation problems with
the ACPICA headers, we'll carry a backup copy of the new definitions
locally for the short term to make life simpler.

CC: stable@vger.kernel.org # 4.10
Acked-by: NRobert Richter <rrichter@cavium.com>
Tested-by: NRobert Richter <rrichter@cavium.com>
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

File size before:
   text	   data	    bss	    dec	    hex	filename
   6146	     56	      9	   6211	   1843	drivers/iommu/io-pgtable-arm-v7s.o

File size After adding 'const':
   text	   data	    bss	    dec	    hex	filename
   6170	     24	      9	   6203	   183b	drivers/iommu/io-pgtable-arm-v7s.o
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Waiting for a CMD_SYNC to be processed involves waiting for the command
queue to drain, which can take an awful lot longer than waiting for a
single entry to become available. Consequently, the common timeout value
of 100us has been observed to be too short on some platforms when a
CMD_SYNC is issued into a queued full of TLBI commands.

This patch resolves the issue by using a different (1s) timeout when
waiting for the CMDQ to drain and using a simple back-off mechanism
when polling the cons pointer in the absence of WFE support.
Signed-off-by: NSunil Goutham <sgoutham@cavium.com>
[will: rewrote commit message and cosmetic changes]
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Add a new Kconfig option to enable/disable the extra warnings
from the vblank evade code. For now we'll keep the warning
about an actually missed vblank always enabled as that can have
an actual user visible impact. But if we miss the deadline
othrwise there's no real need to bother the user with that.
We'll want these warnings enabled during development however
so that we can catch regressions.

Based on the reports it looks like this is still very easy
to hit on SKL, so we have more work ahead of us to optimize
the crtiical section further.

Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reported-by: NJens Axboe <axboe@kernel.dk>
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Fixes: e1edbd44 ("drm/i915: Complain if we take too long under vblank evasion.")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

gcc-7 warns about 'const SIMPLE_DEV_PM_OPS', as that macro already contains
a 'const' keyword:

drivers/input/keyboard/cros_ec_keyb.c:663:14: error: duplicate 'const' declaration specifier [-Werror=duplicate-decl-specifier]
 static const SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);

This removes the extra one.

Fixes: 6af6dc2d ("input: Add ChromeOS EC keyboard driver")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

These were ineffective due to touching the list without the alarm lock,
but should no longer be required.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

The idea here was to avoid having to "manually" program the HW if there's
a new earliest alarm.  This was lazy and bad, as it leads to loads of fun
races between inter-related callers (ie. therm).

Turns out, it's not so difficult after all.  Go figure ;)
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

At least therm/fantog "attempts" to work around this issue, which could
lead to corruption of the pending alarm list.

Fix it properly by not updating the timestamp without the lock held, or
trying to add an already pending alarm to the pending alarm list....
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

If the time to the next alarm is short enough, we could race with HW and
end up with an ~4 second delay until it triggers.

Fix this by checking again after we update HW.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

Fixes a race where we can miss an alarm that triggers while we're already
processing previous alarms.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

object->engine cannot be NULL, it's either valid, or an error pointer.

This particular condition shouldn't actually be possible, but just in
case, we'll keep it.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

This reg has moved on Pascal, and causes a bus fault.

We never use the value anyway, so just remove the read.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

The DRM core used to only call prepare_fb/cleanup_fb() when a plane's
framebuffer changed, which achieved the desired effect.

It's apparently now up to the driver to decide on its own.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org [4.11+]

This "optimisation" (which was originally meant to skip updating cursor
settings in the core channel on position-only updates) turned out to be
pointless in the final design of the code before it was merged.

Remove it completely, as it breaks other cases.
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org [4.10+]

Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

This reverts commit 0e2eb7d1

  Author: Bart Van Assche <bart.vanassche@sandisk.com>
  Date:   Thu Mar 30 10:12:39 2017 -0700

      target: Fix VERIFY and WRITE VERIFY command parsing

This patch broke existing behaviour for WRITE_VERIFY because
it dropped the original SCF_SCSI_DATA_CDB assignment for
bytchk = 0 so target_cmd_size_check() no longer rejected
this case, allowing an overflow case to trigger an OOPs
in iscsi-target.

Since the short term and long term fixes are still being
discussed, revert it for now since it's late in the merge
window and try again in v4.13-rc1.

Conflicts:
	drivers/target/target_core_sbc.c
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

If we had badblocks/poison in the metadata area of a BTT, recreating the
BTT would not clear the poison in all cases, notably the flog area. This
is because rw_bytes will only clear errors if the request being sent
down is 512B aligned and sized.

Make sure that when writing the map and info blocks, the rw_bytes being
sent are of the correct size/alignment. For the flog, instead of doing
the smaller log_entry writes only, first do a 'wipe' of the entire area
by writing zeroes in large enough chunks so that errors get cleared.

Cc: Andy Rudoff <andy.rudoff@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NVishal Verma <vishal.l.verma@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

nsio_rw_bytes can clear media errors, but this cannot be done while we
are in an atomic context due to locking within ACPI. From the BTT,
->rw_bytes may be called either from atomic or process context depending
on whether the calls happen during initialization or during IO.

During init, we want to ensure error clearing happens, and the flag
marking process context allows nsio_rw_bytes to do that. When called
during IO, we're in atomic context, and error clearing can be skipped.

Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NVishal Verma <vishal.l.verma@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

PlayStation 1/2 joypads can be connected directly to the SPI interface.
Signed-off-by: NTomohiro Yoshidomi <sylph23k@gmail.com>
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>

Use the new enums for setting and getting the fan control mode.
Fixes problems due to previous inconsistencies between enums.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Use the new enums for setting and getting the fan control mode.
Fixes problems due to previous inconsistencies between enums.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Use the new enums for setting and getting the fan control mode.
Fixes problems due to previous inconsistencies between enums.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Make the interface consistent.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Add common fan enums that can be used for both
powerplay and dpm.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Add some new SMU messages.
Signed-off-by: NRex Zhu <Rex.Zhu@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

The problem is that executing the jobs in the right order doesn't give you the right result
because consecutive jobs executed on the same engine are pipelined.
In other words job B does it buffer read before job A has written it's result.
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Need to increment after the fence check.
Signed-off-by: NChunming Zhou <David1.Zhou@amd.com>
Reviewed-by: NJunwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Reviewed-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Need to use the atomfirmware interface rather than atombios since
soc15 is atomfirmware based.
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NHarry Wentland <harry.wentland@amd.com>
Acked-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Update the scratch reg for when the engine is hung.
Reviewed-by: NChunming Zhou <david1.zhou@amd.com>
Acked-by: NHarry Wentland <harry.wentland@amd.com>
Acked-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Encountered a dozen of exact same backtraces when mesa's
pb_cache_release_all_buffers is called after that a gpu reset failed.

v2: Remove superfluous error message added in v1.

bug: https://bugs.freedesktop.org/show_bug.cgi?id=96271Signed-off-by: NJulien Isorce <jisorce@oblong.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Free up kmalloc allocated memory if failure happens while handling L2P
table transfer in nvme_nvm_get_l2p_tbl.

Fixes: 8e79b5cb ("lightnvm: move block provisioning to targets")
Signed-off-by: NRakesh Pandit <rakesh@tuxera.com>
Reviewed-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

There is no point to ask how many device-dax instances the kernel should
support. Since we are already using a dynamic major number, just allow
the max number of minors by default and be done. This also fixes the
fact that the proposed max for the NR_DEV_DAX range was larger than what
could be supported by alloc_chrdev_region().

Fixes: ba09c01d ("dax: convert to the cdev api")
Reported-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

PFs and VFs share the same structure of NDOs today,
and the VFs explicitly fails the ndo_xdp() callback stating
it doesn't support XDP.

This results in lots of:

  [qede_xdp:1032(enp131s2)]VFs don't support XDP
  ------------[ cut here ]------------
  WARNING: CPU: 4 PID: 1426 at net/core/rtnetlink.c:1637 rtnl_dump_ifinfo+0x354/0x3c0
  ...
  Call Trace:
    ? __alloc_skb+0x9b/0x1d0
    netlink_dump+0x122/0x290
    netlink_recvmsg+0x27d/0x430
    sock_recvmsg+0x3d/0x50
  ...

As every dump request for the VF interface info would fail due to
rtnl_xdp_fill() returning an error code.

To resolve this, introduce a subset of the NDOs meant for the VF
in a seperate structure and register that one instead for VFs,
and omit the ndo_xdp initialization.

Fixes: 40b8c454 ("qede: Prevent VFs from using XDP")
Signed-off-by: NYuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>