Track the temporary wakerefs used within the selftests so that leaks are
clear.

v2: Add a couple of coarse annotations for mock selftests as we now
loudly warn about the errors.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-14-chris@chris-wilson.co.uk

Keep track of the temporary rpm wakeref used for panel backlight access,
so that we can cancel it immediately upon release and so more clearly
identify leaks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-13-chris@chris-wilson.co.uk

Keep track of the temporary rpm wakeref inside hotplug detection, so
that we can cancel it immediately upon release and so clearly identify
leaks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-12-chris@chris-wilson.co.uk

Keep track of the rpm wakeref used for framebuffer access so that we can
cancel upon release and so more clearly identify leaks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-11-chris@chris-wilson.co.uk

Keep track of the temporary rpm wakerefs used for user access to the
device, so that we can cancel them upon release and clearly identify any
leaks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-10-chris@chris-wilson.co.uk

Keep track of our acquired wakeref for interacting with the guc, so that
we can cancel it upon release and so clearly identify leaks.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-9-chris@chris-wilson.co.uk

Track the wakeref used for temporary access to the device, and discard
it upon release so that leaks can be identified.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-8-chris@chris-wilson.co.uk

Keep track of our wakeref used to keep the device awake so we can catch
any leak.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-7-chris@chris-wilson.co.uk

As debugfs has a simple pattern of taking a rpm wakeref around the user
access, we can track the local reference and drop it as soon as
possible.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-6-chris@chris-wilson.co.uk

As sysfs has a simple pattern of taking a rpm wakeref around the user
access, we can track the local reference and drop it as soon as
possible.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-5-chris@chris-wilson.co.uk

Keep hold of the local wakeref used in error handling, to cancel
the tracking upon release so that leaks can be identified.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-4-chris@chris-wilson.co.uk

Record the wakeref used for keeping the device awake as the GPU is
executing requests and be sure to cancel the tracking upon parking.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-3-chris@chris-wilson.co.uk

The majority of runtime-pm operations are bounded and scoped within a
function; these are easy to verify that the wakeref are handled
correctly. We can employ the compiler to help us, and reduce the number
of wakerefs tracked when debugging, by passing around cookies provided
by the various rpm_get functions to their rpm_put counterpart. This
makes the pairing explicit, and given the required wakeref cookie the
compiler can verify that we pass an initialised value to the rpm_put
(quite handy for double checking error paths).

For regular builds, the compiler should be able to eliminate the unused
local variables and the program growth should be minimal. Fwiw, it came
out as a net improvement as gcc was able to refactor rpm_get and
rpm_get_if_in_use together,

v2: Just s/rpm_put/rpm_put_unchecked/ everywhere, leaving the manual
mark up for smaller more targeted patches.
v3: Mention the cookie in Returns
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-2-chris@chris-wilson.co.uk

Everytime we take a wakeref, record the stack trace of where it was
taken; clearing the set if we ever drop back to no owners. For debugging
a rpm leak, we can look at all the current wakerefs and check if they
have a matching rpm_put.

v2: Use skip=0 for unwinding the stack as it appears our noinline
function doesn't appear on the stack (nor does save_stack_trace itself!)
v3: Allow rpm->debug_count to disappear between inspections and so
avoid calling krealloc(0) as that may return a ZERO_PTR not NULL! (Mika)
v4: Show who last acquire/released the runtime pm
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Tested-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190114142129.24398-1-chris@chris-wilson.co.uk

Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>

The wait-for-idle used from within the shrinker_lock_uninterruptible
depends on the struct_mutex locking state being known and declared to
i915_request_wait(). As it is conceivable that we reach the vmap
notifier from underneath struct_mutex (and so keep on relying on the
mutex_trylock_recursive), we should not blindly call i915_request_wait.

In the process we can remove the dubious polling to acquire
struct_mutex, and simply act, or not, on a successful trylock.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190109164204.23935-2-chris@chris-wilson.co.uk

If the current process is being killed (it was interrupted with SIGKILL
or equivalent), it will not make any progress in page allocation and we
can abort performing the shrinking on its behalf. So we can use
mutex_lock_killable() instead (although this path should only be
reachable from kswapd currently).

Tvrtko pointed out that it should also be reachable from debugfs, which
he would prefer retain its interruptiblity. As a compromise, killable is a
step in the right direction!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190109164204.23935-1-chris@chris-wilson.co.uk

If we find an incompletely setup vma inside the request/engine at the
time of a hang, it may not have vma->pages initialised, so skip
capturing the object before we iterate over NULL.

Spotted by Matthew in preparation for using unpinned vma to track engine
state.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190110111522.11023-1-chris@chris-wilson.co.uk

The only gen8+ platform that has the feature is BDW, but we don't define
the feature flag on any BDW platform and we only have partial support in
the gen8 path (irq enabling code, but no handler).
The only thing we could do in the irq handler is report the error
to userspace, but no one asked/cared about that since BDW was
released so it is relatively safe to assume that even if we added the
message no one would look at it. Just drop the dead code from the
driver instead.
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190109213147.16851-1-daniele.ceraolospurio@intel.com

commit 4a15c75c ("drm/i915: Introduce per-engine workarounds")
refactored the workaround code to have functions per-engine, but didn't
call any of them from logical_xcs_ring_init. Since we do have a non-RCS
workaround for KBL (WaKBLVECSSemaphoreWaitPoll) we do need to call
intel_engine_init_workarounds for non-RCS engines.
Note that whitelist is still RCS-only.

v2: move the call to logical_ring_init (Chris)

Fixes: 4a15c75c ("drm/i915: Introduce per-engine workarounds")
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190110013232.8972-2-daniele.ceraolospurio@intel.com

By using the wa lists inside the live driver structures, we won't
catch issues where those are incorrectly setup or corrupted.
To cover this gap, update the workaround framework to allow saving the
wa lists to independent structures and use them in the selftests.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190110013232.8972-1-daniele.ceraolospurio@intel.com
[tursulin: Fixup checkpatch whitespace complaint in memset.]

In the continual quest to reduce the amount of global work required when
submitting requests, replace i915_retire_requests() after allocation
failure to retiring just our ring.

v2: Don't forget the list iteration included an early break, so we would
never throttle on the last request in the ring/timeline.
v3: Use the common ring_retire_requests()

References: 11abf0c5 ("drm/i915: Limit the backpressure for i915_request allocation")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190109215932.26454-1-chris@chris-wilson.co.uk

Add support for PMIC MIPI sequences using the new
intel_soc_pmic_exec_mipi_pmic_seq_element function.

This fixes the DSI LCD panel not lighting up when not initialized by the
GOP (because an external monitor was connected) on GPD win and GPD pocket
devices.

Specifically the LCD panel seems to need GPIO pin 9 on the PMIC to be
driven high, which is done through a PMIC MIPI sequence. Before this commit
if the sequence was not executed by the GOP the pin would stay low causing
the LCD panel to not work. Having the MIPI sequences properly control this
GPIO should also help save some power when the panel is off.

Changes in v2, v3:
-Only changes to other patches in this patch-set

Changes in v4:
-Move decoding of the raw 15 bytes PMIC MIPI sequence element into
 i2c-address, register-address, value and mask into the mipi_exec_pmic()
 function instead of passing the raw data to
 intel_soc_pmic_exec_mipi_pmic_seq_element()
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107111556.4510-5-hdegoede@redhat.com

Most PMIC-s use only a single i2c-address, so after verifying the
i2c-address matches, we can simply pass the call to regmap_update_bits.

This commit adds support for this and hooks this up for the xpower AXP288
PMIC by setting the new pmic_i2c_address field.

This fixes the following errors on display on / off on a Jumper Ezpad
mini 3 and an Onda V80 plus tablet, both of which use the AXP288:

intel_soc_pmic_exec_mipi_pmic_seq_element: Not implemented
intel_soc_pmic_exec_mipi_pmic_seq_element: i2c-addr: 0x34 reg-addr ...
[drm:mipi_exec_pmic [i915]] *ERROR* mipi_exec_pmic failed, error: -95

Instead of these errors on both devices we now correctly turn on / off
DLDO3 (through direct register manipulation). On the Onda V80 plus this
fixes an issue with the backlight being brighter around the borders after
an off / on cycle. This should also help to save some power when the
display is off.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107111556.4510-4-hdegoede@redhat.com

Implement the exec_mipi_pmic_seq_element callback for the CHT Whiskey Cove
PMIC.

On some CHT devices this fixes the LCD panel not lighting up when it was
not initialized by the GOP, because an external monitor was plugged in and
the GOP initialized only the external monitor.
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107111556.4510-3-hdegoede@redhat.com

DSI LCD panels describe an initialization sequence in the Video BIOS
Tables using so called MIPI sequences. One possible element in these
sequences is a PMIC specific element of 15 bytes.

Although this is not really an ACPI opregion, the ACPI opregion code is the
closest thing we have. We need to have support for these PMIC specific MIPI
sequence elements somwhere. Since we already instantiate a special platform
device for Intel PMICs for the ACPI PMIC OpRegion handler to bind to,
with PMIC specific implementations of the OpRegion, the handling of MIPI
sequence PMIC elements fits very well in the ACPI PMIC OpRegion code.

This commit adds a new intel_soc_pmic_exec_mipi_pmic_seq_element()
function, which is to be backed by a PMIC specific
exec_mipi_pmic_seq_element callback. This function will be called by the
i915 code to execture MIPI sequence PMIC elements.
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107111556.4510-2-hdegoede@redhat.com

Needs just a few additional includes here and there.

Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108082709.3748-1-jani.nikula@intel.com

If we haven't shipped and enabled firmware for a particular platform,
there is nothing the user can do about it. Don't scare the user with an
unactionable, unidentifiable warning!

<6> [310.769452] i915 0000:00:02.0: GuC: No firmware known for this platform!
<4> [310.769458] [drm] HuC: No firmware known for this platform!

Unify both GuC/HuC messages to include the device for which we lack the
firmware, and provide the platform name as an aide-memoire.

v2: Move and refine the message to common site of intel_uc_fw_fetch.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190108150246.1471-1-chris@chris-wilson.co.uk

Minimal change to nuke the static buf.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107145149.10069-1-jani.nikula@intel.com

Ignore trying to shrink from i915 if we fail to acquire the struct_mutex
in the shrinker while performing direct-reclaim. The trade-off being
(much) lower latency for non-i915 clients at an increased risk of being
unable to obtain a page from direct-reclaim without hitting the
oom-notifier. The proviso being that we still keep trying to hard
obtain the lock for kswapd so that we can reap under heavy memory
pressure.

v2: Taint all mutexes taken within the shrinker with the struct_mutex
subclass as an early warning system, and drop I915_SHRINK_ACTIVE from
vmap to reduce the number of dangerous paths. We also have to drop
I915_SHRINK_ACTIVE from oom-notifier to be able to make the same claim
that ACTIVE is only used from outside context, which fits in with a
longer strategy of avoiding stalls due to scanning active during
shrinking.

The danger in using the subclass struct_mutex is that we declare
ourselves more knowledgable than lockdep and deprive ourselves of
automatic coverage. Instead, we require ourselves to mark up any mutex
taken inside the shrinker in order to detect lock-inversion, and if we
miss any we are doomed to a deadlock at the worst possible moment.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107115509.12523-1-chris@chris-wilson.co.uk

Generally catch up with 5.0-rc1, and specifically get the changes:

96d4f267 ("Remove 'type' argument from access_ok() function")
0b2c8f8b ("i915: fix missing user_access_end() in page fault exception case")
594cc251 ("make 'user_access_begin()' do 'access_ok()'")
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Merge tag 'topic/drmp-cleanup-2019-01-02' of git://anongit.freedesktop.org/drm/drm-intel into drm-intel-next-queued

Make some drm headers self-contained with includes and forward
declarations.

This topic branch has already been merged to drm-misc-next as commit
1c95f662 ("Merge tag 'topic/drmp-cleanup-2019-01-02' of
git://anongit.freedesktop.org/drm/drm-intel into drm-misc-next"). Now
merge it to drm-intel-next-queued to unblock some further drmP.h cleanup
without having to wait for a backmerge.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87pntfl6pa.fsf@intel.com

Being a mock device, we suffer no DMA restrictions, so set the coherent
mask to 64b.

v2: Fix up mock_huge_selftests

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109243Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107181856.23789-1-chris@chris-wilson.co.uk

Include the total size of closed vma when reporting the per_ctx_stats of
debugfs/i915_gem_objects.

Whilst adjusting the context tracking, note that we can simply use our
list of contexts in i915->contexts rather than circumlocute via
dev->filelist and the per-file context idr, with the result that we can
show objects allocated to different vm (i.e. contexts within a file).

We change the output to show every context of each client, with its own
unique set of objects (for full-ppgtt machines, i.e. gen7+, for older
hardware all objects are in the global gtt and so can not be associated
with a single context). That should result in no loss of information,
and for gen7+, no duplication of active objects.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107115509.12523-2-chris@chris-wilson.co.uk

Haswell also requires the RING_IMR flush for its unique vebox setup to
avoid losing interrupts, as per 476af9c2 ("drm/i915/gen6: Flush
RING_IMR changes before changing the global GT IMR"):

On Baytail, notably, we can still detect missed interrupt syndrome
(where we never spot a completed request). In this case, it can be
alleviated by always keeping the interrupt unmasked, implying that the
interrupt is being lost in the window after modifying the IMR. (This is
the reason we still have the posting reads on enable_irq, if we remove
them we miss interrupts!) Having narrowed the issue down to the IMR,
rather than keeping it always enabled, applying the usual posting
read/flush of the RING_IMR before unmasking the GT IMR also seems to
prevent the missed interrupt. So be it.

References: 476af9c2 ("drm/i915/gen6: Flush RING_IMR changes before changing the global GT IMR")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190105115647.4970-1-chris@chris-wilson.co.uk

CC [M]  drivers/gpu/drm/i915/intel_device_info.o
drivers/gpu/drm/i915/intel_device_info.c:727: warning: Function parameter or member 'dev_priv' not described in 'intel_device_info_runtime_init'
drivers/gpu/drm/i915/intel_device_info.c:727: warning: Excess function parameter 'info' description in 'intel_device_info_runtime_init'
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190105014652.3472-1-chris@chris-wilson.co.uk

Pull more Kbuild updates from Masahiro Yamada:

 - improve boolinit.cocci and use_after_iter.cocci semantic patches

 - fix alignment for kallsyms

 - move 'asm goto' compiler test to Kconfig and clean up jump_label
   CONFIG option

 - generate asm-generic wrappers automatically if arch does not
   implement mandatory UAPI headers

 - remove redundant generic-y defines

 - misc cleanups

* tag 'kbuild-v4.21-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: rename generated .*conf-cfg to *conf-cfg
  kbuild: remove unnecessary stubs for archheader and archscripts
  kbuild: use assignment instead of define ... endef for filechk_* rules
  arch: remove redundant UAPI generic-y defines
  kbuild: generate asm-generic wrappers if mandatory headers are missing
  arch: remove stale comments "UAPI Header export list"
  riscv: remove redundant kernel-space generic-y
  kbuild: change filechk to surround the given command with { }
  kbuild: remove redundant target cleaning on failure
  kbuild: clean up rule_dtc_dt_yaml
  kbuild: remove UIMAGE_IN and UIMAGE_OUT
  jump_label: move 'asm goto' support test to Kconfig
  kallsyms: lower alignment on ARM
  scripts: coccinelle: boolinit: drop warnings on named constants
  scripts: coccinelle: check for redeclaration
  kconfig: remove unused "file" field of yylval union
  nds32: remove redundant kernel-space generic-y
  nios2: remove unneeded HAS_DMA define

Pull perf tooling updates form Ingo Molnar:
 "A final batch of perf tooling changes: mostly fixes and small
  improvements"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  perf session: Add comment for perf_session__register_idle_thread()
  perf thread-stack: Fix thread stack processing for the idle task
  perf thread-stack: Allocate an array of thread stacks
  perf thread-stack: Factor out thread_stack__init()
  perf thread-stack: Allow for a thread stack array
  perf thread-stack: Avoid direct reference to the thread's stack
  perf thread-stack: Tidy thread_stack__bottom() usage
  perf thread-stack: Simplify some code in thread_stack__process()
  tools gpio: Allow overriding CFLAGS
  tools power turbostat: Override CFLAGS assignments and add LDFLAGS to build command
  tools thermal tmon: Allow overriding CFLAGS assignments
  tools power x86_energy_perf_policy: Override CFLAGS assignments and add LDFLAGS to build command
  perf c2c: Increase the HITM ratio limit for displayed cachelines
  perf c2c: Change the default coalesce setup
  perf trace beauty ioctl: Beautify USBDEVFS_ commands
  perf trace beauty: Export function to get the files for a thread
  perf trace: Wire up ioctl's USBDEBFS_ cmd table generator
  perf beauty ioctl: Add generator for USBDEVFS_ ioctl commands
  tools headers uapi: Grab a copy of usbdevice_fs.h
  perf trace: Store the major number for a file when storing its pathname
  ...

The semantics of what "in core" means for the mincore() system call are
somewhat unclear, but Linux has always (since 2.3.52, which is when
mincore() was initially done) treated it as "page is available in page
cache" rather than "page is mapped in the mapping".

The problem with that traditional semantic is that it exposes a lot of
system cache state that it really probably shouldn't, and that users
shouldn't really even care about.

So let's try to avoid that information leak by simply changing the
semantics to be that mincore() counts actual mapped pages, not pages
that might be cheaply mapped if they were faulted (note the "might be"
part of the old semantics: being in the cache doesn't actually guarantee
that you can access them without IO anyway, since things like network
filesystems may have to revalidate the cache before use).

In many ways the old semantics were somewhat insane even aside from the
information leak issue.  From the very beginning (and that beginning is
a long time ago: 2.3.52 was released in March 2000, I think), the code
had a comment saying

  Later we can get more picky about what "in core" means precisely.

and this is that "later".  Admittedly it is much later than is really
comfortable.

NOTE! This is a real semantic change, and it is for example known to
change the output of "fincore", since that program literally does a
mmmap without populating it, and then doing "mincore()" on that mapping
that doesn't actually have any pages in it.

I'm hoping that nobody actually has any workflow that cares, and the
info leak is real.

We may have to do something different if it turns out that people have
valid reasons to want the old semantics, and if we can limit the
information leak sanely.

Cc: Kevin Easton <kevin@guarana.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Masatake YAMATO <yamato@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>