Save RING_HEAD into vgpu reg when vgpu switched out and report
it's value back to guest.

v6: addressed comment for ring head wrap count support. (Zhenyu)
v5: ring head wrap count support.
v4: updated HEAD/TAIL with guest value, not host value. (Yan Zhao)
v3: save RING HEAD/TAIL vgpu reg in save_ring_hw_state. (Zhenyu Wang)
v2: save RING_TAIL as well during vgpu mmio switch to meet ring_is_idle
condition. (Fred Gao)
v1: based on input from Weinan. (Weinan Li)

[zhenyuw: Include this fix for possible future guest kernel that
would utilize RING_HEAD for hangcheck.]
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Xiaolin Zhang <xiaolin.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Instead of updating by MMIO write, all of the wa regs are initialized by
wa_ctx. From host side, it should make this behavior as expected, add
'F_CMD_ACCESS' flag to these regs and allow access by commands.

[  123.557608] gvt: vgpu 2: srm access to non-render register (b11c)
[  123.563728] gvt: vgpu 2: MI_STORE_REGISTER_MEM handler error
[  123.569409] gvt: vgpu 2: cmd parser error
[  123.573424] 0x0
[  123.573425] 0x24

[  123.578686] gvt: vgpu 2: scan workload error
[  123.582958] GVT Internal error  for the guest
[  123.587317] Now vgpu 2 will enter failsafe mode.
[  123.591938] gvt: vgpu 2: failed to submit desc 0
[  123.596557] gvt: vgpu 2: fail submit workload on ring 0
[  123.601786] gvt: vgpu 2: fail to emulate MMIO write 00002230 len 4
Acked-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Weinan Li <weinan.z.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

The klocwork static code analyzer complains about using pointer after
being freed, because further we pass it to the gvt_vgpu_err() function.
Assign pointer to be NULL intentionaly, to meet requirements of the code
analyzer.

This patch fixed the issue #648 reported as error by klocwork.
Acked-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Aleksei Gimbitskii <aleksei.gimbitskii@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Static code analyzer warns that index value for scratch_pt may be equal
to -1. Index value type is intel_gvt_gtt_type_t, so it may be any number
at range -1 to 17. Check first if cur_pt_type and cur_pt_type+1 is valid
values.

v2:
 - Print some error messages if page table type is invalid. (Colin Xu)

v4:
 - Print cur_pt_type in error message. (Colin Xu)

This patch fixed the critial issue #422 reported by klocwork.
Acked-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Aleksei Gimbitskii <aleksei.gimbitskii@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Fix the length value of VEB_DI_IECP.

Fixes: be1da707 ("drm/i915/gvt: vGPU command scanner")
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Gao, Fred <fred.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

The vgpu ggtt range should be in vgpu aperture or hidden range. This
patch enforce begin and end address check and guarantee both of them are
in the valid range.

For size=0, it will regress to vgpu_gmadr_is_valid(), will refine
this usage in a later fix.

Fixes: 2707e444 ("drm/i915/gvt: vGPU graphics memory virtualization")
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Enter failsafe if vgpu tries to change CSFE_CHICKEN1_REG setting
which is controlled by host.
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Enter failsafe if vgpu tries to change GFX_MODE controlled by host.
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Host prints below warning message when guest running some application:
"gvt: vgpu(1) Invalid FORCE_NONPRIV write 2754 at 24f0".
"gvt: vgpu(1) Invalid FORCE_NONPRIV write 28a0 at 24f0".

Registers 0x2754 and 0x28a0 are required by guest so add to whitelist.
Signed-off-by: Colin Xu <colin.xu@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Stack struct intel_gvt_gtt_entry value needs to be initialized before
being used, as the fields may contain garbage values.

W/o this patch, set_ggtt_entry prints:
-------------------------------------
274.046840: set_ggtt_entry: vgpu1:set ggtt entry 0x9bed8000ffffe900
274.046846: set_ggtt_entry: vgpu1:set ggtt entry 0xe55df001
274.046852: set_ggtt_entry: vgpu1:set ggtt entry 0x9bed8000ffffe900

0x9bed8000 is the stack grabage.

W/ this patch, set_ggtt_entry prints:
------------------------------------
274.046840: set_ggtt_entry: vgpu1:set ggtt entry 0xffffe900
274.046846: set_ggtt_entry: vgpu1:set ggtt entry 0xe55df001
274.046852: set_ggtt_entry: vgpu1:set ggtt entry 0xffffe900

v2:
- Initialize during declaration. (Zhenyu)

Fixes: 7598e870 ("drm/i915/gvt: Missed to cancel dma map for ggtt entries")
Cc: stable@vger.kernel.org # v4.20+
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

"ret" is uninitialized on this path but it should be -EINVAL.

Fixes: 930c8dfe ("drm/i915/gvt: Check if get_next_pt_type() always returns a valid value")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

the vGPU write on TRTTE and 0x4dfc is now write to vreg first. their
values all be restored hardware when context switching.

Fixes: e39c5add ("drm/i915/gvt: vGPU MMIO virtualization")
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

0x4dfc is in-context mmio for gen9+, but each vm have different settings
need to add it to save-restore list along with other trtt registers

Fixes: 17865713 ("drm/i915/gvt: vGPU context switch")
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

TRVATTL3PTRDW(0x4de0-0x4de4), TRNULLDETCT(0x4de8), TRINVTILEDETCT(0x4dec),
TRTTE(0x4df0), TRVADR(0x4df4) are in-context mmios for gen9+

Fixes: 17865713 ("drm/i915/gvt: vGPU context switch")
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

for restore-inhibit context, hardware will not load in-context mmios
(engine context part) to hardware, but hardware will save the mmio
values in hardware back to context image. So, in order to save correct
values of vGPU back to context image, values of vGPU mmios have to be
loaded into hardware first for restore-inhibit context.

In this patch, the mechanism is applied to all gen9 platform.

The reason excluding gen8 platforms is only because of lacking of testing
on those platforms.

v3: for mocs registers, goto in-context mmios save-restore path for skl
platform as well (weinan li)
v2: update vreg when scanning indirect context for inhibit context for
gen9

Cc: Weinan Li <weinan.z.li@intel.com>
Acked-by: Weinan Li <weinan.z.li@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

"To track whether a request has started on HW, we can emit a breadcrumb at
the beginning of the request and check its timeline's HWSP to see if the
breadcrumb has advanced past the start of this request." It means all the
request which timeline's has_init_breadcrumb is true, then the
emit_init_breadcrumb process must have before emitting the real commands,
otherwise, the scheduler might get a wrong state of this request during
reset. If the request is exactly the guilty one, the scheduler won't
terminate it with the wrong state. To avoid this, do emit_init_breadcrumb
for all the requests from gvt.

v2: cc to stable kernel

Fixes: 85474441 ("drm/i915: Identify active requests")
Cc: stable@vger.kernel.org
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Weinan <weinan.z.li@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

In commit b7404c7e ("drm/i915: Bump ready tasks ahead of
busywaits"), I tried cutting a corner in order to not install a signal
for each of our dependencies, and only listened to requests on which we
were intending to busywait. The compromise that was made was that
instead of then being able to promote the request with a full
NOSEMAPHORE like its non-busywaiting brethren, as we had not ensured we
had cleared the semaphore chain, we settled for only using the NEWCLIENT
boost. With an over saturated system with multiple NEWCLIENTS in flight
at any time, this was found to be an inadequate promotion and left us
with a much poorer scheduling order than prior to using semaphores.

The outcome of this patch, is that all requests have NOSEMAPHORE
priority when they have no dependencies and are ready to run and not
busywait, restoring the pre-semaphore ordering on saturated systems.

We can demonstrate the effect of poor scheduling order by oversaturating
the system using gem_wsim on a system with multiple vcs engines
(i.e running the same workloads across more clients than required for
peak throughput, e.g. media_load_balance_17i7.wsim -c4 -b context):

x v5.1 (normalized)
+ tip
* fix
+------------------------------------------------------------------------+
|                                                                    x   |
|                                                                    x   |
|                                                                    x   |
|                                                                    x   |
|                                                                   %x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %%x   |
|                                                                  %#x   |
|                                                                  %#x   |
|                                                                  %#x   |
|                                                                  %#x   |
|                                                                  %#x   |
|         +                                                        %#xx  |
|         +                                                        %#xx  |
|         +                                                       %%#xx  |
|         +                                                       %%#xx  |
|         +                                                       %%#xx  |
|         +                                                       %%#xx  |
|         +                                                       %%##x  |
|         +++                                                     %%##x  |
|         +++                                                     %%##x  |
|         +++                                                     %%##x  |
|        ++++                                                     %%##x  |
|        ++++                                                     %%##x  |
|        ++++                                                     %%##xx |
|        ++++                                                     %###xx |
|        ++++                                                     %###xx |
|        ++++                                                     %###xx |
|        ++++                                                     %###xx |
|        ++++ +                                                   %#O#xx |
|        ++++ +                                                   %#O#xx |
|        ++++++ +                                                 %#O#xx |
|       ++++++++++                                                %OOOxxx|
|       ++++++++++       +                                       %#OOO#xx|
|     + ++++++++++++ ++ +++++    +                        ++    @@OOOO#xx|
|                                                                   |A_| |
||__________M_______A____________________|                               |
|                                                                 |A_|   |
+------------------------------------------------------------------------+
    N           Min           Max        Median           Avg        Stddev
x 120       0.99456       1.00628      0.999985     1.0001545  0.0024387139
+ 120      0.873021       1.00037      0.884134    0.90148752   0.039190862
Difference at 99.5% confidence
	-0.098667 +/- 0.0110762
	-9.86517% +/- 1.10745%
	(Student's t, pooled s = 0.0277657)
% 120      0.990207       1.00165     0.9970265    0.99699748     0.0021024
Difference at 99.5% confidence
	-0.003157 +/- 0.000908245
	-0.315651% +/- 0.0908105%
	(Student's t, pooled s = 0.00227678)

Fixes: b7404c7e ("drm/i915: Bump ready tasks ahead of busywaits")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Dmitry Rogozhkin <dmitry.v.rogozhkin@intel.com>
Cc: Dmitry Ermilov <dmitry.ermilov@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190515130052.4475-2-chris@chris-wilson.co.uk
(cherry picked from commit 17db337f)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Commit 1413b2bc ("drm/i915: Trim NEWCLIENT boosting") had the
intended consequence of not allowing a sequence of work that merely
crossed into a new engine the privilege to be promoted to NEWCLIENT
status. It also had the unintended consequence of actually making
NEWCLIENT effective on heavily oversubscribed transcode machines and
impacting upon their throughput.

If we consider a client packet composed of (rcsA, rcsB, vcs) and 30 of
those clients, using the NEWCLIENT boost that will be scheduled as

	rcsA x 30, (rcsB, vcs) x 30

where as before it would have been

	(rcsA, rcsB, vcs) x 30

That is with NEWCLIENT only boosting the first request of each client,
we would execute all rcsA requests prior to running on the vcs engines;
acruing a lot of dead time as compared to the previous case where the
vcs engine would be started in parallel to processing the second client.

The previous patch has the effect of delaying submission until it is
required by a third party (either the user with an explicit wait, or by
another client/engine). We reduce the NEWCLIENT bump to a mere WAIT,
which has the effect of removing its preemptive grant and reducing it to
the same level as any other user interaction -- that it will not be
promoted above the interengine dependencies, and so preventing NEWCLIENTS
from starving other engines. This a large nerf to the rrul properties of
the current NEWCLIENT, but it still does give prioritised submission to
new requests from light workloads.

References: b16c7651 ("drm/i915: Priority boost for new clients")
Fixes: 1413b2bc ("drm/i915: Trim NEWCLIENT boosting") # customer impact
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Dmitry Rogozhkin <dmitry.v.rogozhkin@intel.com>
Cc: Dmitry Ermilov <dmitry.ermilov@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190515130052.4475-4-chris@chris-wilson.co.uk
(cherry picked from commit 68fc728b)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

The handling of the no-preemption priority level imposes the restriction
that we need to maintain the implied ordering even though preemption is
disabled. Otherwise we may end up with an AB-BA deadlock across multiple
engine due to a real preemption event reordering the no-preemption
WAITs. To resolve this issue we currently promote all requests to WAIT
on unsubmission, however this interferes with the timeslicing
requirement that we do not apply any implicit promotion that will defeat
the round-robin timeslice list. (If we automatically promote the active
request it will go back to the head of the queue and not the tail!)

So we need implicit promotion to prevent reordering around semaphores
where we are not allowed to preempt, and we must avoid implicit
promotion on unsubmission. So instead of at unsubmit, if we apply that
implicit promotion on adding the dependency, we avoid the semaphore
deadlock and we also reduce the gains made by the promotion for user
space waiting. Furthermore, by keeping the earlier dependencies at a
higher level, we reduce the search space for timeslicing without
altering runtime scheduling too badly (no dependencies at all will be
assigned a higher priority for rrul).

v2: Limit the bump to external edges (as originally intended) i.e.
between contexts and out to the user.

Testcase: igt/gem_concurrent_blit
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190515130052.4475-3-chris@chris-wilson.co.uk
(cherry picked from commit 6e7eb7a8)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

To simplify the next patch, update bump_priority and schedule to accept
the internal i915_sched_ndoe directly and not expect a request pointer.

add/remove: 0/0 grow/shrink: 2/1 up/down: 8/-15 (-7)
Function                                     old     new   delta
i915_schedule_bump_priority                  109     113      +4
i915_schedule                                 50      54      +4
__i915_schedule                              922     907     -15

v2: Adopt node for the old rq local, since it no longer is a request but
the origin node.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190513120102.29660-2-chris@chris-wilson.co.uk
(cherry picked from commit 52c76fb1)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

To avoid pulling in a forward declaration in the next patch, move the
i915_sched_node handling to after the main dfs of the scheduler.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190513120102.29660-1-chris@chris-wilson.co.uk
(cherry picked from commit 5ae87063)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Pull UBIFS fixes from Richard Weinberger:

 - build errors wrt xattrs

 - mismerge which lead to a wrong Kconfig ifdef

 - missing endianness conversion

* tag 'upstream-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubifs: Convert xattr inum to host order
  ubifs: Use correct config name for encryption
  ubifs: Fix build error without CONFIG_UBIFS_FS_XATTR

Merge yet more updates from Andrew Morton:
 "A few final bits:

   - large changes to vmalloc, yielding large performance benefits

   - tweak the console-flush-on-panic code

   - a few fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  panic: add an option to replay all the printk message in buffer
  initramfs: don't free a non-existent initrd
  fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going into workqueue when umount
  mm/compaction.c: correct zone boundary handling when isolating pages from a pageblock
  mm/vmap: add DEBUG_AUGMENT_LOWEST_MATCH_CHECK macro
  mm/vmap: add DEBUG_AUGMENT_PROPAGATE_CHECK macro
  mm/vmalloc.c: keep track of free blocks for vmap allocation

Pull more Kbuild updates from Masahiro Yamada:

 - remove unneeded use of cc-option, cc-disable-warning, cc-ldoption

 - exclude tracked files from .gitignore

 - re-enable -Wint-in-bool-context warning

 - refactor samples/Makefile

 - stop building immediately if syncconfig fails

 - do not sprinkle error messages when $(CC) does not exist

 - move arch/alpha/defconfig to the configs subdirectory

 - remove crappy header search path manipulation

 - add comment lines to .config to clarify the end of menu blocks

 - check uniqueness of module names (adding new warnings intentionally)

* tag 'kbuild-v5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (24 commits)
  kconfig: use 'else ifneq' for Makefile to improve readability
  kbuild: check uniqueness of module names
  kconfig: Terminate menu blocks with a comment in the generated config
  kbuild: add LICENSES to KBUILD_ALLDIRS
  kbuild: remove 'addtree' and 'flags' magic for header search paths
  treewide: prefix header search paths with $(srctree)/
  media: prefix header search paths with $(srctree)/
  media: remove unneeded header search paths
  alpha: move arch/alpha/defconfig to arch/alpha/configs/defconfig
  kbuild: terminate Kconfig when $(CC) or $(LD) is missing
  kbuild: turn auto.conf.cmd into a mandatory include file
  .gitignore: exclude .get_maintainer.ignore and .gitattributes
  kbuild: add all Clang-specific flags unconditionally
  kbuild: Don't try to add '-fcatch-undefined-behavior' flag
  kbuild: add some extra warning flags unconditionally
  kbuild: add -Wvla flag unconditionally
  arch: remove dangling asm-generic wrappers
  samples: guard sub-directories with CONFIG options
  kbuild: re-enable int-in-bool-context warning
  MAINTAINERS: kbuild: Add pattern for scripts/*vmlinux*
  ...

Pull i2c updates from Wolfram Sang:
 "Some I2C core API additions which are kind of simple but enhance error
  checking for users a lot, especially by returning errno now.

  There are wrappers to still support the old API but it will be removed
  once all users are converted"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: core: add device-managed version of i2c_new_dummy
  i2c: core: improve return value handling of i2c_new_device and i2c_new_dummy

Pull ext4 fixes from Ted Ts'o:
 "Some bug fixes, and an update to the URL's for the final version of
  Unicode 12.1.0"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: avoid panic during forced reboot due to aborted journal
  ext4: fix block validity checks for journal inodes using indirect blocks
  unicode: update to Unicode 12.1.0 final
  unicode: add missing check for an error return from utf8lookup()
  ext4: fix miscellaneous sparse warnings
  ext4: unsigned int compared against zero
  ext4: fix use-after-free in dx_release()
  ext4: fix data corruption caused by overlapping unaligned and aligned IO
  jbd2: fix potential double free
  ext4: zero out the unused memory region in the extent tree block

Pull cifs fixes from Steve French:
 "Minor cleanup and fixes, one for stable, four rdma (smbdirect)
  related. Also adds SEEK_HOLE support"

* tag '5.2-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: add support for SEEK_DATA and SEEK_HOLE
  Fixed https://bugzilla.kernel.org/show_bug.cgi?id=202935 allow write on the same file
  cifs: Allocate memory for all iovs in smb2_ioctl
  cifs: Don't match port on SMBDirect transport
  cifs:smbd Use the correct DMA direction when sending data
  cifs:smbd When reconnecting to server, call smbd_destroy() after all MIDs have been called
  cifs: use the right include for signal_pending()
  smb3: trivial cleanup to smb2ops.c
  cifs: cleanup smb2ops.c and normalize strings
  smb3: display session id in debug data

Pull perf tooling updates from Ingo Molnar:
 "perf.data:

   - Streaming compression of perf ring buffer into
     PERF_RECORD_COMPRESSED user space records, resulting in ~3-5x
     perf.data file size reduction on variety of tested workloads what
     saves storage space on larger server systems where perf.data size
     can easily reach several tens or even hundreds of GiBs, especially
     when profiling with DWARF-based stacks and tracing of context
     switches.

  perf record:

   - Improve -user-regs/intr-regs suggestions to overcome errors

  perf annotate:

   - Remove hist__account_cycles() from callback, speeding up branch
     processing (perf record -b)

  perf stat:

   - Add a 'percore' event qualifier, e.g.: -e
     cpu/event=0,umask=0x3,percore=1/, that sums up the event counts for
     both hardware threads in a core.

     We can already do this with --per-core, but it's often useful to do
     this together with other metrics that are collected per hardware
     thread.

     I.e. now its possible to do this per-event, and have it mixed with
     other events not aggregated by core.

  arm64:

   - Map Brahma-B53 CPUID to cortex-a53 events.

   - Add Cortex-A57 and Cortex-A72 events.

  csky:

   - Add DWARF register mappings for libdw, allowing --call-graph=dwarf
     to work on the C-SKY arch.

  x86:

   - Add support for recording and printing XMM registers, available,
     for instance, on Icelake.

   - Add uncore_upi (Intel's "Ultra Path Interconnect" events) JSON
     support. UPI replaced the Intel QuickPath Interconnect (QPI) in
     Xeon Skylake-SP.

  Intel PT:

   - Fix instructions sampling rate.

   - Timestamp fixes.

   - Improve exported-sql-viewer GUI, allowing, for instance, to
     copy'n'paste the trees, useful for e-mailing"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (73 commits)
  perf stat: Support 'percore' event qualifier
  perf stat: Factor out aggregate counts printing
  perf tools: Add a 'percore' event qualifier
  perf docs: Add description for stderr
  perf intel-pt: Fix sample timestamp wrt non-taken branches
  perf intel-pt: Fix improved sample timestamp
  perf intel-pt: Fix instructions sampling rate
  perf regs x86: Add X86 specific arch__intr_reg_mask()
  perf parse-regs: Add generic support for arch__intr/user_reg_mask()
  perf parse-regs: Split parse_regs
  perf vendor events arm64: Add Cortex-A57 and Cortex-A72 events
  perf vendor events arm64: Map Brahma-B53 CPUID to cortex-a53 events
  perf vendor events arm64: Remove [[:xdigit:]] wildcard
  perf jevents: Remove unused variable
  perf test zstd: Fixup verbose mode output
  perf tests: Implement Zstd comp/decomp integration test
  perf inject: Enable COMPRESSED record decompression
  perf report: Implement perf.data record decompression
  perf record: Implement -z,--compression_level[=<n>] option
  perf report: Add stub processing of compressed events for -D
  ...

Pull clocksource updates from Ingo Molnar:
 "Misc clocksource/clockevent driver updates that came in a bit late but
  are ready for v5.2"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  misc: atmel_tclib: Do not probe already used TCBs
  clocksource/drivers/timer-atmel-tcb: Convert tc_clksrc_suspend|resume() to static
  clocksource/drivers/tcb_clksrc: Rename the file for consistency
  clocksource/drivers/timer-atmel-pit: Rework Kconfig option
  clocksource/drivers/tcb_clksrc: Move Kconfig option
  ARM: at91: Implement clocksource selection
  clocksource/drivers/tcb_clksrc: Use tcb as sched_clock
  clocksource/drivers/tcb_clksrc: Stop depending on atmel_tclib
  ARM: at91: move SoC specific definitions to SoC folder
  clocksource/drivers/timer-milbeaut: Cleanup common register accesses
  clocksource/drivers/timer-milbeaut: Add shutdown function
  clocksource/drivers/timer-milbeaut: Fix to enable one-shot timer
  clocksource/drivers/tegra: Rework for compensation of suspend time
  clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804
  clocksource/drivers/sun4i: Add a compatible for suniv
  dt-bindings: timer: Add Allwinner suniv timer

Pull IRQ chip updates from Ingo Molnar:
 "A late irqchips update:

   - New TI INTR/INTA set of drivers

   - Rewrite of the stm32mp1-exti driver as a platform driver

   - Update the IOMMU MSI mapping API to be RT friendly

   - A number of cleanups and other low impact fixes"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  iommu/dma-iommu: Remove iommu_dma_map_msi_msg()
  irqchip/gic-v3-mbi: Don't map the MSI page in mbi_compose_m{b, s}i_msg()
  irqchip/ls-scfg-msi: Don't map the MSI page in ls_scfg_msi_compose_msg()
  irqchip/gic-v3-its: Don't map the MSI page in its_irq_compose_msi_msg()
  irqchip/gicv2m: Don't map the MSI page in gicv2m_compose_msi_msg()
  iommu/dma-iommu: Split iommu_dma_map_msi_msg() in two parts
  genirq/msi: Add a new field in msi_desc to store an IOMMU cookie
  arm64: arch_k3: Enable interrupt controller drivers
  irqchip/ti-sci-inta: Add msi domain support
  soc: ti: Add MSI domain bus support for Interrupt Aggregator
  irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver
  dt-bindings: irqchip: Introduce TISCI Interrupt Aggregator bindings
  irqchip/ti-sci-intr: Add support for Interrupt Router driver
  dt-bindings: irqchip: Introduce TISCI Interrupt router bindings
  gpio: thunderx: Use the default parent apis for {request,release}_resources
  genirq: Introduce irq_chip_{request,release}_resource_parent() apis
  firmware: ti_sci: Add helper apis to manage resources
  firmware: ti_sci: Add RM mapping table for am654
  firmware: ti_sci: Add support for IRQ management
  firmware: ti_sci: Add support for RM core ops
  ...

Pull EFI fix from Ingo Molnar:
 "Fix an EFI-fb regression that affects certain x86 systems"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  fbdev/efifb: Ignore framebuffer memmap entries that lack any memory types

Pull core fixes from Ingo Molnar:
 "This fixes a particularly thorny munmap() bug with MPX, plus fixes a
  host build environment assumption in objtool"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Allow AR to be overridden with HOSTAR
  x86/mpx, mm/core: Fix recursive munmap() corruption

Pull ARM SoC late updates from Olof Johansson:
 "This is some material that we picked up into our tree late. Most of it
  are smaller fixes and additions, some defconfig updates due to recent
  development, etc.

  Code-wise the largest portion is a series of PM updates for the at91
  platform, and those have been in linux-next a while through the at91
  tree before we picked them up"

* tag 'armsoc-late' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (29 commits)
  arm64: dts: sprd: Add clock properties for serial devices
  Opt out of scripts/get_maintainer.pl
  ARM: ixp4xx: Remove duplicated include from common.c
  soc: ixp4xx: qmgr: Fix an NULL vs IS_ERR() check in probe
  arm64: tegra: Disable XUSB support on Jetson TX2
  arm64: tegra: Enable SMMU translation for PCI on Tegra186
  arm64: tegra: Fix insecure SMMU users for Tegra186
  arm64: tegra: Select ARM_GIC_PM
  amba: tegra-ahb: Mark PM functions as __maybe_unused
  ARM: dts: logicpd-som-lv: Fix MMC1 card detect
  ARM: mvebu: drop return from void function
  ARM: mvebu: prefix coprocessor operand with p
  ARM: mvebu: drop unnecessary label
  ARM: mvebu: fix a leaked reference by adding missing of_node_put
  ARM: socfpga_defconfig: enable LTC2497
  ARM: mvebu: kirkwood: remove error message when retrieving mac address
  ARM: at91: sama5: make ov2640 as a module
  ARM: OMAP1: ams-delta: fix early boot crash when LED support is disabled
  ARM: at91: remove HAVE_FB_ATMEL for sama5 SoC as they use DRM
  soc/fsl/qe: Fix an error code in qe_pin_request()
  ...

Pull powerpc fixes from Michael Ellerman:
 "One fix going back to stable, for a bug on 32-bit introduced when we
  added support for THREAD_INFO_IN_TASK.

  A fix for a typo in a recent rework of our hugetlb code that leads to
  crashes on 64-bit when using hugetlbfs with a 4K PAGE_SIZE.

  Two fixes for our recent rework of the address layout on 64-bit hash
  CPUs, both only triggered when userspace tries to access addresses
  outside the user or kernel address ranges.

  Finally a fix for a recently introduced double free in an error path
  in our cacheinfo code.

  Thanks to: Aneesh Kumar K.V, Christophe Leroy, Sachin Sant, Tobin C.
  Harding"

* tag 'powerpc-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/cacheinfo: Remove double free
  powerpc/mm/hash: Fix get_region_id() for invalid addresses
  powerpc/mm: Drop VM_BUG_ON in get_region_id()
  powerpc/mm: Fix crashes with hugepages & 4K pages
  powerpc/32s: fix flush_hash_pages() on SMP

Pull a few more MIPS updates from Paul Burton:
 "Some SGI IP27 specific PCI rework and a batch of fixes:

   - A build fix for BMIPS5000 configurations with
     CONFIG_HW_PERF_EVENTS=y, which also neatly removes some #ifdefery.

   - A fix to report supported ISAs correctly on older Ingenic SoCs
     which incorrectly indicate MIPSr2 support in their cop0 Config
     register.

   - Some PCI modernization for SGI IP27 systems as part of ongoing work
     to support some other SGI systems.

   - A fix allowing use of appended DTB files with generic kernels.

   - DMA mask fixes for SGI IP22 & Alchemy systems"

* tag 'mips_5.2_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Alchemy: add DMA masks for on-chip ethernet
  MIPS: SGI-IP22: provide missing dma_mask/coherent_dma_mask
  generic: fix appended dtb support
  MIPS: SGI-IP27: abstract chipset irq from bridge
  MIPS: SGI-IP27: use generic PCI driver
  MIPS: Fix Ingenic SoCs sometimes reporting wrong ISA
  MIPS: perf: Fix build with CONFIG_CPU_BMIPS5000 enabled

Merge tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V updates from Palmer Dabbelt:
 "This contains an assortment of RISC-V related patches that I'd like to
  target for the 5.2 merge window. Most of the patches are cleanups, but
  there are a handful of user-visible changes:

   - The nosmp and nr_cpus command-line arguments are now supported,
     which work like normal.

   - The SBI console no longer installs itself as a preferred console,
     we rely on standard mechanisms (/chosen, command-line, hueristics)
     instead.

   - sfence_remove_sfence_vma{,_asid} now pass their arguments along to
     the SBI call.

   - Modules now support BUG().

   - A missing sfence.vma during boot has been added. This bug only
     manifests during boot.

   - The arch/riscv support for SiFive's L2 cache controller has been
     merged, which should un-block the EDAC framework work.

  I've only tested this on QEMU again, as I didn't have time to get
  things running on the Unleashed. The latest master from this morning
  merges in cleanly and passes the tests as well"

* tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (31 commits)
  riscv: fix locking violation in page fault handler
  RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs
  RISC-V: Add DT documentation for SiFive L2 Cache Controller
  RISC-V: Avoid using invalid intermediate translations
  riscv: Support BUG() in kernel module
  riscv: Add the support for c.ebreak check in is_valid_bugaddr()
  riscv: support trap-based WARN()
  riscv: fix sbi_remote_sfence_vma{,_asid}.
  riscv: move switch_mm to its own file
  riscv: move flush_icache_{all,mm} to cacheflush.c
  tty: Don't force RISCV SBI console as preferred console
  RISC-V: Access CSRs using CSR numbers
  RISC-V: Add interrupt related SCAUSE defines in asm/csr.h
  RISC-V: Use tabs to align macro values in asm/csr.h
  RISC-V: Fix minor checkpatch issues.
  RISC-V: Support nr_cpus command line option.
  RISC-V: Implement nosmp commandline option.
  RISC-V: Add RISC-V specific arch_match_cpu_phys_id
  riscv: vdso: drop unnecessary cc-ldoption
  riscv: call pm_power_off from machine_halt / machine_power_off
  ...

'ifeq ... else ifneq ... endif' notation is supported by GNU Make 3.81
or later, which is the requirement for building the kernel since
commit 37d69ee3 ("docs: bump minimal GNU Make version to 3.81").

Use it to improve the readability.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Currently on panic, kernel will lower the loglevel and print out pending
printk msg only with console_flush_on_panic().

Add an option for users to configure the "panic_print" to replay all
dmesg in buffer, some of which they may have never seen due to the
loglevel setting, which will help panic debugging .

[feng.tang@intel.com: keep the original console_flush_on_panic() inside panic()]
  Link: http://lkml.kernel.org/r/1556199137-14163-1-git-send-email-feng.tang@intel.com
[feng.tang@intel.com: use logbuf lock to protect the console log index]
  Link: http://lkml.kernel.org/r/1556269868-22654-1-git-send-email-feng.tang@intel.com
Link: http://lkml.kernel.org/r/1556095872-36838-1-git-send-email-feng.tang@intel.comSigned-off-by: Feng Tang <feng.tang@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since commit 54c7a891 ("initramfs: free initrd memory if opening
/initrd.image fails"), the kernel has unconditionally attempted to free
the initrd even if it doesn't exist.

In the non-existent case this causes a boot-time splat if
CONFIG_DEBUG_VIRTUAL is enabled due to a call to virt_to_phys() with a
NULL address.

Instead we should check that the initrd actually exists and only attempt
to free it if it does.

Link: http://lkml.kernel.org/r/20190516143125.48948-1-steven.price@arm.com
Fixes: 54c7a891 ("initramfs: free initrd memory if opening /initrd.image fails")
Signed-off-by: Steven Price <steven.price@arm.com>
Reported-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>