Add Kconfig, Makefile and basic instruction support for x86 IBT.

(Ab)use __DISABLE_EXPORTS to disable IBT since it's already employed
to mark compressed and purgatory. Additionally mark realmode with it
as well to avoid inserting ENDBR instructions there. While ENDBR is
technically a NOP, inserting them was causing some grief due to code
growth. There's also a problem with using __noendbr in code compiled
without -fcf-protection=branch.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.519875203@infradead.org

Currently WARN_FUNC() either prints func+off and failing that prints
sec+off, add an intermediate sym+off. This is useful when playing
around with entry code.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.461283840@infradead.org

The current annotation relies on not running objtool on the file; this
won't work when running objtool on vmlinux.o. Instead explicitly mark
__efi64_thunk() to be ignored.

This preserves the status quo, which is somewhat unfortunate. Luckily
this code is hardly ever used.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.402118218@infradead.org

Ignore all INT3 instructions for unreachable code warnings, similar to NOP.
This allows using INT3 for various paddings instead of NOPs.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.343312938@infradead.org

Add a --dry-run argument to skip writing the modifications. This is
convenient for debugging.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NMiroslav Benes <mbenes@suse.cz>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.282720146@infradead.org

Without CONFIG_HAVE_STATIC_CALL_INLINE there's no point in creating
the .static_call_sites section and it's related symbols.
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.223798256@infradead.org

Enjoy the cleanups and avoid conflicts vs linkage
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>

The ENQCMD instruction implicitly accesses the PASID_MSR to fill in the
pasid field of the descriptor being submitted to an accelerator. But
there is no precise (and stable across kernel changes) point at which
the PASID_MSR is updated from the value for one task to the next.

Kernel code that uses accelerators must always use the ENQCMDS instruction
which does not access the PASID_MSR.

Check for use of the ENQCMD instruction in the kernel and warn on its
usage.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NTony Luck <tony.luck@intel.com>
Acked-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220207230254.3342514-11-fenghua.yu@intel.comSigned-off-by: NPeter Zijlstra <peterz@infradead.org>

Pull x86 fixes from Borislav Petkov:

 - Free shmem backing storage for SGX enclave pages when those are
   swapped back into EPC memory

 - Prevent do_int3() from being kprobed, to avoid recursion

 - Remap setup_data and setup_indirect structures properly when
   accessing their members

 - Correct the alternatives patching order for modules too

* tag 'x86_urgent_for_v5.17_rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sgx: Free backing memory after faulting the enclave page
  x86/traps: Mark do_int3() NOKPROBE_SYMBOL
  x86/boot: Add setup_indirect support in early_memremap_is_setup_data()
  x86/boot: Fix memremap of setup_indirect structures
  x86/module: Fix the paravirt vs alternative order

Merge tag 'perf-tools-fixes-for-v5.17-2022-03-12' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Fix event parser error for hybrid systems

 - Fix NULL check against wrong variable in 'perf bench' and in the
   parsing code

 - Update arm64 KVM headers from the kernel sources

 - Sync cpufeatures header with the kernel sources

* tag 'perf-tools-fixes-for-v5.17-2022-03-12' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf parse: Fix event parser error for hybrid systems
  perf bench: Fix NULL check against wrong variable
  perf parse-events: Fix NULL check against wrong variable
  tools headers cpufeatures: Sync with the kernel sources
  tools kvm headers arm64: Update KVM headers from the kernel sources

Pull drm kconfig fix from Dave Airlie:
 "Thorsten pointed out this had fallen down the cracks and was in -next
  only, I've picked it out, fixed up it's Fixes: line.

   - fix regression in Kconfig"

* tag 'drm-fixes-2022-03-12' of git://anongit.freedesktop.org/drm/drm:
  drm/panel: Select DRM_DP_HELPER for DRM_PANEL_EDP

This bug happened on hybrid systems when both cpu_core and cpu_atom
have the same event name such as "UOPS_RETIRED.MS" while their event
terms are different, then during perf stat, the event for cpu_atom
will parse fail and then no output for cpu_atom.

UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/
UOPS_RETIRED.MS -> cpu_atom/period=0x1e8483,umask=0x1,event=0xc2/

It is because event terms in the "head" of parse_events_multi_pmu_add
will be changed to event terms for cpu_core after parsing UOPS_RETIRED.MS
for cpu_core, then when parsing the same event for cpu_atom, it still
uses the event terms for cpu_core, but event terms for cpu_atom are
different with cpu_core, the event parses for cpu_atom will fail. This
patch fixes it, the event terms should be parsed from the original
event.

This patch can work for the hybrid systems that have the same event
in more than 2 PMUs. It also can work in non-hybrid systems.

Before:

  # perf stat -v  -e  UOPS_RETIRED.MS  -a sleep 1

  Using CPUID GenuineIntel-6-97-1
  UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/
  Control descriptor is not initialized
  UOPS_RETIRED.MS: 2737845 16068518485 16068518485

 Performance counter stats for 'system wide':

         2,737,845      cpu_core/UOPS_RETIRED.MS/

       1.002553850 seconds time elapsed

After:

  # perf stat -v  -e  UOPS_RETIRED.MS  -a sleep 1

  Using CPUID GenuineIntel-6-97-1
  UOPS_RETIRED.MS -> cpu_core/period=0x1e8483,umask=0x4,event=0xc2,frontend=0x8/
  UOPS_RETIRED.MS -> cpu_atom/period=0x1e8483,umask=0x1,event=0xc2/
  Control descriptor is not initialized
  UOPS_RETIRED.MS: 1977555 16076950711 16076950711
  UOPS_RETIRED.MS: 568684 8038694234 8038694234

 Performance counter stats for 'system wide':

         1,977,555      cpu_core/UOPS_RETIRED.MS/
           568,684      cpu_atom/UOPS_RETIRED.MS/

       1.004758259 seconds time elapsed

Fixes: fb081153 ("perf parse-events: Allow config on kernel PMU events")
Reviewed-by: NKan Liang <kan.liang@linux.intel.com>
Signed-off-by: NZhengjun Xing <zhengjun.xing@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220307151627.30049-1-zhengjun.xing@linux.intel.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We did a NULL check after "epollfdp = calloc(...)", but we checked
"epollfd" instead of "epollfdp".
Signed-off-by: Weiguo Li <liwg06@foxmail.com>
Acked-by: NDavidlohr Bueso <dave@stgolabs.net>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/tencent_B5D64530EB9C7DBB8D2C88A0C790F1489D0A@qq.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

We did a null check after "tmp->symbol = strdup(...)", but we checked
"list->symbol" other than "tmp->symbol".
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: Weiguo Li <liwg06@foxmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/tencent_DF39269807EC9425E24787E6DB632441A405@qq.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To pick the changes from:

  d45476d9 ("x86/speculation: Rename RETPOLINE_AMD to RETPOLINE_LFENCE")

Its just a comment fixup.

This only causes these perf files to be rebuilt:

  CC       /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o
  CC       /tmp/build/perf/bench/mem-memset-x86-64-asm.o

And addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
  diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h

Cc: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/lkml/YiyiHatGaJQM7l/Y@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To pick the changes from:

  a5905d6a ("KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated")

That don't causes any changes in tooling (when built on x86), only
addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/kvm.h' differs from latest version at 'arch/arm64/include/uapi/asm/kvm.h'
  diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h

Cc: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/lkml/YiyhAK6sVPc83FaI@kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

As reported in [1], DRM_PANEL_EDP depends on DRM_DP_HELPER. Select
the option to fix the build failure. The error message is shown
below.

  arm-linux-gnueabihf-ld: drivers/gpu/drm/panel/panel-edp.o: in function
    `panel_edp_probe': panel-edp.c:(.text+0xb74): undefined reference to
    `drm_panel_dp_aux_backlight'
  make[1]: *** [/builds/linux/Makefile:1222: vmlinux] Error 1

The issue has been reported before, when DisplayPort helpers were
hidden behind the option CONFIG_DRM_KMS_HELPER. [2]

v2:
	* fix and expand commit description (Arnd)
Signed-off-by: NThomas Zimmermann <tzimmermann@suse.de>
Fixes: 9d6366e7 ("drm: fb_helper: improve CONFIG_FB dependency")
Reported-by: NNaresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: NLinux Kernel Functional Testing <lkft@linaro.org>
Reviewed-by: NLyude Paul <lyude@redhat.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/dri-devel/CA+G9fYvN0NyaVkRQmA1O6rX7H8PPaZrUAD7=RDy33QY9rUU-9g@mail.gmail.com/ # [1]
Link: https://lore.kernel.org/all/20211117062704.14671-1-rdunlap@infradead.org/ # [2]
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Lyude Paul <lyude@redhat.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20220203093922.20754-1-tzimmermann@suse.deSigned-off-by: NDave Airlie <airlied@redhat.com>

When CONFIG_GENERIC_CPU_VULNERABILITIES is not set, references
to spectre_v2_update_state() cause a build error, so provide an
empty stub for that function when the Kconfig option is not set.

Fixes this build error:

  arm-linux-gnueabi-ld: arch/arm/mm/proc-v7-bugs.o: in function `cpu_v7_bugs_init':
  proc-v7-bugs.c:(.text+0x52): undefined reference to `spectre_v2_update_state'
  arm-linux-gnueabi-ld: proc-v7-bugs.c:(.text+0x82): undefined reference to `spectre_v2_update_state'

Fixes: b9baf5c8 ("ARM: Spectre-BHB workaround")
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Reported-by: Nkernel test robot <lkp@intel.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: patches@armlinux.org.uk
Acked-by: NRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull RISC-V fixes from Palmer Dabbelt:

 - prevent users from enabling the alternatives framework (and thus
   errata handling) on XIP kernels, where runtime code patching does not
   function correctly.

 - properly detect offset overflow for AUIPC-based relocations in
   modules. This may manifest as modules calling arbitrary invalid
   addresses, depending on the address allocated when a module is
   loaded.

* tag 'riscv-for-linus-5.17-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Fix auipc+jalr relocation range checks
  riscv: alternative only works on !XIP_KERNEL

Pull powerpc fix from Michael Ellerman:
 "Fix STACKTRACE=n build, in particular for skiroot_defconfig"

* tag 'powerpc-5.17-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc: Fix STACKTRACE=n build

When building for Thumb2, the vectors make use of a local label. Sadly,
the Spectre BHB code also uses a local label with the same number which
results in the Thumb2 reference pointing at the wrong place. Fix this
by changing the number used for the Spectre BHB local label.

Fixes: b9baf5c8 ("ARM: Spectre-BHB workaround")
Tested-by: NNathan Chancellor <nathan@kernel.org>
Signed-off-by: NRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull MMC fixes from Ulf Hansson:
 "MMC core:
   - Restore (mostly) the busy polling for MMC_SEND_OP_COND

  MMC host:
   - meson-gx: Fix DMA usage of meson_mmc_post_req()"

* tag 'mmc-v5.17-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: core: Restore (almost) the busy polling for MMC_SEND_OP_COND
  mmc: meson: Fix usage of meson_mmc_post_req()

There is a limited amount of SGX memory (EPC) on each system.  When that
memory is used up, SGX has its own swapping mechanism which is similar
in concept but totally separate from the core mm/* code.  Instead of
swapping to disk, SGX swaps from EPC to normal RAM.  That normal RAM
comes from a shared memory pseudo-file and can itself be swapped by the
core mm code.  There is a hierarchy like this:

	EPC <-> shmem <-> disk

After data is swapped back in from shmem to EPC, the shmem backing
storage needs to be freed.  Currently, the backing shmem is not freed.
This effectively wastes the shmem while the enclave is running.  The
memory is recovered when the enclave is destroyed and the backing
storage freed.

Sort this out by freeing memory with shmem_truncate_range(), as soon as
a page is faulted back to the EPC.  In addition, free the memory for
PCMD pages as soon as all PCMD's in a page have been marked as unused
by zeroing its contents.

Cc: stable@vger.kernel.org
Fixes: 1728ab54 ("x86/sgx: Add a page reclaimer")
Reported-by: NDave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: NJarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220303223859.273187-1-jarkko@kernel.org

Merge misc fixes from David Howells:
 "A set of patches for watch_queue filter issues noted by Jann. I've
  added in a cleanup patch from Christophe Jaillet to convert to using
  formal bitmap specifiers for the note allocation bitmap.

  Also two filesystem fixes (afs and cachefiles)"

* emailed patches from David Howells <dhowells@redhat.com>:
  cachefiles: Fix volume coherency attribute
  afs: Fix potential thrashing in afs writeback
  watch_queue: Make comment about setting ->defunct more accurate
  watch_queue: Fix lack of barrier/sync/lock between post and read
  watch_queue: Free the alloc bitmap when the watch_queue is torn down
  watch_queue: Fix the alloc bitmap size to reflect notes allocated
  watch_queue: Use the bitmap API when applicable
  watch_queue: Fix to always request a pow-of-2 pipe ring size
  watch_queue: Fix to release page in ->release()
  watch_queue, pipe: Free watchqueue state after clearing pipe ring
  watch_queue: Fix filter limit check

A network filesystem may set coherency data on a volume cookie, and if
given, cachefiles will store this in an xattr on the directory in the
cache corresponding to the volume.

The function that sets the xattr just stores the contents of the volume
coherency buffer directly into the xattr, with nothing added; the
checking function, on the other hand, has a cut'n'paste error whereby it
tries to interpret the xattr contents as would be the xattr on an
ordinary file (using the cachefiles_xattr struct).  This results in a
failure to match the coherency data because the buffer ends up being
shifted by 18 bytes.

Fix this by defining a structure specifically for the volume xattr and
making both the setting and checking functions use it.

Since the volume coherency doesn't work if used, take the opportunity to
insert a reserved field for future use, set it to 0 and check that it is
0.  Log mismatch through the appropriate tracepoint.

Note that this only affects cifs; 9p, afs, ceph and nfs don't use the
volume coherency data at the moment.

Fixes: 32e15003 ("fscache, cachefiles: Store the volume coherency data")
Reported-by: NRohith Surabattula <rohiths.msft@gmail.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reviewed-by: NJeff Layton <jlayton@kernel.org>
cc: Steve French <smfrench@gmail.com>
cc: linux-cifs@vger.kernel.org
cc: linux-cachefs@redhat.com
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In afs_writepages_region(), if the dirty page we find is undergoing
writeback or write to cache, but the sync_mode is WB_SYNC_NONE, we go
round the loop trying the same page again and again with no pausing or
waiting unless and until another thread manages to clear the writeback
and fscache flags.

Fix this with three measures:

 (1) Advance start to after the page we found.

 (2) Break out of the loop and return if rescheduling is requested.

 (3) Arbitrarily give up after a maximum of 5 skips.

Fixes: 31143d5d ("AFS: implement basic file write support")
Reported-by: NMarc Dionne <marc.dionne@auristor.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Tested-by: NMarc Dionne <marc.dionne@auristor.com>
Acked-by: NMarc Dionne <marc.dionne@auristor.com>
Link: https://lore.kernel.org/r/164692725757.2097000.2060513769492301854.stgit@warthog.procyon.org.uk/ # v1
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since kprobe_int3_handler() is called in do_int3(), probing do_int3()
can cause a breakpoint recursion and crash the kernel. Therefore,
do_int3() should be marked as NOKPROBE_SYMBOL.

Fixes: 21e28290 ("x86/traps: Split int3 handler up")
Signed-off-by: NLi Huafei <lihuafei1@huawei.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Acked-by: NMasami Hiramatsu <mhiramat@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220310120915.63349-1-lihuafei1@huawei.com

watch_queue_clear() has a comment stating that setting ->defunct to true
preventing new additions as well as preventing notifications.  Whilst
the latter is true, the first bit is superfluous since at the time this
function is called, the pipe cannot be accessed to add new event
sources.

Remove the "new additions" bit from the comment.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's nothing to synchronise post_one_notification() versus
pipe_read().  Whilst posting is done under pipe->rd_wait.lock, the
reader only takes pipe->mutex which cannot bar notification posting as
that may need to be made from contexts that cannot sleep.

Fix this by setting pipe->head with a barrier in post_one_notification()
and reading pipe->head with a barrier in pipe_read().

If that's not sufficient, the rd_wait.lock will need to be taken,
possibly in a ->confirm() op so that it only applies to notifications.
The lock would, however, have to be dropped before copy_page_to_iter()
is invoked.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Free the watch_queue note allocation bitmap when the watch_queue is
destroyed.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, watch_queue_set_size() sets the number of notes available in
wqueue->nr_notes according to the number of notes allocated, but sets
the size of the bitmap to the unrounded number of notes originally asked
for.

Fix this by setting the bitmap size to the number of notes we're
actually going to make available (ie. the number allocated).

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use bitmap_alloc() to simplify code, improve the semantic and reduce
some open-coded arithmetic in allocator arguments.

Also change a memset(0xff) into an equivalent bitmap_fill() to keep
consistency.
Signed-off-by: NChristophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The pipe ring size must always be a power of 2 as the head and tail
pointers are masked off by AND'ing with the size of the ring - 1.
watch_queue_set_size(), however, lets you specify any number of notes
between 1 and 511.  This number is passed through to pipe_resize_ring()
without checking/forcing its alignment.

Fix this by rounding the number of slots required up to the nearest
power of two.  The request is meant to guarantee that at least that many
notifications can be generated before the queue is full, so rounding
down isn't an option, but, alternatively, it may be better to give an
error if we aren't allowed to allocate that much ring space.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a pipe ring descriptor points to a notification message, the
refcount on the backing page is incremented by the generic get function,
but the release function, which marks the bitmap, doesn't drop the page
ref.

Fix this by calling generic_pipe_buf_release() at the end of
watch_queue_pipe_buf_release().

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In free_pipe_info(), free the watchqueue state after clearing the pipe
ring as each pipe ring descriptor has a release function, and in the
case of a notification message, this is watch_queue_pipe_buf_release()
which tries to mark the allocation bitmap that was previously released.

Fix this by moving the put of the pipe's ref on the watch queue to after
the ring has been cleared.  We still need to call watch_queue_clear()
before doing that to make sure that the pipe is disconnected from any
notification sources first.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In watch_queue_set_filter(), there are a couple of places where we check
that the filter type value does not exceed what the type_filter bitmap
can hold.  One place calculates the number of bits by:

   if (tf[i].type >= sizeof(wfilter->type_filter) * 8)

which is fine, but the second does:

   if (tf[i].type >= sizeof(wfilter->type_filter) * BITS_PER_LONG)

which is not.  This can lead to a couple of out-of-bounds writes due to
a too-large type:

 (1) __set_bit() on wfilter->type_filter
 (2) Writing more elements in wfilter->filters[] than we allocated.

Fix this by just using the proper WATCH_TYPE__NR instead, which is the
number of types we actually know about.

The bug may cause an oops looking something like:

  BUG: KASAN: slab-out-of-bounds in watch_queue_set_filter+0x659/0x740
  Write of size 4 at addr ffff88800d2c66bc by task watch_queue_oob/611
  ...
  Call Trace:
   <TASK>
   dump_stack_lvl+0x45/0x59
   print_address_description.constprop.0+0x1f/0x150
   ...
   kasan_report.cold+0x7f/0x11b
   ...
   watch_queue_set_filter+0x659/0x740
   ...
   __x64_sys_ioctl+0x127/0x190
   do_syscall_64+0x43/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xae

  Allocated by task 611:
   kasan_save_stack+0x1e/0x40
   __kasan_kmalloc+0x81/0xa0
   watch_queue_set_filter+0x23a/0x740
   __x64_sys_ioctl+0x127/0x190
   do_syscall_64+0x43/0x90
   entry_SYSCALL_64_after_hwframe+0x44/0xae

  The buggy address belongs to the object at ffff88800d2c66a0
   which belongs to the cache kmalloc-32 of size 32
  The buggy address is located 28 bytes inside of
   32-byte region [ffff88800d2c66a0, ffff88800d2c66c0)

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull drm fixes from Dave Airlie:
 "As expected at this stage its pretty quiet, one sun4i mixer fix and
  one i915 display flicker fix:

  i915:
   - fix psr screen flicker

  sun4i:
   - mixer format fix"

* tag 'drm-fixes-2022-03-11' of git://anongit.freedesktop.org/drm/drm:
  drm/sun4i: mixer: Fix P010 and P210 format numbers
  drm/i915/psr: Set "SF Partial Frame Enable" also on full update

RISC-V can do PC-relative jumps with a 32bit range using the following
two instructions:

	auipc	t0, imm20	; t0 = PC + imm20 * 2^12
	jalr	ra, t0, imm12	; ra = PC + 4, PC = t0 + imm12

Crucially both the 20bit immediate imm20 and the 12bit immediate imm12
are treated as two's-complement signed values. For this reason the
immediates are usually calculated like this:

	imm20 = (offset + 0x800) >> 12
	imm12 = offset & 0xfff

..where offset is the signed offset from the auipc instruction. When
the 11th bit of offset is 0 the addition of 0x800 doesn't change the top
20 bits and imm12 considered positive. When the 11th bit is 1 the carry
of the addition by 0x800 means imm20 is one higher, but since imm12 is
then considered negative the two's complement representation means it
all cancels out nicely.

However, this addition by 0x800 (2^11) means an offset greater than or
equal to 2^31 - 2^11 would overflow so imm20 is considered negative and
result in a backwards jump. Similarly the lower range of offset is also
moved down by 2^11 and hence the true 32bit range is

	[-2^31 - 2^11, 2^31 - 2^11)
Signed-off-by: NEmil Renner Berthing <kernel@esmil.dk>
Fixes: e2c0cdfb ("RISC-V: User-facing API")
Cc: stable@vger.kernel.org
Signed-off-by: NPalmer Dabbelt <palmer@rivosinc.com>

Merge tag 'drm-intel-fixes-2022-03-10' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

- Fix PSR2 when selective fetch is enabled and cursor at (-1, -1) (Jouni Högander)
Signed-off-by: NDave Airlie <airlied@redhat.com>
From: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/YinTFSFg++HvuFpZ@tursulin-mobl2