Merge tag 'v6.6.6' into dev-6.6

This is the 6.6.6 stable release

Signed-off-by: Joel Stanley <joel@jms.id.au>

RISC-V: hwprobe: Fix vDSO SIGSEGV

[ Upstream commit e1c05b3bf80f829ced464bdca90f1dfa96e8d251 ]

A hwprobe pair key is signed, but the hwprobe vDSO function was
only checking that the upper bound was

RISC-V: hwprobe: Fix vDSO SIGSEGV

[ Upstream commit e1c05b3bf80f829ced464bdca90f1dfa96e8d251 ]

A hwprobe pair key is signed, but the hwprobe vDSO function was
only checking that the upper bound was valid. In order to help
avoid this type of problem in the future, and in anticipation of
this check becoming more complicated with sparse keys, introduce
and use a "key is valid" predicate function for the check.

Fixes: aa5af0aa90ba ("RISC-V: Add hwprobe vDSO function and data")
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20231010165101.14942-2-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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Merge branch 'next' into for-linus

Prepare input updates for 6.6 merge window.

Merge tag 'v6.4' into next

Sync up with mainline to bring in updates to shared infrastructure.

Merge branch 'for-6.5/apple' into for-linus

- improved support for Keychron K8 keyboard (Lasse Brun)

Merge drm/drm-next into drm-misc-next-fixes

Backmerging to sync drm-misc-next-fixes with drm-misc-next.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patche

Merge branch 'drm-next' of git://anongit.freedesktop.org/drm/drm into msm-next-lumag-base

Merge the drm-next tree to pick up the DRM DSC helpers (merged via
drm-intel-next tree). MSM DSC v1.2 patches depend on these helpers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

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Merge tag 'v6.4-rc4' into wpan-next/staging

Linux 6.4-rc4

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko

Merge drm/drm-next into drm-intel-gt-next

For conflict avoidance we need the following commit:

c9a9f18d3ad8 drm/i915/huc: use const struct bus_type pointers

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>

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Merge drm/drm-next into drm-intel-next

Backmerge to get some hwmon dependencies.

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

Merge drm/drm-fixes into drm-misc-fixes

Let's bring 6.4-rc1 in drm-misc-fixes to start the new fix cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge drm/drm-next into drm-misc-next

Start the 6.5 release cycle.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>

Merge tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

- Support for runtime detection of the Svnapot extension

Merge tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

- Support for runtime detection of the Svnapot extension

- Support for Zicboz when clearing pages

- We've moved to GENERIC_ENTRY

- Support for !MMU on rv32 systems

- The linear region is now mapped via huge pages

- Support for building relocatable kernels

- Support for the hwprobe interface

- Various fixes and cleanups throughout the tree

* tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits)
RISC-V: hwprobe: Explicity check for -1 in vdso init
RISC-V: hwprobe: There can only be one first
riscv: Allow to downgrade paging mode from the command line
dt-bindings: riscv: add sv57 mmu-type
RISC-V: hwprobe: Remove __init on probe_vendor_features()
riscv: Use --emit-relocs in order to move .rela.dyn in init
riscv: Check relocations at compile time
powerpc: Move script to check relocations at compile time in scripts/
riscv: Introduce CONFIG_RELOCATABLE
riscv: Move .rela.dyn outside of init to avoid empty relocations
riscv: Prepare EFI header for relocatable kernels
riscv: Unconditionnally select KASAN_VMALLOC if KASAN
riscv: Fix ptdump when KASAN is enabled
riscv: Fix EFI stub usage of KASAN instrumented strcmp function
riscv: Move DTB_EARLY_BASE_VA to the kernel address space
riscv: Rework kasan population functions
riscv: Split early and final KASAN population functions
riscv: Use PUD/P4D/PGD pages for the linear mapping
riscv: Move the linear mapping creation in its own function
riscv: Get rid of riscv_pfn_base variable
...

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Merge patch series "RISC-V Hardware Probing User Interface"

Evan Green <evan@rivosinc.com> says:

There's been a bunch of off-list discussions about this, including at
Plumbers. The original plan w

Merge patch series "RISC-V Hardware Probing User Interface"

Evan Green <evan@rivosinc.com> says:

There's been a bunch of off-list discussions about this, including at
Plumbers. The original plan was to do something involving providing an
ISA string to userspace, but ISA strings just aren't sufficient for a
stable ABI any more: in order to parse an ISA string users need the
version of the specifications that the string is written to, the version
of each extension (sometimes at a finer granularity than the RISC-V
releases/versions encode), and the expected use case for the ISA string
(ie, is it a U-mode or M-mode string). That's a lot of complexity to
try and keep ABI compatible and it's probably going to continue to grow,
as even if there's no more complexity in the specifications we'll have
to deal with the various ISA string parsing oddities that end up all
over userspace.

Instead this patch set takes a very different approach and provides a set
of key/value pairs that encode various bits about the system. The big
advantage here is that we can clearly define what these mean so we can
ensure ABI stability, but it also allows us to encode information that's
unlikely to ever appear in an ISA string (see the misaligned access
performance, for example). The resulting interface looks a lot like
what arm64 and x86 do, and will hopefully fit well into something like
ACPI in the future.

The actual user interface is a syscall, with a vDSO function in front of
it. The vDSO function can answer some queries without a syscall at all,
and falls back to the syscall for cases it doesn't have answers to.
Currently we prepopulate it with an array of answers for all keys and
a CPU set of "all CPUs". This can be adjusted as necessary to provide
fast answers to the most common queries.

An example series in glibc exposing this syscall and using it in an
ifunc selector for memcpy can be found at [1].

I was asked about the performance delta between this and something like
sysfs. I created a small test program and ran it on a Nezha D1
Allwinner board. Doing each operation 100000 times and dividing, these
operations take the following amount of time:
- open()+read()+close() of /sys/kernel/cpu_byteorder: 3.8us
- access("/sys/kernel/cpu_byteorder", R_OK): 1.3us
- riscv_hwprobe() vDSO and syscall: .0094us
- riscv_hwprobe() vDSO with no syscall: 0.0091us

These numbers get farther apart if we query multiple keys, as sysfs will
scale linearly with the number of keys, where the dedicated syscall
stays the same. To frame these numbers, I also did a tight
fork/exec/wait loop, which I measured as 4.8ms. So doing 4
open/read/close operations is a delta of about 0.3%, versus a single vDSO
call is a delta of essentially zero.

[1] https://patchwork.ozlabs.org/project/glibc/list/?series=343050

* b4-shazam-merge:
RISC-V: Add hwprobe vDSO function and data
selftests: Test the new RISC-V hwprobe interface
RISC-V: hwprobe: Support probing of misaligned access performance
RISC-V: hwprobe: Add support for RISCV_HWPROBE_BASE_BEHAVIOR_IMA
RISC-V: Add a syscall for HW probing
RISC-V: Move struct riscv_cpuinfo to new header

Link: https://lore.kernel.org/r/20230407231103.2622178-1-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

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RISC-V: Add hwprobe vDSO function and data

Add a vDSO function __vdso_riscv_hwprobe, which can sit in front of the
riscv_hwprobe syscall and answer common queries. We stash a copy of
static answers

RISC-V: Add hwprobe vDSO function and data

Add a vDSO function __vdso_riscv_hwprobe, which can sit in front of the
riscv_hwprobe syscall and answer common queries. We stash a copy of
static answers for the "all CPUs" case in the vDSO data page. This data
is private to the vDSO, so we can decide later to change what's stored
there or under what conditions we defer to the syscall. Currently all
data can be discovered at boot, so the vDSO function answers all queries
when the cpumask is set to the "all CPUs" hint.

There's also a boolean in the data that lets the vDSO function know that
all CPUs are the same. In that case, the vDSO will also answer queries
for arbitrary CPU masks in addition to the "all CPUs" hint.

Signed-off-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-7-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

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