Commit graph

656 commits

Author SHA1 Message Date
Mark Brown
d12aada8df arm64/hwcap: Add support for SVE 2.1
FEAT_SVE2p1 introduces a number of new SVE instructions. Since there is no
new architectural state added kernel support is simply a new hwcap which
lets userspace know that the feature is supported.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-6-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-09 17:54:53 +00:00
Mark Brown
939e4649d4 arm64/hwcap: Add support for FEAT_RPRFM
FEAT_RPRFM adds a new range prefetch hint within the existing PRFM space
for range prefetch hinting. Add a new hwcap to allow userspace to discover
support for the new instruction.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-09 17:54:53 +00:00
Mark Brown
95aa6860d6 arm64/hwcap: Add support for FEAT_CSSC
FEAT_CSSC adds a number of new instructions usable to optimise common short
sequences of instructions, add a hwcap indicating that the feature is
available and can be used by userspace.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-09 17:54:53 +00:00
Ard Biesheuvel
01ab991fc0 arm64: Enable data independent timing (DIT) in the kernel
The ARM architecture revision v8.4 introduces a data independent timing
control (DIT) which can be set at any exception level, and instructs the
CPU to avoid optimizations that may result in a correlation between the
execution time of certain instructions and the value of the data they
operate on.

The DIT bit is part of PSTATE, and is therefore context switched as
usual, given that it becomes part of the saved program state (SPSR) when
taking an exception. We have also defined a hwcap for DIT, and so user
space can discover already whether or nor DIT is available. This means
that, as far as user space is concerned, DIT is wired up and fully
functional.

In the kernel, however, we never bothered with DIT: we disable at it
boot (i.e., INIT_PSTATE_EL1 has DIT cleared) and ignore the fact that we
might run with DIT enabled if user space happened to set it.

Currently, we have no idea whether or not running privileged code with
DIT disabled on a CPU that implements support for it may result in a
side channel that exposes privileged data to unprivileged user space
processes, so let's be cautious and just enable DIT while running in the
kernel if supported by all CPUs.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Adam Langley <agl@google.com>
Link: https://lore.kernel.org/all/YwgCrqutxmX0W72r@gmail.com/
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20221107172400.1851434-1-ardb@kernel.org
[will: Removed cpu_has_dit() as per Mark's suggestion on the list]
Signed-off-by: Will Deacon <will@kernel.org>
2022-11-08 14:55:10 +00:00
Amit Daniel Kachhap
85f1506337 arm64: cpufeature: Fix the visibility of compat hwcaps
Commit 237405ebef ("arm64: cpufeature: Force HWCAP to be based on the
sysreg visible to user-space") forced the hwcaps to use sanitised
user-space view of the id registers. However, the ID register structures
used to select few compat cpufeatures (vfp, crc32, ...) are masked and
hence such hwcaps do not appear in /proc/cpuinfo anymore for PER_LINUX32
personality.

Add the ID register structures explicitly and set the relevant entry as
visible. As these ID registers are now of type visible so make them
available in 64-bit userspace by making necessary changes in register
emulation logic and documentation.

While at it, update the comment for structure ftr_generic_32bits[] which
lists the ID register that use it.

Fixes: 237405ebef ("arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space")
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20221103082232.19189-1-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-11-03 18:04:56 +00:00
Linus Torvalds
18fd049731 arm64 updates for 6.1:
- arm64 perf: DDR PMU driver for Alibaba's T-Head Yitian 710 SoC, SVE
   vector granule register added to the user regs together with SVE perf
   extensions documentation.
 
 - SVE updates: add HWCAP for SVE EBF16, update the SVE ABI documentation
   to match the actual kernel behaviour (zeroing the registers on syscall
   rather than "zeroed or preserved" previously).
 
 - More conversions to automatic system registers generation.
 
 - vDSO: use self-synchronising virtual counter access in gettimeofday()
   if the architecture supports it.
 
 - arm64 stacktrace cleanups and improvements.
 
 - arm64 atomics improvements: always inline assembly, remove LL/SC
   trampolines.
 
 - Improve the reporting of EL1 exceptions: rework BTI and FPAC exception
   handling, better EL1 undefs reporting.
 
 - Cortex-A510 erratum 2658417: remove BF16 support due to incorrect
   result.
 
 - arm64 defconfig updates: build CoreSight as a module, enable options
   necessary for docker, memory hotplug/hotremove, enable all PMUs
   provided by Arm.
 
 - arm64 ptrace() support for TPIDR2_EL0 (register provided with the SME
   extensions).
 
 - arm64 ftraces updates/fixes: fix module PLTs with mcount, remove
   unused function.
 
 - kselftest updates for arm64: simple HWCAP validation, FP stress test
   improvements, validation of ZA regs in signal handlers, include larger
   SVE and SME vector lengths in signal tests, various cleanups.
 
 - arm64 alternatives (code patching) improvements to robustness and
   consistency: replace cpucap static branches with equivalent
   alternatives, associate callback alternatives with a cpucap.
 
 - Miscellaneous updates: optimise kprobe performance of patching
   single-step slots, simplify uaccess_mask_ptr(), move MTE registers
   initialisation to C, support huge vmalloc() mappings, run softirqs on
   the per-CPU IRQ stack, compat (arm32) misalignment fixups for
   multiword accesses.
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - arm64 perf: DDR PMU driver for Alibaba's T-Head Yitian 710 SoC, SVE
   vector granule register added to the user regs together with SVE perf
   extensions documentation.

 - SVE updates: add HWCAP for SVE EBF16, update the SVE ABI
   documentation to match the actual kernel behaviour (zeroing the
   registers on syscall rather than "zeroed or preserved" previously).

 - More conversions to automatic system registers generation.

 - vDSO: use self-synchronising virtual counter access in gettimeofday()
   if the architecture supports it.

 - arm64 stacktrace cleanups and improvements.

 - arm64 atomics improvements: always inline assembly, remove LL/SC
   trampolines.

 - Improve the reporting of EL1 exceptions: rework BTI and FPAC
   exception handling, better EL1 undefs reporting.

 - Cortex-A510 erratum 2658417: remove BF16 support due to incorrect
   result.

 - arm64 defconfig updates: build CoreSight as a module, enable options
   necessary for docker, memory hotplug/hotremove, enable all PMUs
   provided by Arm.

 - arm64 ptrace() support for TPIDR2_EL0 (register provided with the SME
   extensions).

 - arm64 ftraces updates/fixes: fix module PLTs with mcount, remove
   unused function.

 - kselftest updates for arm64: simple HWCAP validation, FP stress test
   improvements, validation of ZA regs in signal handlers, include
   larger SVE and SME vector lengths in signal tests, various cleanups.

 - arm64 alternatives (code patching) improvements to robustness and
   consistency: replace cpucap static branches with equivalent
   alternatives, associate callback alternatives with a cpucap.

 - Miscellaneous updates: optimise kprobe performance of patching
   single-step slots, simplify uaccess_mask_ptr(), move MTE registers
   initialisation to C, support huge vmalloc() mappings, run softirqs on
   the per-CPU IRQ stack, compat (arm32) misalignment fixups for
   multiword accesses.

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (126 commits)
  arm64: alternatives: Use vdso/bits.h instead of linux/bits.h
  arm64/kprobe: Optimize the performance of patching single-step slot
  arm64: defconfig: Add Coresight as module
  kselftest/arm64: Handle EINTR while reading data from children
  kselftest/arm64: Flag fp-stress as exiting when we begin finishing up
  kselftest/arm64: Don't repeat termination handler for fp-stress
  ARM64: reloc_test: add __init/__exit annotations to module init/exit funcs
  arm64/mm: fold check for KFENCE into can_set_direct_map()
  arm64: ftrace: fix module PLTs with mcount
  arm64: module: Remove unused plt_entry_is_initialized()
  arm64: module: Make plt_equals_entry() static
  arm64: fix the build with binutils 2.27
  kselftest/arm64: Don't enable v8.5 for MTE selftest builds
  arm64: uaccess: simplify uaccess_mask_ptr()
  arm64: asm/perf_regs.h: Avoid C++-style comment in UAPI header
  kselftest/arm64: Fix typo in hwcap check
  arm64: mte: move register initialization to C
  arm64: mm: handle ARM64_KERNEL_USES_PMD_MAPS in vmemmap_populate()
  arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()
  arm64/sve: Add Perf extensions documentation
  ...
2022-10-06 11:51:49 -07:00
Catalin Marinas
53630a1f61 Merge branch 'for-next/misc' into for-next/core
* for-next/misc:
  : Miscellaneous patches
  arm64/kprobe: Optimize the performance of patching single-step slot
  ARM64: reloc_test: add __init/__exit annotations to module init/exit funcs
  arm64/mm: fold check for KFENCE into can_set_direct_map()
  arm64: uaccess: simplify uaccess_mask_ptr()
  arm64: mte: move register initialization to C
  arm64: mm: handle ARM64_KERNEL_USES_PMD_MAPS in vmemmap_populate()
  arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()
  arm64: support huge vmalloc mappings
  arm64: spectre: increase parameters that can be used to turn off bhb mitigation individually
  arm64: run softirqs on the per-CPU IRQ stack
  arm64: compat: Implement misalignment fixups for multiword loads
2022-09-30 09:18:26 +01:00
Catalin Marinas
c704cf27a1 Merge branch 'for-next/alternatives' into for-next/core
* for-next/alternatives:
  : Alternatives (code patching) improvements
  arm64: fix the build with binutils 2.27
  arm64: avoid BUILD_BUG_ON() in alternative-macros
  arm64: alternatives: add shared NOP callback
  arm64: alternatives: add alternative_has_feature_*()
  arm64: alternatives: have callbacks take a cap
  arm64: alternatives: make alt_region const
  arm64: alternatives: hoist print out of __apply_alternatives()
  arm64: alternatives: proton-pack: prepare for cap changes
  arm64: alternatives: kvm: prepare for cap changes
  arm64: cpufeature: make cpus_have_cap() noinstr-safe
2022-09-30 09:18:22 +01:00
Catalin Marinas
b23ec74cbd Merge branches 'for-next/doc', 'for-next/sve', 'for-next/sysreg', 'for-next/gettimeofday', 'for-next/stacktrace', 'for-next/atomics', 'for-next/el1-exceptions', 'for-next/a510-erratum-2658417', 'for-next/defconfig', 'for-next/tpidr2_el0' and 'for-next/ftrace', remote-tracking branch 'arm64/for-next/perf' into for-next/core
* arm64/for-next/perf:
  arm64: asm/perf_regs.h: Avoid C++-style comment in UAPI header
  arm64/sve: Add Perf extensions documentation
  perf: arm64: Add SVE vector granule register to user regs
  MAINTAINERS: add maintainers for Alibaba' T-Head PMU driver
  drivers/perf: add DDR Sub-System Driveway PMU driver for Yitian 710 SoC
  docs: perf: Add description for Alibaba's T-Head PMU driver

* for-next/doc:
  : Documentation/arm64 updates
  arm64/sve: Document our actual ABI for clearing registers on syscall

* for-next/sve:
  : SVE updates
  arm64/sysreg: Add hwcap for SVE EBF16

* for-next/sysreg: (35 commits)
  : arm64 system registers generation (more conversions)
  arm64/sysreg: Fix a few missed conversions
  arm64/sysreg: Convert ID_AA64AFRn_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64DFR1_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64FDR0_EL1 to automatic generation
  arm64/sysreg: Use feature numbering for PMU and SPE revisions
  arm64/sysreg: Add _EL1 into ID_AA64DFR0_EL1 definition names
  arm64/sysreg: Align field names in ID_AA64DFR0_EL1 with architecture
  arm64/sysreg: Add defintion for ALLINT
  arm64/sysreg: Convert SCXTNUM_EL1 to automatic generation
  arm64/sysreg: Convert TIPDR_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64PFR1_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64PFR0_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64MMFR2_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64MMFR1_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64MMFR0_EL1 to automatic generation
  arm64/sysreg: Convert HCRX_EL2 to automatic generation
  arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 SME enumeration
  arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 BTI enumeration
  arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 fractional version fields
  arm64/sysreg: Standardise naming for MTE feature enumeration
  ...

* for-next/gettimeofday:
  : Use self-synchronising counter access in gettimeofday() (if FEAT_ECV)
  arm64: vdso: use SYS_CNTVCTSS_EL0 for gettimeofday
  arm64: alternative: patch alternatives in the vDSO
  arm64: module: move find_section to header

* for-next/stacktrace:
  : arm64 stacktrace cleanups and improvements
  arm64: stacktrace: track hyp stacks in unwinder's address space
  arm64: stacktrace: track all stack boundaries explicitly
  arm64: stacktrace: remove stack type from fp translator
  arm64: stacktrace: rework stack boundary discovery
  arm64: stacktrace: add stackinfo_on_stack() helper
  arm64: stacktrace: move SDEI stack helpers to stacktrace code
  arm64: stacktrace: rename unwind_next_common() -> unwind_next_frame_record()
  arm64: stacktrace: simplify unwind_next_common()
  arm64: stacktrace: fix kerneldoc comments

* for-next/atomics:
  : arm64 atomics improvements
  arm64: atomic: always inline the assembly
  arm64: atomics: remove LL/SC trampolines

* for-next/el1-exceptions:
  : Improve the reporting of EL1 exceptions
  arm64: rework BTI exception handling
  arm64: rework FPAC exception handling
  arm64: consistently pass ESR_ELx to die()
  arm64: die(): pass 'err' as long
  arm64: report EL1 UNDEFs better

* for-next/a510-erratum-2658417:
  : Cortex-A510: 2658417: remove BF16 support due to incorrect result
  arm64: errata: remove BF16 HWCAP due to incorrect result on Cortex-A510
  arm64: cpufeature: Expose get_arm64_ftr_reg() outside cpufeature.c
  arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space

* for-next/defconfig:
  : arm64 defconfig updates
  arm64: defconfig: Add Coresight as module
  arm64: Enable docker support in defconfig
  arm64: defconfig: Enable memory hotplug and hotremove config
  arm64: configs: Enable all PMUs provided by Arm

* for-next/tpidr2_el0:
  : arm64 ptrace() support for TPIDR2_EL0
  kselftest/arm64: Add coverage of TPIDR2_EL0 ptrace interface
  arm64/ptrace: Support access to TPIDR2_EL0
  arm64/ptrace: Document extension of NT_ARM_TLS to cover TPIDR2_EL0
  kselftest/arm64: Add test coverage for NT_ARM_TLS

* for-next/ftrace:
  : arm64 ftraces updates/fixes
  arm64: ftrace: fix module PLTs with mcount
  arm64: module: Remove unused plt_entry_is_initialized()
  arm64: module: Make plt_equals_entry() static
2022-09-30 09:17:57 +01:00
Sami Tolvanen
607289a7cd treewide: Drop function_nocfi
With -fsanitize=kcfi, we no longer need function_nocfi() as
the compiler won't change function references to point to a
jump table. Remove all implementations and uses of the macro.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220908215504.3686827-14-samitolvanen@google.com
2022-09-26 10:13:14 -07:00
Sami Tolvanen
5f20997c19 arm64: Drop unneeded __nocfi attributes
With -fsanitize=kcfi, CONFIG_CFI_CLANG no longer has issues
with address space confusion in functions that switch to linear
mapping. Now that the indirectly called assembly functions have
type annotations, drop the __nocfi attributes.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220908215504.3686827-12-samitolvanen@google.com
2022-09-26 10:13:14 -07:00
Peter Collingbourne
973b9e3733 arm64: mte: move register initialization to C
If FEAT_MTE2 is disabled via the arm64.nomte command line argument on a
CPU that claims to support FEAT_MTE2, the kernel will use Tagged Normal
in the MAIR. If we interpret arm64.nomte to mean that the CPU does not
in fact implement FEAT_MTE2, setting the system register like this may
lead to UNSPECIFIED behavior. Fix it by arranging for MAIR to be set
in the C function cpu_enable_mte which is called based on the sanitized
version of the system register.

There is no need for the rest of the MTE-related system register
initialization to happen from assembly, with the exception of TCR_EL1,
which must be set to include at least TBI1 because the secondary CPUs
access KASan-allocated data structures early. Therefore, make the TCR_EL1
initialization unconditional and move the rest of the initialization to
cpu_enable_mte so that we no longer have a dependency on the unsanitized
ID register value.

Co-developed-by: Evgenii Stepanov <eugenis@google.com>
Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Evgenii Stepanov <eugenis@google.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 3b714d24ef ("arm64: mte: CPU feature detection and initial sysreg configuration")
Cc: <stable@vger.kernel.org> # 5.10.x
Link: https://lore.kernel.org/r/20220915222053.3484231-1-eugenis@google.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-22 18:02:50 +01:00
Mark Rutland
21fb26bfb0 arm64: alternatives: add alternative_has_feature_*()
Currrently we use a mixture of alternative sequences and static branches
to handle features detected at boot time. For ease of maintenance we
generally prefer to use static branches in C code, but this has a few
downsides:

* Each static branch has metadata in the __jump_table section, which is
  not discarded after features are finalized. This wastes some space,
  and slows down the patching of other static branches.

* The static branches are patched at a different point in time from the
  alternatives, so changes are not atomic. This leaves a transient
  period where there could be a mismatch between the behaviour of
  alternatives and static branches, which could be problematic for some
  features (e.g. pseudo-NMI).

* More (instrumentable) kernel code is executed to patch each static
  branch, which can be risky when patching certain features (e.g.
  irqflags management for pseudo-NMI).

* When CONFIG_JUMP_LABEL=n, static branches are turned into a load of a
  flag and a conditional branch. This means it isn't safe to use such
  static branches in an alternative address space (e.g. the NVHE/PKVM
  hyp code), where the generated address isn't safe to acccess.

To deal with these issues, this patch introduces new
alternative_has_feature_*() helpers, which work like static branches but
are patched using alternatives. This ensures the patching is performed
at the same time as other alternative patching, allows the metadata to
be freed after patching, and is safe for use in alternative address
spaces.

Note that all supported toolchains have asm goto support, and since
commit:

  a0a12c3ed0 ("asm goto: eradicate CC_HAS_ASM_GOTO)"

... the CC_HAS_ASM_GOTO Kconfig symbol has been removed, so no feature
check is necessary, and we can always make use of asm goto.

Additionally, note that:

* This has no impact on cpus_have_cap(), which is a dynamic check.

* This has no functional impact on cpus_have_const_cap(). The branches
  are patched slightly later than before this patch, but these branches
  are not reachable until caps have been finalised.

* It is now invalid to use cpus_have_final_cap() in the window between
  feature detection and patching. All existing uses are only expected
  after patching anyway, so this should not be a problem.

* The LSE atomics will now be enabled during alternatives patching
  rather than immediately before. As the LL/SC an LSE atomics are
  functionally equivalent this should not be problematic.

When building defconfig with GCC 12.1.0, the resulting Image is 64KiB
smaller:

| % ls -al Image-*
| -rw-r--r-- 1 mark mark 37108224 Aug 23 09:56 Image-after
| -rw-r--r-- 1 mark mark 37173760 Aug 23 09:54 Image-before

According to bloat-o-meter.pl:

| add/remove: 44/34 grow/shrink: 602/1294 up/down: 39692/-61108 (-21416)
| Function                                     old     new   delta
| [...]
| Total: Before=16618336, After=16596920, chg -0.13%
| add/remove: 0/2 grow/shrink: 0/0 up/down: 0/-1296 (-1296)
| Data                                         old     new   delta
| arm64_const_caps_ready                        16       -     -16
| cpu_hwcap_keys                              1280       -   -1280
| Total: Before=8987120, After=8985824, chg -0.01%
| add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0)
| RO Data                                      old     new   delta
| Total: Before=18408, After=18408, chg +0.00%

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220912162210.3626215-8-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 17:15:03 +01:00
Mark Rutland
4c0bd995d7 arm64: alternatives: have callbacks take a cap
Today, callback alternatives are special-cased within
__apply_alternatives(), and are applied alongside patching for system
capabilities as ARM64_NCAPS is not part of the boot_capabilities feature
mask.

This special-casing is less than ideal. Giving special meaning to
ARM64_NCAPS for this requires some structures and loops to use
ARM64_NCAPS + 1 (AKA ARM64_NPATCHABLE), while others use ARM64_NCAPS.
It's also not immediately clear callback alternatives are only applied
when applying alternatives for system-wide features.

To make this a bit clearer, changes the way that callback alternatives
are identified to remove the special-casing of ARM64_NCAPS, and to allow
callback alternatives to be associated with a cpucap as with all other
alternatives.

New cpucaps, ARM64_ALWAYS_BOOT and ARM64_ALWAYS_SYSTEM are added which
are always detected alongside boot cpu capabilities and system
capabilities respectively. All existing callback alternatives are made
to use ARM64_ALWAYS_SYSTEM, and so will be patched at the same point
during the boot flow as before.

Subsequent patches will make more use of these new cpucaps.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Joey Gouly <joey.gouly@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220912162210.3626215-7-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 17:15:03 +01:00
James Morse
445c953e4a arm64: cpufeature: Expose get_arm64_ftr_reg() outside cpufeature.c
get_arm64_ftr_reg() returns the properties of a system register based
on its instruction encoding.

This is needed by erratum workaround in cpu_errata.c to modify the
user-space visible view of id registers.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220909165938.3931307-3-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 15:16:34 +01:00
James Morse
237405ebef arm64: cpufeature: Force HWCAP to be based on the sysreg visible to user-space
arm64 advertises hardware features to user-space via HWCAPs, and by
emulating access to the CPUs id registers. The cpufeature code has a
sanitised system-wide view of an id register, and a sanitised user-space
view of an id register, where some features use their 'safe' value
instead of the hardware value.

It is currently possible for a HWCAP to be advertised where the user-space
view of the id register does not show the feature as supported.
Erratum workaround need to remove both the HWCAP, and the feature from
the user-space view of the id register. This involves duplicating the
code, and spreading it over cpufeature.c and cpu_errata.c.

Make the HWCAP code use the user-space view of id registers. This ensures
the values never diverge, and allows erratum workaround to remove HWCAP
by modifying the user-space view of the id register.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220909165938.3931307-2-james.morse@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 15:16:34 +01:00
Mark Brown
fcf37b38ff arm64/sysreg: Add _EL1 into ID_AA64DFR0_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64DFR0_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220910163354.860255-3-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 12:38:57 +01:00
Mark Brown
c0357a73fa arm64/sysreg: Align field names in ID_AA64DFR0_EL1 with architecture
The naming scheme the architecture uses for the fields in ID_AA64DFR0_EL1
does not align well with kernel conventions, using as it does a lot of
MixedCase in various arrangements. In preparation for automatically
generating the defines for this register rename the defines used to match
what is in the architecture.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220910163354.860255-2-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-16 12:38:57 +01:00
Mark Brown
ed9075201c arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 SME enumeration
In preparation for automatic generation of constants update the define for
SME being implemented to the convention we are using, no functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-20-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:04 +01:00
Mark Brown
514e9b2aed arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 BTI enumeration
In preparation for automatic generation of constants update the define for
BTI being implemented to the convention we are using, no functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-19-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:04 +01:00
Mark Brown
cf7fdbbe83 arm64/sysreg: Standardise naming of ID_AA64PFR1_EL1 fractional version fields
The naming for fractional versions fields in ID_AA64PFR1_EL1 does not align
with that in the architecture, lacking underscores and using upper case
where the architecture uses lower case. In preparation for automatic
generation of defines bring the code in sync with the architecture, no
functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-18-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:04 +01:00
Mark Brown
2e75b393ff arm64/sysreg: Standardise naming for MTE feature enumeration
In preparation for conversion to automatic generation refresh the names
given to the items in the MTE feture enumeration to reflect our standard
pattern for naming, corresponding to the architecture feature names they
reflect. No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-17-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:04 +01:00
Mark Brown
53275da8dc arm64/sysreg: Standardise naming for SSBS feature enumeration
In preparation for conversion to automatic generation refresh the names
given to the items in the SSBS feature enumeration to reflect our standard
pattern for naming, corresponding to the architecture feature names they
reflect. No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-16-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Mark Brown
5620b4b037 arm64/sysreg: Standardise naming for ID_AA64PFR0_EL1.AdvSIMD constants
The architecture refers to the register field identifying advanced SIMD as
AdvSIMD but the kernel refers to it as ASIMD. Use the architecture's
naming. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-15-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Mark Brown
4f8456c319 arm64/sysreg: Standardise naming for ID_AA64PFR0_EL1 constants
We generally refer to the baseline feature implemented as _IMP so in
preparation for automatic generation of register defines update those for
ID_AA64PFR0_EL1 to reflect this.

In the case of ASIMD we don't actually use the define so just remove it.

No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-14-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Mark Brown
ca951862ad arm64/sysreg: Standardise naming for ID_AA64MMFR2_EL1.CnP
The kernel refers to ID_AA64MMFR2_EL1.CnP as CNP. In preparation for
automatic generation of defines for the system registers bring the naming
used by the kernel in sync with that of DDI0487H.a. No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-13-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Mark Brown
8f40baded4 arm64/sysreg: Standardise naming for ID_AA64MMFR2_EL1.VARange
The kernel refers to ID_AA64MMFR2_EL1.VARange as LVA. In preparation for
automatic generation of defines for the system registers bring the naming
used by the kernel in sync with that of DDI0487H.a. No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-12-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Kristina Martsenko
6fcd019359 arm64/sysreg: Standardise naming for ID_AA64MMFR1_EL1 fields
In preparation for converting the ID_AA64MMFR1_EL1 system register
defines to automatic generation, rename them to follow the conventions
used by other automatically generated registers:

 * Add _EL1 in the register name.

 * Rename fields to match the names in the ARM ARM:
   * LOR -> LO
   * HPD -> HPDS
   * VHE -> VH
   * HADBS -> HAFDBS
   * SPECSEI -> SpecSEI
   * VMIDBITS -> VMIDBits

There should be no functional change as a result of this patch.

Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-11-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:03 +01:00
Mark Brown
07d7d848b9 arm64/sysreg: Standardise naming of ID_AA64MMFR0_EL1.ASIDBits
For some reason we refer to ID_AA64MMFR0_EL1.ASIDBits as ASID. Add BITS
into the name, bringing the naming into sync with DDI0487H.a. Due to the
large amount of MixedCase in this register which isn't really consistent
with either the kernel style or the majority of the architecture the use of
upper case is preserved. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-10-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
ed7c138d6f arm64/sysreg: Standardise naming of ID_AA64MMFR0_EL1.BigEnd
For some reason we refer to ID_AA64MMFR0_EL1.BigEnd as BIGENDEL. Remove the
EL from the name, bringing the naming into sync with DDI0487H.a. Due to the
large amount of MixedCase in this register which isn't really consistent
with either the kernel style or the majority of the architecture the use of
upper case is preserved. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-9-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
6ca2b9ca45 arm64/sysreg: Add _EL1 into ID_AA64PFR1_EL1 constant names
Our standard is to include the _EL1 in the constant names for registers but
we did not do that for ID_AA64PFR1_EL1, update to do so in preparation for
conversion to automatic generation. No functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-8-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
55adc08d7e arm64/sysreg: Add _EL1 into ID_AA64PFR0_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64PFR0_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-7-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
a957c6be2b arm64/sysreg: Add _EL1 into ID_AA64MMFR2_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64MMFR2_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-6-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
2d987e64e8 arm64/sysreg: Add _EL1 into ID_AA64MMFR0_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64MMFR0_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-5-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-09 10:59:02 +01:00
Mark Brown
81ff692ad9 arm64/sysreg: Add hwcap for SVE EBF16
SVE has a separate identification register indicating support for BFloat16
operations. Add a hwcap identifying support for EBF16 in this register,
mirroring what we did for the non-SVE case.

While there is currently an architectural requirement for BF16 support to
be the same in SVE and non-SVE contexts there are separate identification
registers this separate hwcap helps avoid issues if that requirement were
to be relaxed in the future, we have already chosen to have a separate
capability for base BF16 support.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220829154815.832347-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-06 18:53:52 +01:00
Ionela Voinescu
e89d120c4b arm64: errata: add detection for AMEVCNTR01 incrementing incorrectly
The AMU counter AMEVCNTR01 (constant counter) should increment at the same
rate as the system counter. On affected Cortex-A510 cores, AMEVCNTR01
increments incorrectly giving a significantly higher output value. This
results in inaccurate task scheduler utilization tracking and incorrect
feedback on CPU frequency.

Work around this problem by returning 0 when reading the affected counter
in key locations that results in disabling all users of this counter from
using it either for frequency invariance or as FFH reference counter. This
effect is the same to firmware disabling affected counters.

Details on how the two features are affected by this erratum:

 - AMU counters will not be used for frequency invariance for affected
   CPUs and CPUs in the same cpufreq policy. AMUs can still be used for
   frequency invariance for unaffected CPUs in the system. Although
   unlikely, if no alternative method can be found to support frequency
   invariance for affected CPUs (cpufreq based or solution based on
   platform counters) frequency invariance will be disabled. Please check
   the chapter on frequency invariance at
   Documentation/scheduler/sched-capacity.rst for details of its effect.

 - Given that FFH can be used to fetch either the core or constant counter
   values, restrictions are lifted regarding any of these counters
   returning a valid (!0) value. Therefore FFH is considered supported
   if there is a least one CPU that support AMUs, independent of any
   counters being disabled or affected by this erratum. Clarifying
   comments are now added to the cpc_ffh_supported(), cpu_read_constcnt()
   and cpu_read_corecnt() functions.

The above is achieved through adding a new erratum: ARM64_ERRATUM_2457168.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220819103050.24211-1-ionela.voinescu@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-08-23 11:06:48 +01:00
Linus Torvalds
a0b09f2d6f Random number generator updates for Linux 6.0-rc1.
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Merge tag 'random-6.0-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

Pull random number generator updates from Jason Donenfeld:
 "Though there's been a decent amount of RNG-related development during
  this last cycle, not all of it is coming through this tree, as this
  cycle saw a shift toward tackling early boot time seeding issues,
  which took place in other trees as well.

  Here's a summary of the various patches:

   - The CONFIG_ARCH_RANDOM .config option and the "nordrand" boot
     option have been removed, as they overlapped with the more widely
     supported and more sensible options, CONFIG_RANDOM_TRUST_CPU and
     "random.trust_cpu". This change allowed simplifying a bit of arch
     code.

   - x86's RDRAND boot time test has been made a bit more robust, with
     RDRAND disabled if it's clearly producing bogus results. This would
     be a tip.git commit, technically, but I took it through random.git
     to avoid a large merge conflict.

   - The RNG has long since mixed in a timestamp very early in boot, on
     the premise that a computer that does the same things, but does so
     starting at different points in wall time, could be made to still
     produce a different RNG state. Unfortunately, the clock isn't set
     early in boot on all systems, so now we mix in that timestamp when
     the time is actually set.

   - User Mode Linux now uses the host OS's getrandom() syscall to
     generate a bootloader RNG seed and later on treats getrandom() as
     the platform's RDRAND-like faculty.

   - The arch_get_random_{seed_,}_long() family of functions is now
     arch_get_random_{seed_,}_longs(), which enables certain platforms,
     such as s390, to exploit considerable performance advantages from
     requesting multiple CPU random numbers at once, while at the same
     time compiling down to the same code as before on platforms like
     x86.

   - A small cleanup changing a cmpxchg() into a try_cmpxchg(), from
     Uros.

   - A comment spelling fix"

More info about other random number changes that come in through various
architecture trees in the full commentary in the pull request:

  https://lore.kernel.org/all/20220731232428.2219258-1-Jason@zx2c4.com/

* tag 'random-6.0-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random:
  random: correct spelling of "overwrites"
  random: handle archrandom with multiple longs
  um: seed rng using host OS rng
  random: use try_cmpxchg in _credit_init_bits
  timekeeping: contribute wall clock to rng on time change
  x86/rdrand: Remove "nordrand" flag in favor of "random.trust_cpu"
  random: remove CONFIG_ARCH_RANDOM
2022-08-02 17:31:35 -07:00
Marc Zyngier
892f7237b3 arm64: Delay initialisation of cpuinfo_arm64::reg_{zcr,smcr}
Even if we are now able to tell the kernel to avoid exposing SVE/SME
from the command line, we still have a couple of places where we
unconditionally access the ZCR_EL1 (resp. SMCR_EL1) registers.

On systems with broken firmwares, this results in a crash even if
arm64.nosve (resp. arm64.nosme) was passed on the command-line.

To avoid this, only update cpuinfo_arm64::reg_{zcr,smcr} once
we have computed the sanitised version for the corresponding
feature registers (ID_AA64PFR0 for SVE, and ID_AA64PFR1 for
SME). This results in some minor refactoring.

Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Peter Collingbourne <pcc@google.com>
Tested-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220720105219.1755096-1-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-25 11:02:11 +01:00
Will Deacon
f96d67a8af Merge branch 'for-next/boot' into for-next/core
* for-next/boot: (34 commits)
  arm64: fix KASAN_INLINE
  arm64: Add an override for ID_AA64SMFR0_EL1.FA64
  arm64: Add the arm64.nosve command line option
  arm64: Add the arm64.nosme command line option
  arm64: Expose a __check_override primitive for oddball features
  arm64: Allow the idreg override to deal with variable field width
  arm64: Factor out checking of a feature against the override into a macro
  arm64: Allow sticky E2H when entering EL1
  arm64: Save state of HCR_EL2.E2H before switch to EL1
  arm64: Rename the VHE switch to "finalise_el2"
  arm64: mm: fix booting with 52-bit address space
  arm64: head: remove __PHYS_OFFSET
  arm64: lds: use PROVIDE instead of conditional definitions
  arm64: setup: drop early FDT pointer helpers
  arm64: head: avoid relocating the kernel twice for KASLR
  arm64: kaslr: defer initialization to initcall where permitted
  arm64: head: record CPU boot mode after enabling the MMU
  arm64: head: populate kernel page tables with MMU and caches on
  arm64: head: factor out TTBR1 assignment into a macro
  arm64: idreg-override: use early FDT mapping in ID map
  ...
2022-07-25 10:59:15 +01:00
Will Deacon
92867739e3 Merge branch 'for-next/cpufeature' into for-next/core
* for-next/cpufeature:
  arm64/hwcap: Support FEAT_EBF16
  arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
  arm64/hwcap: Document allocation of upper bits of AT_HWCAP
  arm64: trap implementation defined functionality in userspace
2022-07-25 10:58:10 +01:00
Will Deacon
618ff55eec Merge branch 'for-next/sysregs' into for-next/core
* for-next/sysregs: (28 commits)
  arm64/sysreg: Convert ID_AA64ZFR0_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64SMFR0_EL1 to automatic generation
  arm64/sysreg: Convert LORID_EL1 to automatic generation
  arm64/sysreg: Convert LORC_EL1 to automatic generation
  arm64/sysreg: Convert LORN_EL1 to automatic generation
  arm64/sysreg: Convert LOREA_EL1 to automatic generation
  arm64/sysreg: Convert LORSA_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64ISAR2_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64ISAR1_EL1 to automatic generation
  arm64/sysreg: Convert GMID to automatic generation
  arm64/sysreg: Convert DCZID_EL0 to automatic generation
  arm64/sysreg: Convert CTR_EL0 to automatic generation
  arm64/sysreg: Add _EL1 into ID_AA64ISAR2_EL1 definition names
  arm64/sysreg: Add _EL1 into ID_AA64ISAR1_EL1 definition names
  arm64/sysreg: Remove defines for RPRES enumeration
  arm64/sysreg: Standardise naming for ID_AA64ZFR0_EL1 fields
  arm64/sysreg: Standardise naming for ID_AA64SMFR0_EL1 enums
  arm64/sysreg: Standardise naming for WFxT defines
  arm64/sysreg: Make BHB clear feature defines match the architecture
  arm64/sysreg: Align pointer auth enumeration defines with architecture
  ...
2022-07-25 10:57:37 +01:00
Will Deacon
288e21b6b2 Merge branch 'for-next/perf' into for-next/core
* for-next/perf:
  drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX
  perf: RISC-V: Add of_node_put() when breaking out of for_each_of_cpu_node()
  docs: perf: Include hns3-pmu.rst in toctree to fix 'htmldocs' WARNING
  drivers/perf: hisi: add driver for HNS3 PMU
  drivers/perf: hisi: Add description for HNS3 PMU driver
  drivers/perf: riscv_pmu_sbi: perf format
  perf/arm-cci: Use the bitmap API to allocate bitmaps
  drivers/perf: riscv_pmu: Add riscv pmu pm notifier
  perf: hisi: Extract hisi_pmu_init
  perf/marvell_cn10k: Fix TAD PMU register offset
  perf/marvell_cn10k: Remove useless license text when SPDX-License-Identifier is already used
  arm64: cpufeature: Allow different PMU versions in ID_DFR0_EL1
  perf/arm-cci: fix typo in comment
  drivers/perf:Directly use ida_alloc()/free()
  drivers/perf: Directly use ida_alloc()/free()
2022-07-25 10:57:14 +01:00
Will Deacon
8184a8bc1c Merge branch 'for-next/kpti' into for-next/core
* for-next/kpti:
  arm64: correct the effect of mitigations off on kpti
  arm64: entry: simplify trampoline data page
  arm64: mm: install KPTI nG mappings with MMU enabled
  arm64: kpti-ng: simplify page table traversal logic
2022-07-25 10:56:49 +01:00
Mark Brown
a6a468f50d arm64/hwcap: Support FEAT_EBF16
The v9.2 feature FEAT_EBF16 provides support for an extended BFloat16 mode.
Allow userspace to discover system support for this feature by adding a
hwcap for it.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220707103632.12745-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-20 11:18:11 +01:00
Mark Brown
60c868eff2 arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
When we added support for AT_HWCAP2 we took advantage of the fact that we
have limited hwcaps to the low 32 bits and stored it along with AT_HWCAP
in a single unsigned integer. Thanks to the ever expanding capabilities of
the architecture we have now allocated all 64 of the bits in an unsigned
long so in preparation for adding more hwcaps convert elf_hwcap to be a
bitmap instead, with 64 bits allocated to each AT_HWCAP.

There should be no functional change from this patch.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220707103632.12745-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-20 11:18:11 +01:00
James Morse
44b3834b2e arm64: errata: Remove AES hwcap for COMPAT tasks
Cortex-A57 and Cortex-A72 have an erratum where an interrupt that
occurs between a pair of AES instructions in aarch32 mode may corrupt
the ELR. The task will subsequently produce the wrong AES result.

The AES instructions are part of the cryptographic extensions, which are
optional. User-space software will detect the support for these
instructions from the hwcaps. If the platform doesn't support these
instructions a software implementation should be used.

Remove the hwcap bits on affected parts to indicate user-space should
not use the AES instructions.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220714161523.279570-3-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-19 19:27:01 +01:00
Jason A. Donenfeld
9592eef7c1 random: remove CONFIG_ARCH_RANDOM
When RDRAND was introduced, there was much discussion on whether it
should be trusted and how the kernel should handle that. Initially, two
mechanisms cropped up, CONFIG_ARCH_RANDOM, a compile time switch, and
"nordrand", a boot-time switch.

Later the thinking evolved. With a properly designed RNG, using RDRAND
values alone won't harm anything, even if the outputs are malicious.
Rather, the issue is whether those values are being *trusted* to be good
or not. And so a new set of options were introduced as the real
ones that people use -- CONFIG_RANDOM_TRUST_CPU and "random.trust_cpu".
With these options, RDRAND is used, but it's not always credited. So in
the worst case, it does nothing, and in the best case, maybe it helps.

Along the way, CONFIG_ARCH_RANDOM's meaning got sort of pulled into the
center and became something certain platforms force-select.

The old options don't really help with much, and it's a bit odd to have
special handling for these instructions when the kernel can deal fine
with the existence or untrusted existence or broken existence or
non-existence of that CPU capability.

Simplify the situation by removing CONFIG_ARCH_RANDOM and using the
ordinary asm-generic fallback pattern instead, keeping the two options
that are actually used. For now it leaves "nordrand" for now, as the
removal of that will take a different route.

Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-07-18 15:03:37 +02:00
Mark Brown
b2d71f275d arm64/sysreg: Add _EL1 into ID_AA64ISAR2_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64ISAR2_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-17-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-05 11:45:46 +01:00
Mark Brown
aa50479b4f arm64/sysreg: Add _EL1 into ID_AA64ISAR1_EL1 definition names
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64ISAR1_EL1 to follow the convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-16-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-05 11:45:46 +01:00
Mark Brown
8d8feb0eae arm64/sysreg: Standardise naming for ID_AA64ZFR0_EL1 fields
The various defines for bitfields in ID_AA64ZFR0_EL1 do not follow our
conventions for register field names, they omit the _EL1, they don't use
specific defines for enumeration values and they don't follow the naming
in the architecture in some cases. In preparation for automatic generation
bring them into line with convention. No functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-14-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-05 11:45:46 +01:00