platform/kernel/linux-rpi.git
3 years agoMerge branch 'for-next/selftests' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:06:38 +0000 (14:06 +0100)]
Merge branch 'for-next/selftests' into for-next/core

Fix output format from SVE selftest.

* for-next/selftests:
  kselftest/arm64: Add missing newline to SVE test skipping output

3 years agoMerge branch 'for-next/ptrauth' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:06:23 +0000 (14:06 +0100)]
Merge branch 'for-next/ptrauth' into for-next/core

Allow Pointer Authentication to be configured independently for kernel
and userspace.

* for-next/ptrauth:
  arm64: Conditionally configure PTR_AUTH key of the kernel.
  arm64: Add ARM64_PTR_AUTH_KERNEL config option

3 years agoMerge branch 'for-next/perf' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:05:40 +0000 (14:05 +0100)]
Merge branch 'for-next/perf' into for-next/core

PMU driver cleanups for managing IRQ affinity and exposing event
attributes via sysfs.

* for-next/perf: (36 commits)
  drivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe()
  perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number
  arm64: perf: Simplify EVENT ATTR macro in perf_event.c
  drivers/perf: Simplify EVENT ATTR macro in fsl_imx8_ddr_perf.c
  drivers/perf: Simplify EVENT ATTR macro in xgene_pmu.c
  drivers/perf: Simplify EVENT ATTR macro in qcom_l3_pmu.c
  drivers/perf: Simplify EVENT ATTR macro in qcom_l2_pmu.c
  drivers/perf: Simplify EVENT ATTR macro in SMMU PMU driver
  perf: Add EVENT_ATTR_ID to simplify event attributes
  perf/smmuv3: Don't trample existing events with global filter
  perf/hisi: Constify static attribute_group structs
  perf: qcom: Remove redundant dev_err call in qcom_l3_cache_pmu_probe()
  drivers/perf: hisi: Fix data source control
  arm64: perf: Add more support on caps under sysfs
  perf: qcom_l2_pmu: move to use request_irq by IRQF_NO_AUTOEN flag
  arm_pmu: move to use request_irq by IRQF_NO_AUTOEN flag
  perf: arm_spe: use DEVICE_ATTR_RO macro
  perf: xgene_pmu: use DEVICE_ATTR_RO macro
  perf: qcom: use DEVICE_ATTR_RO macro
  perf: arm_pmu: use DEVICE_ATTR_RO macro
  ...

3 years agoMerge branch 'for-next/mte' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:05:25 +0000 (14:05 +0100)]
Merge branch 'for-next/mte' into for-next/core

KASAN optimisations for the hardware tagging (MTE) implementation.

* for-next/mte:
  kasan: disable freed user page poisoning with HW tags
  arm64: mte: handle tags zeroing at page allocation time
  kasan: use separate (un)poison implementation for integrated init
  mm: arch: remove indirection level in alloc_zeroed_user_highpage_movable()
  kasan: speed up mte_set_mem_tag_range

3 years agoMerge branch 'for-next/mm' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:04:33 +0000 (14:04 +0100)]
Merge branch 'for-next/mm' into for-next/core

Lots of cleanup to our various page-table definitions, but also some
non-critical fixes and removal of some unnecessary memory types. The
most interesting change here is the reduction of ARCH_DMA_MINALIGN back
to 64 bytes, since we're not aware of any machines that need a higher
value with the way the code is structured (only needed for non-coherent
DMA).

* for-next/mm:
  arm64: tlb: fix the TTL value of tlb_get_level
  arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS
  arm64: head: fix code comments in set_cpu_boot_mode_flag
  arm64: mm: drop unused __pa(__idmap_text_start)
  arm64: mm: fix the count comments in compute_indices
  arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan
  arm64: mm: Pass original fault address to handle_mm_fault()
  arm64/mm: Drop SECTION_[SHIFT|SIZE|MASK]
  arm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT
  arm64/mm: Drop SWAPPER_INIT_MAP_SIZE
  arm64: mm: decode xFSC in mem_abort_decode()
  arm64: mm: Add is_el1_data_abort() helper
  arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)
  arm64: mm: Remove unused support for Normal-WT memory type
  arm64: acpi: Map EFI_MEMORY_WT memory as Normal-NC
  arm64: mm: Remove unused support for Device-GRE memory type
  arm64: mm: Use better bitmap_zalloc()
  arm64/mm: Make vmemmap_free() available only with CONFIG_MEMORY_HOTPLUG
  arm64/mm: Remove [PUD|PMD]_TABLE_BIT from [pud|pmd]_bad()
  arm64/mm: Validate CONFIG_PGTABLE_LEVELS

3 years agoMerge branch 'for-next/misc' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:04:19 +0000 (14:04 +0100)]
Merge branch 'for-next/misc' into for-next/core

Reduce loglevel of useless print during CPU offlining.

* for-next/misc:
  arm64: smp: Bump debugging information print down to KERN_DEBUG

3 years agoMerge branch 'for-next/kasan' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:04:00 +0000 (14:04 +0100)]
Merge branch 'for-next/kasan' into for-next/core

Optimise out-of-line KASAN checking when using software tagging.

* for-next/kasan:
  kasan: arm64: support specialized outlined tag mismatch checks

3 years agoMerge branch 'for-next/insn' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:03:24 +0000 (14:03 +0100)]
Merge branch 'for-next/insn' into for-next/core

Refactoring of our instruction decoding routines and addition of some
missing encodings.

* for-next/insn:
  arm64: insn: avoid circular include dependency
  arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>
  arm64: insn: decouple patching from insn code
  arm64: insn: Add load/store decoding helpers
  arm64: insn: Add some opcodes to instruction decoder
  arm64: insn: Add barrier encodings
  arm64: insn: Add SVE instruction class
  arm64: Move instruction encoder/decoder under lib/
  arm64: Move aarch32 condition check functions
  arm64: Move patching utilities out of instruction encoding/decoding

3 years agoMerge branch 'for-next/entry' into for-next/core
Will Deacon [Thu, 24 Jun 2021 13:01:55 +0000 (14:01 +0100)]
Merge branch 'for-next/entry' into for-next/core

The never-ending entry.S refactoring continues, putting us in a much
better place wrt compiler instrumentation whilst moving more of the code
into C.

* for-next/entry:
  arm64: idle: don't instrument idle code with KCOV
  arm64: entry: don't instrument entry code with KCOV
  arm64: entry: make NMI entry/exit functions static
  arm64: entry: split SDEI entry
  arm64: entry: split bad stack entry
  arm64: entry: fold el1_inv() into el1h_64_sync_handler()
  arm64: entry: handle all vectors with C
  arm64: entry: template the entry asm functions
  arm64: entry: improve bad_mode()
  arm64: entry: move bad_mode() to entry-common.c
  arm64: entry: consolidate EL1 exception returns
  arm64: entry: organise entry vectors consistently
  arm64: entry: organise entry handlers consistently
  arm64: entry: convert IRQ+FIQ handlers to C
  arm64: entry: add a call_on_irq_stack helper
  arm64: entry: move NMI preempt logic to C
  arm64: entry: move arm64_preempt_schedule_irq to entry-common.c
  arm64: entry: convert SError handlers to C
  arm64: entry: unmask IRQ+FIQ after EL0 handling
  arm64: remove redundant local_daif_mask() in bad_mode()

3 years agoMerge branch 'for-next/docs' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:37:47 +0000 (13:37 +0100)]
Merge branch 'for-next/docs' into for-next/core

Update booting requirements for the FEAT_HCX feature, added to v8.7 of
the architecture.

* for-next/docs:
  arm64: Document requirement for access to FEAT_HCX

3 years agoMerge branch 'for-next/cpuidle' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:36:39 +0000 (13:36 +0100)]
Merge branch 'for-next/cpuidle' into for-next/core

Fix resume from idle when pNMI is being used.

* for-next/cpuidle:
  arm64: suspend: Use cpuidle context helpers in cpu_suspend()
  PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()
  arm64: Convert cpu_do_idle() to using cpuidle context helpers
  arm64: Add cpuidle context save/restore helpers

3 years agoMerge branch 'for-next/cpufeature' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:35:46 +0000 (13:35 +0100)]
Merge branch 'for-next/cpufeature' into for-next/core

Additional CPU sanity checks for MTE and preparatory changes for systems
where not all of the CPUs support 32-bit EL0.

* for-next/cpufeature:
  arm64: Restrict undef hook for cpufeature registers
  arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs
  KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support
  arm64: Allow mismatched 32-bit EL0 support
  arm64: cpuinfo: Split AArch32 registers out into a separate struct
  arm64: Check if GMID_EL1.BS is the same on all CPUs
  arm64: Change the cpuinfo_arm64 member type for some sysregs to u64

3 years agoMerge branch 'for-next/cortex-strings' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:33:57 +0000 (13:33 +0100)]
Merge branch 'for-next/cortex-strings' into for-next/core

Update our kernel string routines to the latest Cortex Strings
implementation.

* for-next/cortex-strings:
  arm64: update string routine copyrights and URLs
  arm64: Rewrite __arch_clear_user()
  arm64: Better optimised memchr()
  arm64: Import latest memcpy()/memmove() implementation
  arm64: Add assembly annotations for weak-PI-alias madness
  arm64: Import latest version of Cortex Strings' strncmp
  arm64: Import updated version of Cortex Strings' strlen
  arm64: Import latest version of Cortex Strings' strcmp
  arm64: Import latest version of Cortex Strings' memcmp

3 years agoMerge branch 'for-next/caches' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:33:02 +0000 (13:33 +0100)]
Merge branch 'for-next/caches' into for-next/core

Big cleanup of our cache maintenance routines, which were confusingly
named and inconsistent in their implementations.

* for-next/caches:
  arm64: Rename arm64-internal cache maintenance functions
  arm64: Fix cache maintenance function comments
  arm64: sync_icache_aliases to take end parameter instead of size
  arm64: __clean_dcache_area_pou to take end parameter instead of size
  arm64: __clean_dcache_area_pop to take end parameter instead of size
  arm64: __clean_dcache_area_poc to take end parameter instead of size
  arm64: __flush_dcache_area to take end parameter instead of size
  arm64: dcache_by_line_op to take end parameter instead of size
  arm64: __inval_dcache_area to take end parameter instead of size
  arm64: Fix comments to refer to correct function __flush_icache_range
  arm64: Move documentation of dcache_by_line_op
  arm64: assembler: remove user_alt
  arm64: Downgrade flush_icache_range to invalidate
  arm64: Do not enable uaccess for invalidate_icache_range
  arm64: Do not enable uaccess for flush_icache_range
  arm64: Apply errata to swsusp_arch_suspend_exit
  arm64: assembler: add conditional cache fixups
  arm64: assembler: replace `kaddr` with `addr`

3 years agoMerge branch 'for-next/build' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:31:41 +0000 (13:31 +0100)]
Merge branch 'for-next/build' into for-next/core

Tweak linker flags so that GDB can understand vmlinux when using RELR
relocations.

* for-next/build:
  Makefile: fix GDB warning with CONFIG_RELR

3 years agoMerge branch 'for-next/boot' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:30:13 +0000 (13:30 +0100)]
Merge branch 'for-next/boot' into for-next/core

Boot path cleanups to enable early initialisation of per-cpu operations
needed by KCSAN.

* for-next/boot:
  arm64: scs: Drop unused 'tmp' argument to scs_{load, save} asm macros
  arm64: smp: initialize cpu offset earlier
  arm64: smp: unify task and sp setup
  arm64: smp: remove stack from secondary_data
  arm64: smp: remove pointless secondary_data maintenance
  arm64: assembler: add set_this_cpu_offset

3 years agoMerge branch 'for-next/stacktrace' into for-next/core
Will Deacon [Thu, 24 Jun 2021 12:15:09 +0000 (13:15 +0100)]
Merge branch 'for-next/stacktrace' into for-next/core

Relax frame record alignment requirements to facilitate 8-byte alignment
with KASAN and Clang.

* for-next/stacktrace:
  arm64: stacktrace: Relax frame record alignment requirement to 8 bytes
  arm64: Change the on_*stack functions to take a size argument
  arm64: Implement stack trace termination record

3 years agoarm64: tlb: fix the TTL value of tlb_get_level
Zhenyu Ye [Wed, 23 Jun 2021 07:05:22 +0000 (15:05 +0800)]
arm64: tlb: fix the TTL value of tlb_get_level

The TTL field indicates the level of page table walk holding the *leaf*
entry for the address being invalidated. But currently, the TTL field
may be set to an incorrent value in the following stack:

pte_free_tlb
    __pte_free_tlb
        tlb_remove_table
            tlb_table_invalidate
                tlb_flush_mmu_tlbonly
                    tlb_flush

In this case, we just want to flush a PTE page, but the tlb->cleared_pmds
is set and we get tlb_level = 2 in the tlb_get_level() function. This may
cause some unexpected problems.

This patch set the TTL field to 0 if tlb->freed_tables is set. The
tlb->freed_tables indicates page table pages are freed, not the leaf
entry.

Cc: <stable@vger.kernel.org> # 5.9.x
Fixes: c4ab2cbc1d87 ("arm64: tlb: Set the TTL field in flush_tlb_range")
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: ZhuRui <zhurui3@huawei.com>
Signed-off-by: Zhenyu Ye <yezhenyu2@huawei.com>
Link: https://lore.kernel.org/r/b80ead47-1f88-3a00-18e1-cacc22f54cc4@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Restrict undef hook for cpufeature registers
Raphael Gault [Mon, 17 May 2021 18:02:56 +0000 (13:02 -0500)]
arm64: Restrict undef hook for cpufeature registers

This commit modifies the mask of the mrs_hook declared in
arch/arm64/kernel/cpufeatures.c which emulates only feature register
access. This is necessary because this hook's mask was too large and
thus masking any mrs instruction, even if not related to the emulated
registers which made the pmu emulation inefficient.

Signed-off-by: Raphael Gault <raphael.gault@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210517180256.2881891-1-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS
Anshuman Khandual [Fri, 18 Jun 2021 04:47:02 +0000 (10:17 +0530)]
arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS

ARM64_SWAPPER_USES_SECTION_MAPS implies that a PMD level huge page mappings
are used for swapper, idmap and vmemmap. Lets make it PMD explicit removing
any possible confusion with generic memory sections and also bit generic as
it's applicable for idmap and vmemmap mappings as well. Hence rename it as
ARM64_KERNEL_USES_PMD_MAPS instead.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623991622-24294-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: insn: avoid circular include dependency
Mark Rutland [Fri, 18 Jun 2021 15:11:22 +0000 (16:11 +0100)]
arm64: insn: avoid circular include dependency

Nathan reports that when building with CONFIG_LTO_CLANG_THIN=y, the
build fails due to BUILD_BUG_ON() not being defined before its uss in
<asm/insn.h>.

The problem is that with LTO, we patch READ_ONCE(), and <asm/rwonce.h>
includes <asm/insn.h>, creating a circular include chain:

        <linux/build_bug.h>
        <linux/compiler.h>
        <asm/rwonce.h>
        <asm/alternative-macros.h>
        <asm/insn.h>
        <linux/build-bug.h>

... and so when <asm/insn.h> includes <linux/build_bug.h>, none of the
BUILD_BUG* definitions have happened yet.

To avoid this, let's move AARCH64_INSN_SIZE into a header without any
dependencies, such that it can always be safely included. At the same
time, avoid including <asm/alternative.h> in <asm/insn.h>, which should
no longer be necessary (and doesn't make sense when insn.h is consumed
by userspace).

Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210621080830.GA37068@C02TD0UTHF1T.local
Fixes: 3e00e39d9dad ("arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>")
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: smp: Bump debugging information print down to KERN_DEBUG
Lee Jones [Thu, 17 Jun 2021 07:30:59 +0000 (08:30 +0100)]
arm64: smp: Bump debugging information print down to KERN_DEBUG

This sort of information is only generally useful when debugging.

No need to have these sprinkled through the kernel log otherwise.

Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210617073059.315542-1-lee.jones@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe()
Jing Xiangfeng [Thu, 17 Jun 2021 12:26:14 +0000 (20:26 +0800)]
drivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe()

ddr_perf_probe() misses to call ida_simple_remove() in an error path.
Jump to cpuhp_state_err to fix it.

Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20210617122614.166823-1-jingxiangfeng@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number
Tuan Phan [Thu, 17 Jun 2021 16:08:49 +0000 (09:08 -0700)]
perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number

When multiple dtcs share the same IRQ number, the irq_friend which
used to refer to dtc object gets calculated incorrect which leads
to invalid pointer.

Fixes: 0ba64770a2f2 ("perf: Add Arm CMN-600 PMU driver")

Signed-off-by: Tuan Phan <tuanphan@os.amperecomputing.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1623946129-3290-1-git-send-email-tuanphan@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: suspend: Use cpuidle context helpers in cpu_suspend()
Marc Zyngier [Tue, 15 Jun 2021 11:12:27 +0000 (12:12 +0100)]
arm64: suspend: Use cpuidle context helpers in cpu_suspend()

Use cpuidle context helpers to switch to using DAIF.IF instead
of PMR to mask interrupts, ensuring that we suspend with
interrupts being able to reach the CPU interface.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20210615111227.2454465-5-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoPSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()
Marc Zyngier [Tue, 15 Jun 2021 11:12:26 +0000 (12:12 +0100)]
PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()

The PSCI CPU suspend code isn't aware of the PMR vs DAIF game,
resulting in a system that locks up if entering CPU suspend
with GICv3 pNMI enabled.

To save the day, teach the suspend code about our new cpuidle
context helpers, which will do everything that's required just
like the usual WFI cpuidle code.

This fixes my Altra system, which would otherwise lock-up at
boot time when booted with irqchip.gicv3_pseudo_nmi=1.

Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20210615111227.2454465-4-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Convert cpu_do_idle() to using cpuidle context helpers
Marc Zyngier [Tue, 15 Jun 2021 11:12:25 +0000 (12:12 +0100)]
arm64: Convert cpu_do_idle() to using cpuidle context helpers

Now that we have helpers that are aware of the pseudo-NMI
feature, introduce them to cpu_do_idle(). This allows for
some nice cleanup.

No functional change intended.

Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210615111227.2454465-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Add cpuidle context save/restore helpers
Marc Zyngier [Tue, 15 Jun 2021 11:12:24 +0000 (12:12 +0100)]
arm64: Add cpuidle context save/restore helpers

As we need to start doing some additional work on all idle
paths, let's introduce a set of macros that will perform
the work related to the GICv3 pseudo-NMI idle entry exit.

Stubs are introduced to 32bit ARM for compatibility.
As these helpers are currently unused, there is no functional
change.

Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210615111227.2454465-2-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: head: fix code comments in set_cpu_boot_mode_flag
Dong Aisheng [Tue, 18 May 2021 10:14:05 +0000 (18:14 +0800)]
arm64: head: fix code comments in set_cpu_boot_mode_flag

Up to here, the CPU boot mode can either be EL1 or EL2.
Correct the code comments a bit.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210518101405.1048860-5-aisheng.dong@nxp.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: drop unused __pa(__idmap_text_start)
Dong Aisheng [Tue, 18 May 2021 10:14:04 +0000 (18:14 +0800)]
arm64: mm: drop unused __pa(__idmap_text_start)

x5 is not used in the following map_memory. Instead,
__pa(__idmap_text_start) is stored in x3 which is used later.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210518101405.1048860-4-aisheng.dong@nxp.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: fix the count comments in compute_indices
Dong Aisheng [Tue, 18 May 2021 10:14:03 +0000 (18:14 +0800)]
arm64: mm: fix the count comments in compute_indices

'count - 1' is confusing and not comply with the real code running.
'count' actually represents the extra entries required, no need minus 1.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210518101405.1048860-3-aisheng.dong@nxp.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan
Anshuman Khandual [Tue, 15 Jun 2021 09:32:58 +0000 (15:02 +0530)]
arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan

When using CONFIG_ARM64_SW_TTBR0_PAN, a task's thread_info::ttbr0 must be
the TTBR0_EL1 value used to run userspace. With 52-bit PAs, the PA must be
packed into the TTBR using phys_to_ttbr(), but we forget to do this in some
of the SW PAN code. Thus, if the value is installed into TTBR0_EL1 (as may
happen in the uaccess routines), this could result in UNPREDICTABLE
behaviour.

Since hardware with 52-bit PA support almost certainly has HW PAN, which
will be used in preference, this shouldn't be a practical issue, but let's
fix this for consistency.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: 529c4b05a3cb ("arm64: handle 52-bit addresses in TTBR")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623749578-11231-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: Pass original fault address to handle_mm_fault()
Gavin Shan [Mon, 14 Jun 2021 12:27:01 +0000 (20:27 +0800)]
arm64: mm: Pass original fault address to handle_mm_fault()

Currently, the lower bits of fault address is cleared before it's
passed to handle_mm_fault(). It's unnecessary since generic code
does same thing since the commit 1a29d85eb0f19 ("mm: use vmf->address
instead of of vmf->virtual_address").

This passes the original fault address to handle_mm_fault() in case
the generic code needs to know the exact fault address.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20210614122701.100515-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64/mm: Drop SECTION_[SHIFT|SIZE|MASK]
Anshuman Khandual [Mon, 14 Jun 2021 08:18:26 +0000 (13:48 +0530)]
arm64/mm: Drop SECTION_[SHIFT|SIZE|MASK]

SECTION_[SHIFT|SIZE|MASK] are essentially PMD_[SHIFT|SIZE|MASK]. But these
create confusion being similar to generic sparsemem memory sections, which
are derived from SECTION_SIZE_BITS. Section references have always implied
PMD level block mapping. Instead just use all PMD level macros which would
make it explicit and also remove confusion with sparsmem memory sections.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623658706-7182-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT
Anshuman Khandual [Mon, 14 Jun 2021 09:42:35 +0000 (15:12 +0530)]
arm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT

ARM64_MEMSTART_SIZE needs to be aligned with CONT_PMD_SIZE on 16K page size
config. Hence just directly use CONT_PMD_SHIFT.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/1623663755-8949-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64/mm: Drop SWAPPER_INIT_MAP_SIZE
Anshuman Khandual [Mon, 14 Jun 2021 10:10:11 +0000 (15:40 +0530)]
arm64/mm: Drop SWAPPER_INIT_MAP_SIZE

The commit cdef5f6e9e0e ("arm64: mm: allocate pagetables anywhere") had
dropped the last reference to SWAPPER_INIT_MAP_SIZE. Hence just clean up.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Link: https://lore.kernel.org/r/1623665411-20055-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Conditionally configure PTR_AUTH key of the kernel.
Daniel Kiss [Sun, 13 Jun 2021 09:26:32 +0000 (11:26 +0200)]
arm64: Conditionally configure PTR_AUTH key of the kernel.

If the kernel is not compiled with CONFIG_ARM64_PTR_AUTH_KERNEL=y,
then no PACI/AUTI instructions are expected while the kernel is running
so the kernel's key will not be used. Write of a system registers
is expensive therefore avoid if not required.

Signed-off-by: Daniel Kiss <daniel.kiss@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210613092632.93591-3-daniel.kiss@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Add ARM64_PTR_AUTH_KERNEL config option
Daniel Kiss [Sun, 13 Jun 2021 09:26:31 +0000 (11:26 +0200)]
arm64: Add ARM64_PTR_AUTH_KERNEL config option

This patch add the ARM64_PTR_AUTH_KERNEL config and deals with the
build aspect of it.

Userspace support has no dependency on the toolchain therefore all
toolchain checks and build flags are controlled the new config
option.
The default config behavior will not be changed.

Signed-off-by: Daniel Kiss <daniel.kiss@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210613092632.93591-2-daniel.kiss@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Kill 32-bit applications scheduled on 64-bit-only CPUs
Will Deacon [Tue, 8 Jun 2021 18:02:57 +0000 (19:02 +0100)]
arm64: Kill 32-bit applications scheduled on 64-bit-only CPUs

Scheduling a 32-bit application on a 64-bit-only CPU is a bad idea.

Ensure that 32-bit applications always take the slow-path when returning
to userspace on a system with mismatched support at EL0, so that we can
avoid trying to run on a 64-bit-only CPU and force a SIGKILL instead.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-5-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoKVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support
Will Deacon [Tue, 8 Jun 2021 18:02:56 +0000 (19:02 +0100)]
KVM: arm64: Kill 32-bit vCPUs on systems with mismatched EL0 support

If a vCPU is caught running 32-bit code on a system with mismatched
support at EL0, then we should kill it.

Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-4-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Allow mismatched 32-bit EL0 support
Will Deacon [Tue, 8 Jun 2021 18:02:55 +0000 (19:02 +0100)]
arm64: Allow mismatched 32-bit EL0 support

When confronted with a mixture of CPUs, some of which support 32-bit
applications and others which don't, we quite sensibly treat the system
as 64-bit only for userspace and prevent execve() of 32-bit binaries.

Unfortunately, some crazy folks have decided to build systems like this
with the intention of running 32-bit applications, so relax our
sanitisation logic to continue to advertise 32-bit support to userspace
on these systems and track the real 32-bit capable cores in a cpumask
instead. For now, the default behaviour remains but will be tied to
a command-line option in a later patch.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-3-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: cpuinfo: Split AArch32 registers out into a separate struct
Will Deacon [Tue, 8 Jun 2021 18:02:54 +0000 (19:02 +0100)]
arm64: cpuinfo: Split AArch32 registers out into a separate struct

In preparation for late initialisation of the "sanitised" AArch32 register
state, move the AArch32 registers out of 'struct cpuinfo' and into their
own struct definition.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>
Mark Rutland [Wed, 9 Jun 2021 10:23:01 +0000 (11:23 +0100)]
arm64: insn: move AARCH64_INSN_SIZE into <asm/insn.h>

For histroical reasons, we define AARCH64_INSN_SIZE in
<asm/alternative-macros.h>, but it would make more sense to do so in
<asm/insn.h>. Let's move it into <asm/insn.h>, and add the necessary
include directives for this.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210609102301.17332-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: insn: decouple patching from insn code
Mark Rutland [Wed, 9 Jun 2021 10:23:00 +0000 (11:23 +0100)]
arm64: insn: decouple patching from insn code

Currently, <asm/insn.h> includes <asm/patching.h>. We intend that
<asm/insn.h> will be usable from userspace, so it doesn't make sense to
include headers for kernel-only features such as the patching routines,
and we'd intended to restrict <asm/insn.h> to instruction encoding
details.

Let's decouple the patching code from <asm/insn.h>, and explicitly
include <asm/patching.h> where it is needed. Since <asm/patching.h>
isn't included from assembly, we can drop the __ASSEMBLY__ guards.

At the same time, sort the kprobes includes so that it's easier to see
what is and isn't incldued.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210609102301.17332-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: perf: Simplify EVENT ATTR macro in perf_event.c
Qi Liu [Wed, 9 Jun 2021 06:41:03 +0000 (14:41 +0800)]
arm64: perf: Simplify EVENT ATTR macro in perf_event.c

Use common macro PMU_EVENT_ATTR_ID to simplify ARMV8_EVENT_ATTR

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-8-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: Simplify EVENT ATTR macro in fsl_imx8_ddr_perf.c
Qi Liu [Wed, 9 Jun 2021 06:41:02 +0000 (14:41 +0800)]
drivers/perf: Simplify EVENT ATTR macro in fsl_imx8_ddr_perf.c

Use common macro PMU_EVENT_ATTR_ID to simplify IMX8_DDR_PMU_EVENT_ATTR

Reviewed by Frank Li <Frank .li@nxp.com>

Cc: Frank Li <Frank.li@nxp.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-7-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: Simplify EVENT ATTR macro in xgene_pmu.c
Qi Liu [Wed, 9 Jun 2021 06:41:01 +0000 (14:41 +0800)]
drivers/perf: Simplify EVENT ATTR macro in xgene_pmu.c

Use common macro PMU_EVENT_ATTR_ID to simplify XGENE_PMU_EVENT_ATTR

Cc: Khuong Dinh <khuong@os.amperecomputing.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-6-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: Simplify EVENT ATTR macro in qcom_l3_pmu.c
Qi Liu [Wed, 9 Jun 2021 06:41:00 +0000 (14:41 +0800)]
drivers/perf: Simplify EVENT ATTR macro in qcom_l3_pmu.c

Use common macro PMU_EVENT_ATTR_ID to simplify L3CACHE_EVENT_ATTR

Cc: Andy Gross <agross@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-5-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: Simplify EVENT ATTR macro in qcom_l2_pmu.c
Qi Liu [Wed, 9 Jun 2021 06:40:59 +0000 (14:40 +0800)]
drivers/perf: Simplify EVENT ATTR macro in qcom_l2_pmu.c

Use common macro PMU_EVENT_ATTR_ID to simplify L2CACHE_EVENT_ATTR

Cc: Andy Gross <agross@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-4-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: Simplify EVENT ATTR macro in SMMU PMU driver
Qi Liu [Wed, 9 Jun 2021 06:40:58 +0000 (14:40 +0800)]
drivers/perf: Simplify EVENT ATTR macro in SMMU PMU driver

Use common macro PMU_EVENT_ATTR_ID to simplify SMMU_EVENT_ATTR

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-3-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf: Add EVENT_ATTR_ID to simplify event attributes
Qi Liu [Wed, 9 Jun 2021 06:40:57 +0000 (14:40 +0800)]
perf: Add EVENT_ATTR_ID to simplify event attributes

Similar EVENT_ATTR macros are defined in many PMU drivers,
like Arm PMU driver, Arm SMMU PMU driver. So add a generic
macro to simplify code.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1623220863-58233-2-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf/smmuv3: Don't trample existing events with global filter
Robin Murphy [Tue, 8 Jun 2021 11:55:12 +0000 (12:55 +0100)]
perf/smmuv3: Don't trample existing events with global filter

With global filtering, we only allow an event to be scheduled if its
filter settings exactly match those of any existing events, therefore
it is pointless to reapply the filter in that case. Much worse, though,
is that in doing that we trample the event type of counter 0 if it's
already active, and never touch the appropriate PMEVTYPERn so the new
event is likely not counting the right thing either. Don't do that.

CC: stable@vger.kernel.org
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/32c80c0e46237f49ad8da0c9f8864e13c4a803aa.1623153312.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: decode xFSC in mem_abort_decode()
Mark Rutland [Tue, 8 Jun 2021 12:37:42 +0000 (13:37 +0100)]
arm64: mm: decode xFSC in mem_abort_decode()

It would be helpful if mem_abort_decode() could decode the DFSC/IFSC, as
this can make it easier to identify common bugs (e.g. accesses which
trigger alignment faults) without having to manually decode the xFSC
value.

Decode the xFSC in mem_abort_decode().

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210608123742.11921-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoMakefile: fix GDB warning with CONFIG_RELR
Nick Desaulniers [Sat, 22 May 2021 01:26:24 +0000 (18:26 -0700)]
Makefile: fix GDB warning with CONFIG_RELR

GDB produces the following warning when debugging kernels built with
CONFIG_RELR:

BFD: /android0/linux-next/vmlinux: unknown type [0x13] section `.relr.dyn'

when loading a kernel built with CONFIG_RELR into GDB. It can also
prevent debugging symbols using such relocations.

Peter sugguests:
  [That flag] means that lld will use dynamic tags and section type
  numbers in the OS-specific range rather than the generic range. The
  kernel itself doesn't care about these numbers; it determines the
  location of the RELR section using symbols defined by a linker script.

Link: https://github.com/ClangBuiltLinux/linux/issues/1057
Suggested-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20210522012626.2811297-1-ndesaulniers@google.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf/hisi: Constify static attribute_group structs
Rikard Falkeborn [Sat, 5 Jun 2021 22:15:14 +0000 (00:15 +0200)]
perf/hisi: Constify static attribute_group structs

These are only put in an array of pointers to const attribute_group
structs. Make them const like the other static attribute_group structs
to allow the compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20210605221514.73449-1-rikard.falkeborn@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf: qcom: Remove redundant dev_err call in qcom_l3_cache_pmu_probe()
ChenXiaoSong [Tue, 8 Jun 2021 08:48:16 +0000 (16:48 +0800)]
perf: qcom: Remove redundant dev_err call in qcom_l3_cache_pmu_probe()

There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Link: https://lore.kernel.org/r/20210608084816.1046485-1-chenxiaosong2@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: idle: don't instrument idle code with KCOV
Mark Rutland [Mon, 7 Jun 2021 09:46:24 +0000 (10:46 +0100)]
arm64: idle: don't instrument idle code with KCOV

The low-level idle code in arch_cpu_idle() and its callees runs at a
time where where portions of the kernel environment aren't available.
For example, RCU may not be watching, and lockdep state may be
out-of-sync with the hardware. Due to this, it is not sound to
instrument this code.

We generally avoid instrumentation by marking the entry functions as
`noinstr`, but currently this doesn't inhibit KCOV instrumentation.
Prevent this by factoring these functions into a new idle.c so that we
can disable KCOV for the entire compilation unit, as is done for the
core idle code in kernel/sched/idle.c.

We'd like to keep instrumentation of the rest of process.c, and for the
existing code in cpuidle.c, so a new compilation unit is preferable. The
arch_cpu_idle_dead() function in process.c is a cpu hotplug function
that is safe to instrument, so it is left as-is in process.c.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-21-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: don't instrument entry code with KCOV
Mark Rutland [Mon, 7 Jun 2021 09:46:23 +0000 (10:46 +0100)]
arm64: entry: don't instrument entry code with KCOV

The code in entry-common.c runs at exception entry and return
boundaries, where portions of the kernel environment aren't available.
For example, RCU may not be watching, and lockdep state may be
out-of-sync with the hardware. Due to this, it is not sound to
instrument this code.

We generally avoid instrumentation by marking the entry functions as
`noinstr`, but currently this doesn't inhibit KCOV instrumentation.
Prevent this by disabling KCOV for the entire compilation unit.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-20-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: make NMI entry/exit functions static
Mark Rutland [Mon, 7 Jun 2021 09:46:22 +0000 (10:46 +0100)]
arm64: entry: make NMI entry/exit functions static

Now that we only call arm64_enter_nmi() and arm64_exit_nmi() from within
entry-common.c, let's make these static to ensure this remains the case.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-19-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: split SDEI entry
Mark Rutland [Mon, 7 Jun 2021 09:46:21 +0000 (10:46 +0100)]
arm64: entry: split SDEI entry

We'd like to keep all the entry sequencing in entry-common.c, as this
will allow us to ensure this is consistent, and free from any unsound
instrumentation.

Currently __sdei_handler() performs the NMI entry/exit sequences in
sdei.c. Let's split the low-level entry sequence from the event
handling, moving the former to entry-common.c and keeping the latter in
sdei.c. The event handling function is renamed to do_sdei_event(),
matching the do_${FOO}() pattern used for other exception handlers.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-18-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: split bad stack entry
Mark Rutland [Mon, 7 Jun 2021 09:46:20 +0000 (10:46 +0100)]
arm64: entry: split bad stack entry

We'd like to keep all the entry sequencing in entry-common.c, as this
will allow us to ensure this is consistent, and free from any unsound
instrumentation.

Currently handle_bad_stack() performs the NMI entry sequence in traps.c.
Let's split the low-level entry sequence from the reporting, moving the
former to entry-common.c and keeping the latter in traps.c. To make it
clear that reporting function never returns, it is renamed to
panic_bad_stack().

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-17-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: fold el1_inv() into el1h_64_sync_handler()
Mark Rutland [Mon, 7 Jun 2021 09:46:19 +0000 (10:46 +0100)]
arm64: entry: fold el1_inv() into el1h_64_sync_handler()

An unexpected synchronous exception from EL1h could happen at any time,
and for robustness we should treat this as an NMI, making minimal
assumptions about the context the exception was taken from.

Currently el1_inv() assumes we can use enter_from_kernel_mode(), and
also assumes that we should inherit the original DAIF value. Neither of
these are desireable when we take an unexpected exception. Further,
after el1_inv() calls __panic_unhandled(), the remainder of the function
is unreachable, and therefore superfluous.

Let's address this and simplify things by having el1h_64_sync_handler()
call __panic_unhandled() directly, without any of the redundant logic.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reported-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-16-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: handle all vectors with C
Mark Rutland [Mon, 7 Jun 2021 09:46:18 +0000 (10:46 +0100)]
arm64: entry: handle all vectors with C

We have 16 architectural exception vectors, and depending on kernel
configuration we handle 8 or 12 of these with C code, with the remaining
8 or 4 of these handled as special cases in the entry assembly.

It would be nicer if the entry assembly were uniform for all exceptions,
and we deferred any specific handling of the exceptions to C code. This
way the entry assembly can be more easily templated without ifdeffery or
special cases, and it's easier to modify the handling of these cases in
future (e.g. to dump additional registers other context).

This patch reworks the entry code so that we always have a C handler for
every architectural exception vector, with the entry assembly being
completely uniform. We now have to handle exceptions from EL1t and EL1h,
and also have to handle exceptions from AArch32 even when the kernel is
built without CONFIG_COMPAT. To make this clear and to simplify
templating, we rename the top-level exception handlers with a consistent
naming scheme:

  asm: <el+sp>_<regsize>_<type>
  c:   <el+sp>_<regsize>_<type>_handler

.. where:

  <el+sp> is `el1t`, `el1h`, or `el0t`
  <regsize> is `64` or `32`
  <type> is `sync`, `irq`, `fiq`, or `error`

... e.g.

  asm: el1h_64_sync
  c:   el1h_64_sync_handler

... with lower-level handlers simply using "el1" and "compat" as today.

For unexpected exceptions, this information is passed to
__panic_unhandled(), so it can report the specific vector an unexpected
exception was taken from, e.g.

| Unhandled 64-bit el1t sync exception

For vectors we never expect to enter legitimately, the C code is
generated using a macro to avoid code duplication. The exceptions are
handled via __panic_unhandled(), replacing bad_mode() (which is
removed).

The `kernel_ventry` and `entry_handler` assembly macros are updated to
handle the new naming scheme. In theory it should be possible to
generate the entry functions at the same time as the vectors using a
single table, but this will require reworking the linker script to split
the two into separate sections, so for now we have separate tables.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-15-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: template the entry asm functions
Mark Rutland [Mon, 7 Jun 2021 09:46:17 +0000 (10:46 +0100)]
arm64: entry: template the entry asm functions

Now that the majority of the exception triage logic has been converted
to C, the entry assembly functions all have a uniform structure.

Let's generate them all with an assembly macro to reduce the amount of
code and to ensure they all remain in sync if we make changes in future.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-14-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: improve bad_mode()
Mark Rutland [Mon, 7 Jun 2021 09:46:16 +0000 (10:46 +0100)]
arm64: entry: improve bad_mode()

Our use of bad_mode() has a few rough edges:

* AArch64 doesn't use the term "mode", and refers to "Execution
  states", "Exception levels", and "Selected stack pointer".

* We log the exception type (SYNC/IRQ/FIQ/SError), but not the actual
  "mode" (though this can be decoded from the SPSR value).

* We use bad_mode() as a second-level handler for unexpected synchronous
  exceptions, where the "mode" is legitimate, but the specific exception
  is not.

* We dump the ESR value, but call this "code", and so it's not clear to
  all readers that this is the ESR.

... and all of this can be somewhat opaque to those who aren't extremely
familiar with the code.

Let's make this a bit clearer by having bad_mode() log "Unhandled
${TYPE} exception" rather than "Bad mode in ${TYPE} handler", using
"ESR" rather than "code", and having the final panic() log "Unhandled
exception" rather than "Bad mode".

In future we'd like to log the specific architectural vector rather than
just the type of exception, so we also split the core of bad_mode() out
into a helper called __panic_unhandled(), which takes the vector as a
string argument.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-13-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: move bad_mode() to entry-common.c
Mark Rutland [Mon, 7 Jun 2021 09:46:15 +0000 (10:46 +0100)]
arm64: entry: move bad_mode() to entry-common.c

In subsequent patches we'll rework the way bad_mode() is called by
exception entry code. In preparation for this, let's move bad_mode()
itself into entry-common.c.

Let's also mark it as noinstr (e.g. to prevent it being kprobed), and
let's also make the `handler` array a local variable, as this is only
use by bad_mode(), and will be removed entirely in a subsequent patch.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-12-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: consolidate EL1 exception returns
Mark Rutland [Mon, 7 Jun 2021 09:46:14 +0000 (10:46 +0100)]
arm64: entry: consolidate EL1 exception returns

Following the example of ret_to_user, let's consolidate all the EL1
return paths with a ret_to_kernel helper, rather than each entry point
having its own copy of the return code.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-11-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: organise entry vectors consistently
Mark Rutland [Mon, 7 Jun 2021 09:46:13 +0000 (10:46 +0100)]
arm64: entry: organise entry vectors consistently

In subsequent patches we'll rename the entry handlers based on their
original EL, register width, and exception class. To do so, we need to
make all 3 mandatory arguments to the `kernel_ventry` macro, and
distinguish EL1h from EL1t.

In preparation for this, let's make the current set of arguments
mandatory, and move the `regsize` column before the branch label suffix,
making the vectors easier to read column-wise.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-10-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: organise entry handlers consistently
Mark Rutland [Mon, 7 Jun 2021 09:46:12 +0000 (10:46 +0100)]
arm64: entry: organise entry handlers consistently

In entry.S we have two comments which distinguish EL0 and EL1 exception
handlers, but the code isn't actually laid out to match, and there are a
few other inconsistencies that would be good to clear up.

This patch organizes the entry handers consistently:

* The handlers are laid out in order of the vectors, to make them easier
  to navigate.

* The inconsistently-applied alignment is removed

* The handlers are consistently marked with SYM_CODE_START_LOCAL()
  rather than SYM_CODE_START_LOCAL_NOALIGN(), giving them the same
  default alignment as other assembly code snippets.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-9-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: convert IRQ+FIQ handlers to C
Mark Rutland [Mon, 7 Jun 2021 09:46:11 +0000 (10:46 +0100)]
arm64: entry: convert IRQ+FIQ handlers to C

For various reasons we'd like to convert the bulk of arm64's exception
triage logic to C. As a step towards that, this patch converts the EL1
and EL0 IRQ+FIQ triage logic to C.

Separate C functions are added for the native and compat cases so that
in subsequent patches we can handle native/compat differences in C.

Since the triage functions can now call arm64_apply_bp_hardening()
directly, the do_el0_irq_bp_hardening() wrapper function is removed.

Since the user_exit_irqoff macro is now unused, it is removed. The
user_enter_irqoff macro is still used by the ret_to_user code, and
cannot be removed at this time.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-8-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: add a call_on_irq_stack helper
Mark Rutland [Mon, 7 Jun 2021 09:46:10 +0000 (10:46 +0100)]
arm64: entry: add a call_on_irq_stack helper

When handling IRQ/FIQ exceptions the entry assembly may transition from
a task's stack to a CPU's IRQ stack (and IRQ shadow call stack).

In subsequent patches we want to migrate the IRQ/FIQ triage logic to C,
and as we want to perform some actions on the task stack (e.g. EL1
preemption), we need to switch stacks within the C handler. So that we
can do so, this patch adds a helper to call a function on a CPU's IRQ
stack (and shadow stack as appropriate).

Subsequent patches will make use of the new helper function.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-7-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: move NMI preempt logic to C
Mark Rutland [Mon, 7 Jun 2021 09:46:09 +0000 (10:46 +0100)]
arm64: entry: move NMI preempt logic to C

Currently portions of our preempt logic are written in C while other
parts are written in assembly. Let's clean this up a little bit by
moving the NMI preempt checks to C. For now, the preempt count (and
need_resched) checking is left in assembly, and will be converted
with the body of the IRQ handler in subsequent patches.

Other than the increased lockdep coverage there should be no functional
change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-6-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: move arm64_preempt_schedule_irq to entry-common.c
Mark Rutland [Mon, 7 Jun 2021 09:46:08 +0000 (10:46 +0100)]
arm64: entry: move arm64_preempt_schedule_irq to entry-common.c

Subsequent patches will pull more of the IRQ entry handling into C. To
keep this in one place, let's move arm64_preempt_schedule_irq() into
entry-common.c along with the other entry management functions.

We no longer need to include <linux/lockdep.h> in process.c, so the
include directive is removed.

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

Reviewed-by Joey Gouly <joey.gouly@arm.com>

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-5-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: convert SError handlers to C
Mark Rutland [Mon, 7 Jun 2021 09:46:07 +0000 (10:46 +0100)]
arm64: entry: convert SError handlers to C

For various reasons we'd like to convert the bulk of arm64's exception
triage logic to C. As a step towards that, this patch converts the EL1
and EL0 SError triage logic to C.

Separate C functions are added for the native and compat cases so that
in subsequent patches we can handle native/compat differences in C.

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

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-4-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: entry: unmask IRQ+FIQ after EL0 handling
Mark Rutland [Mon, 7 Jun 2021 09:46:06 +0000 (10:46 +0100)]
arm64: entry: unmask IRQ+FIQ after EL0 handling

For non-fatal exceptions taken from EL0, we expect that at some point
during exception handling it is possible to return to a regular process
context with all exceptions unmasked (e.g. as we do in
do_notify_resume()), and we generally aim to unmask exceptions wherever
possible.

While handling SError and debug exceptions from EL0, we need to leave
some exceptions masked during handling. Handling SError requires us to
mask SError (which also requires masking IRQ+FIQ), and handing debug
exceptions requires us to mask debug (which also requires masking
SError+IRQ+FIQ).

Once do_serror() or do_debug_exception() has returned, we no longer need
to mask exceptions, and can unmask them all, which is what we did prior
to commit:

  9034f6251572a474 ("arm64: Do not enable IRQs for ct_user_exit")

... where we had to mask IRQs as for context_tracking_user_exit()
expected IRQs to be masked.

Since then, we realised that our context tracking wasn't entirely
correct, and reworked the entry code to fix this. As of commit:

  23529049c6842382 ("arm64: entry: fix non-NMI user<->kernel transitions")

... we replaced the call to context_tracking_user_exit() with a call to
user_exit_irqoff() as part of enter_from_user_mode(), which occurs
earlier, before we run the body of the handler and unmask exceptions in
DAIF.

When we return to userspace, we go via ret_to_user(), which masks
exceptions in DAIF prior to calling user_enter_irqoff() as part of
exit_to_user_mode().

Thus, there's no longer a reason to leave IRQs or FIQs masked at the end
of the EL0 debug or error handlers, as neither the user exit context
tracking nor the user entry context tracking requires this. Let's bring
these into line with other EL0 exception handlers and ensure that IRQ
and FIQ are unmasked in DAIF at some point during the handler.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: remove redundant local_daif_mask() in bad_mode()
Mark Rutland [Mon, 7 Jun 2021 09:46:05 +0000 (10:46 +0100)]
arm64: remove redundant local_daif_mask() in bad_mode()

Upon taking an exception, the CPU sets all the DAIF bits. We never
clear any of these bits prior to calling bad_mode(), and bad_mode()
itself never clears any of these bits, so there's no need to call
local_daif_mask().

This patch removes the redundant call.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210607094624.34689-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agokasan: disable freed user page poisoning with HW tags
Peter Collingbourne [Wed, 2 Jun 2021 23:52:30 +0000 (16:52 -0700)]
kasan: disable freed user page poisoning with HW tags

Poisoning freed pages protects against kernel use-after-free. The
likelihood of such a bug involving kernel pages is significantly higher
than that for user pages. At the same time, poisoning freed pages can
impose a significant performance cost, which cannot always be justified
for user pages given the lower probability of finding a bug. Therefore,
disable freed user page poisoning when using HW tags. We identify
"user" pages via the flag set GFP_HIGHUSER_MOVABLE, which indicates
a strong likelihood of not being directly accessible to the kernel.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://linux-review.googlesource.com/id/I716846e2de8ef179f44e835770df7e6307be96c9
Link: https://lore.kernel.org/r/20210602235230.3928842-5-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mte: handle tags zeroing at page allocation time
Peter Collingbourne [Wed, 2 Jun 2021 23:52:29 +0000 (16:52 -0700)]
arm64: mte: handle tags zeroing at page allocation time

Currently, on an anonymous page fault, the kernel allocates a zeroed
page and maps it in user space. If the mapping is tagged (PROT_MTE),
set_pte_at() additionally clears the tags. It is, however, more
efficient to clear the tags at the same time as zeroing the data on
allocation. To avoid clearing the tags on any page (which may not be
mapped as tagged), only do this if the vma flags contain VM_MTE. This
requires introducing a new GFP flag that is used to determine whether
to clear the tags.

The DC GZVA instruction with a 0 top byte (and 0 tag) requires
top-byte-ignore. Set the TCR_EL1.{TBI1,TBID1} bits irrespective of
whether KASAN_HW is enabled.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Co-developed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://linux-review.googlesource.com/id/Id46dc94e30fe11474f7e54f5d65e7658dbdddb26
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20210602235230.3928842-4-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agokasan: use separate (un)poison implementation for integrated init
Peter Collingbourne [Wed, 2 Jun 2021 23:52:28 +0000 (16:52 -0700)]
kasan: use separate (un)poison implementation for integrated init

Currently with integrated init page_alloc.c needs to know whether
kasan_alloc_pages() will zero initialize memory, but this will start
becoming more complicated once we start adding tag initialization
support for user pages. To avoid page_alloc.c needing to know more
details of what integrated init will do, move the unpoisoning logic
for integrated init into the HW tags implementation. Currently the
logic is identical but it will diverge in subsequent patches.

For symmetry do the same for poisoning although this logic will
be unaffected by subsequent patches.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://linux-review.googlesource.com/id/I2c550234c6c4a893c48c18ff0c6ce658c7c67056
Link: https://lore.kernel.org/r/20210602235230.3928842-3-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agomm: arch: remove indirection level in alloc_zeroed_user_highpage_movable()
Peter Collingbourne [Wed, 2 Jun 2021 23:52:27 +0000 (16:52 -0700)]
mm: arch: remove indirection level in alloc_zeroed_user_highpage_movable()

In an upcoming change we would like to add a flag to
GFP_HIGHUSER_MOVABLE so that it would no longer be an OR
of GFP_HIGHUSER and __GFP_MOVABLE. This poses a problem for
alloc_zeroed_user_highpage_movable() which passes __GFP_MOVABLE
into an arch-specific __alloc_zeroed_user_highpage() hook which ORs
in GFP_HIGHUSER.

Since __alloc_zeroed_user_highpage() is only ever called from
alloc_zeroed_user_highpage_movable(), we can remove one level
of indirection here. Remove __alloc_zeroed_user_highpage(),
make alloc_zeroed_user_highpage_movable() the hook, and use
GFP_HIGHUSER_MOVABLE in the hook implementations so that they will
pick up the new flag that we are going to add.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Link: https://linux-review.googlesource.com/id/Ic6361c657b2cdcd896adbe0cf7cb5a7fbb1ed7bf
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210602235230.3928842-2-pcc@google.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agodrivers/perf: hisi: Fix data source control
Shaokun Zhang [Thu, 3 Jun 2021 08:34:51 +0000 (16:34 +0800)]
drivers/perf: hisi: Fix data source control

'Data source' is a new function for HHA PMU and config / clear
interface was wrong by mistake. 'HHA_DATSRC_CTRL' register is
mainly used for data source configuration, if we enable bit0
as driver, it will go on count the event and we didn't check
it carefully. So fix the issue and do as the initial purpose.

Fixes: 932f6a99f9b0 ("drivers/perf: hisi: Add new functions for HHA PMU")
Reported-by: kernel test robot <lkp@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1622709291-37996-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: Add is_el1_data_abort() helper
Kefeng Wang [Thu, 3 Jun 2021 12:02:39 +0000 (20:02 +0800)]
arm64: mm: Add is_el1_data_abort() helper

We alread have is_el1_instruction_abort(), add is_el1_data_abort()
helper and use it.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210603120239.169018-1-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: perf: Add more support on caps under sysfs
Shaokun Zhang [Thu, 3 Jun 2021 07:15:02 +0000 (15:15 +0800)]
arm64: perf: Add more support on caps under sysfs

Armv8.7 has introduced BUS_SLOTS and BUS_WIDTH in PMMIR_EL1 register,
add two entries in caps for bus_slots and bus_width under sysfs. It
will return the true slots and width if the information is available,
otherwise it will return 0.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/1622704502-63951-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: update string routine copyrights and URLs
Mark Rutland [Wed, 2 Jun 2021 15:13:58 +0000 (16:13 +0100)]
arm64: update string routine copyrights and URLs

To make future archaeology easier, let's have the string routine comment
blocks encode the specific upstream commit ID they were imported from.
These are the same commit IDs as listed in the commits importing the
code, expanded to 16 characters. Note that the routines have different
commit IDs, each reprsenting the latest upstream commit which changed
the particular routine.

At the same time, let's consistently include 2021 in the copyright
dates.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210602151358.35571-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf: qcom_l2_pmu: move to use request_irq by IRQF_NO_AUTOEN flag
Tian Tao [Wed, 2 Jun 2021 01:00:42 +0000 (09:00 +0800)]
perf: qcom_l2_pmu: move to use request_irq by IRQF_NO_AUTOEN flag

request_irq() after setting IRQ_NOAUTOEN as below
irq_set_status_flags(irq, IRQ_NOAUTOEN); request_irq(dev, irq...); can
be replaced by request_irq() with IRQF_NO_AUTOEN flag.

this patch is made base on "add IRQF_NO_AUTOEN for request_irq" which
is being merged: https://lore.kernel.org/patchwork/patch/1388765/

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1622595642-61678-3-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm_pmu: move to use request_irq by IRQF_NO_AUTOEN flag
Tian Tao [Wed, 2 Jun 2021 01:00:41 +0000 (09:00 +0800)]
arm_pmu: move to use request_irq by IRQF_NO_AUTOEN flag

request_irq() after setting IRQ_NOAUTOEN as below
irq_set_status_flags(irq, IRQ_NOAUTOEN);
request_irq(dev, irq...);
can be replaced by request_irq() with IRQF_NO_AUTOEN flag.

this patch is made base on "add IRQF_NO_AUTOEN for request_irq" which
is being merged: https://lore.kernel.org/patchwork/patch/1388765/

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1622595642-61678-2-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)
Will Deacon [Thu, 27 May 2021 12:43:56 +0000 (13:43 +0100)]
arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)

Back in 97303480753e ("arm64: Increase the max granular size"),
ARCH_DMA_MINALIGN was effectively increased to 128 bytes thanks to an
increase in L1_CACHE_BYTES due to an unsubstantiated performance claim
on the now obsolete ThunderX-1. Although this was reverted in
d93277b9839b, ARCH_DMA_MINALIGN was kept at 128 bytes by ebc7e21e0fa2
("arm64: Increase ARCH_DMA_MINALIGN to 128").

During discussion of the original patch, it was reported that the change
also prevented a warning during boot on (again, now obsolete) Qualcomm
server hardware where the cache writeback granule was larger than 64
bytes. The reason for this warning was because non-coherent DMA could
lead to data corruption due to unexpected writeback from the CPU where a
cacheline is shared with other allocations.

Since then, systems have appeared with larger cachelines still, and so
commit 8f5c9037a55b ("arm64/mm: Correct the cache line size warning with
non coherent device") reworked the warning so that it only appears on
systems where non-coherent DMA is actually required and taints the
kernel with TAINT_CPU_OUT_OF_SPEC. We are not aware of any systems, even
including the aforementioned obsolete machines, which have a CWG larger
than 64 bytes and require non-coherent DMA.

More recently, it has been reported that a ARCH_DMA_MINALIGN of 128
bytes wastes considerable memory (~6% immediately after boot on one
system).

Reduce ARCH_DMA_MINALIGN to 64 bytes and allow the warning/taint to
indicate if there are machines that unknowingly rely on this.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Link: https://lore.kernel.org/linux-arm-kernel/1442944788-17254-1-git-send-email-rric@kernel.org/
Link: https://lore.kernel.org/linux-arm-kernel/CAOZdJXUiRMAguDV+HEJqPg57MyBNqEcTyaH+ya=U93NHb-pdJA@mail.gmail.com/
Link: https://lore.kernel.org/linux-arm-kernel/20190614131141.4428-1-msys.mizuma@gmail.com/
Link: https://lore.kernel.org/r/20210517074332.28280-1-vincent.whitchurch@axis.com
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210527124356.22367-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: Remove unused support for Normal-WT memory type
Will Deacon [Thu, 27 May 2021 11:03:19 +0000 (12:03 +0100)]
arm64: mm: Remove unused support for Normal-WT memory type

The Normal-WT memory type is unused, so remove it and reclaim a MAIR.

Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210527110319.22157-4-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: acpi: Map EFI_MEMORY_WT memory as Normal-NC
Will Deacon [Thu, 27 May 2021 11:03:18 +0000 (12:03 +0100)]
arm64: acpi: Map EFI_MEMORY_WT memory as Normal-NC

The only user we have of Normal Write-Through memory is in the ACPI code
when mapping memory regions advertised as EFI_MEMORY_WT. Since most (all?)
CPUs treat write-through as non-cacheable under the hood, don't bother
with the extra memory type here and just treat EFI_MEMORY_WT the same way
as EFI_MEMORY_WC by mapping it to the Normal-NC memory type instead and
emitting a warning if we have failed to find an alternative EFI memory
type.

Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20210527110319.22157-3-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: Remove unused support for Device-GRE memory type
Will Deacon [Thu, 27 May 2021 11:03:17 +0000 (12:03 +0100)]
arm64: mm: Remove unused support for Device-GRE memory type

The Device-GRE memory type is unused, so remove it and reclaim a MAIR.

Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210505180228.GA3874@arm.com
Link: https://lore.kernel.org/r/20210527110319.22157-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: mm: Use better bitmap_zalloc()
Kefeng Wang [Sat, 29 May 2021 11:15:10 +0000 (19:15 +0800)]
arm64: mm: Use better bitmap_zalloc()

Use better bitmap_zalloc() to allocate bitmap.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Link: https://lore.kernel.org/r/20210529111510.186355-1-wangkefeng.wang@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Rewrite __arch_clear_user()
Robin Murphy [Thu, 27 May 2021 15:34:48 +0000 (16:34 +0100)]
arm64: Rewrite __arch_clear_user()

Now that we're always using STTR variants rather than abstracting two
different addressing modes, the user_ldst macro here is frankly more
obfuscating than helpful. Rewrite __arch_clear_user() with regular
USER() annotations so that it's clearer what's going on, and take the
opportunity to minimise the branchiness in the most common paths, while
also allowing the exception fixup to return an accurate result.

Apparently some folks examine large reads from /dev/zero closely enough
to notice the loop being hot, so align it per the other critical loops
(presumably around a typical instruction fetch granularity).

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/1cbd78b12c076a8ad4656a345811cfb9425df0b3.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Better optimised memchr()
Robin Murphy [Thu, 27 May 2021 15:34:47 +0000 (16:34 +0100)]
arm64: Better optimised memchr()

Although we implement our own assembly version of memchr(), it turns
out to be barely any better than what GCC can generate for the generic
C version (and would go wrong if the size_t argument were ever large
enough to be interpreted as negative). Unfortunately we can't import the
tuned implementation from the Arm optimized-routines library, since that
has some Advanced SIMD parts which are not really viable for general
kernel library code. What we can do, however, is pep things up with some
relatively straightforward word-at-a-time logic for larger calls.

Adding some timing to optimized-routines' memchr() test for a simple
benchmark, overall this version comes in around half as fast as the SIMD
code, but still nearly 4x faster than our existing implementation.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/58471b42f9287e039dafa9e5e7035077152438fd.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Import latest memcpy()/memmove() implementation
Robin Murphy [Thu, 27 May 2021 15:34:46 +0000 (16:34 +0100)]
arm64: Import latest memcpy()/memmove() implementation

Import the latest implementation of memcpy(), based on the
upstream code of string/aarch64/memcpy.S at commit afd6244 from
https://github.com/ARM-software/optimized-routines, and subsuming
memmove() in the process.

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Note also that the needs of the usercopy routines vs. regular memcpy()
have now diverged so far that we abandon the shared template idea
and the damage which that incurred to the tuning of LDP/STP loops.
We'll be back to tackle those routines separately in future.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/3c953af43506581b2422f61952261e76949ba711.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Add assembly annotations for weak-PI-alias madness
Robin Murphy [Thu, 27 May 2021 15:34:45 +0000 (16:34 +0100)]
arm64: Add assembly annotations for weak-PI-alias madness

Add yet another set of assembly symbol annotations, this time for the
borderline-absurd situation of a function aliasing to a weak symbol
which itself also wants a position-independent alias.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/75545b3c4129b20b887474bb58a9cf302bf2132b.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Import latest version of Cortex Strings' strncmp
Sam Tebbs [Thu, 27 May 2021 15:34:44 +0000 (16:34 +0100)]
arm64: Import latest version of Cortex Strings' strncmp

Import the latest version of the former Cortex Strings - now
Arm Optimized Routines - strncmp function based on the upstream
code of string/aarch64/strncmp.S at commit e823e3a from
https://github.com/ARM-software/optimized-routines

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Signed-off-by: Sam Tebbs <sam.tebbs@arm.com>
[ rm: update attribution and commit message ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/26110bee02ad360596c9a7536af7eaaf6890d0e8.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Import updated version of Cortex Strings' strlen
Sam Tebbs [Thu, 27 May 2021 15:34:43 +0000 (16:34 +0100)]
arm64: Import updated version of Cortex Strings' strlen

Import an updated version of the former Cortex Strings - now Arm
Optimized Routines - strcmp function. The latest version introduces
Advanced SIMD usage which rules it out for our purposes, but we can
still pick an intermediate improvement from the previous version,
namely string/aarch64/strlen.S at commit 98e4d6a from
https://github.com/ARM-software/optimized-routines

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Signed-off-by: Sam Tebbs <sam.tebbs@arm.com>
[ rm: update attribution and commit message ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/32e3489398a24b23ae6e996935ac4818f8fd9dfd.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Import latest version of Cortex Strings' strcmp
Sam Tebbs [Thu, 27 May 2021 15:34:42 +0000 (16:34 +0100)]
arm64: Import latest version of Cortex Strings' strcmp

Import the latest version of the former Cortex Strings - now
Arm Optimized Routines - strcmp function based on the upstream
code of string/aarch64/strcmp.S at commit afd6244 from
https://github.com/ARM-software/optimized-routines

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Signed-off-by: Sam Tebbs <sam.tebbs@arm.com>
[ rm: update attribution and commit message ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/0fe90c90b96b569fbdfd46e47bd1298abb02079e.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoarm64: Import latest version of Cortex Strings' memcmp
Sam Tebbs [Thu, 27 May 2021 15:34:41 +0000 (16:34 +0100)]
arm64: Import latest version of Cortex Strings' memcmp

Import the latest version of the former Cortex Strings - now
Arm Optimized Routines - memcmp function based on the upstream
code of string/aarch64/memcmp.S at commit e823e3a from
https://github.com/ARM-software/optimized-routines

Note that for simplicity Arm have chosen to contribute this code
to Linux under GPLv2 rather than the original MIT license.

Signed-off-by: Sam Tebbs <sam.tebbs@arm.com>
[ rm: update attribution and commit message ]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/2889de2d41054f3f508fb3addad784a3606ef383.1622128527.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
3 years agoperf: arm_spe: use DEVICE_ATTR_RO macro
YueHaibing [Fri, 28 May 2021 06:17:38 +0000 (14:17 +0800)]
perf: arm_spe: use DEVICE_ATTR_RO macro

Use DEVICE_ATTR_RO() helper instead of plain DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20210528061738.23392-1-yuehaibing@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>