On a randomly chosen distro kernel build for arm64, vmlinux.o shows the
following sections, containing jump label entries, and the associated
RELA relocation records, respectively:
...
[38088] __jump_table PROGBITS 0000000000000000 00e19f30
000000000002ea10 0000000000000000 WA 0 0 8
[38089] .rela__jump_table RELA 0000000000000000 01fd8bb0
000000000008be30 0000000000000018 I 38178 38088 8
...
In other words, we have 190 KB worth of 'struct jump_entry' instances,
and 573 KB worth of RELA entries to relocate each entry's code, target
and key members. This means the RELA section occupies 10% of the .init
segment, and the two sections combined represent 5% of vmlinux's entire
memory footprint.
So let's switch from 64-bit absolute references to 32-bit relative
references for the code and target field, and a 64-bit relative
reference for the 'key' field (which may reside in another module or the
core kernel, which may be more than 4 GB way on arm64 when running with
KASLR enable): this reduces the size of the __jump_table by 33%, and
gets rid of the RELA section entirely.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Link: https://lkml.kernel.org/r/20180919065144.25010-4-ard.biesheuvel@linaro.org
All other uses of "asm goto" go through asm_volatile_goto, which avoids
a miscompile when using GCC < 4.8.2. Replace our open-coded "asm goto"
statements with the asm_volatile_goto macro to avoid issues with older
toolchains.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The lock has never been used and the page tables are protected by
mmu_lock in struct kvm.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
kvm_unmap_hva is long gone, and we only have kvm_unmap_hva_range to
deal with. Drop the now obsolete code.
Fixes: fb1522e099 ("KVM: update to new mmu_notifier semantic v2")
Cc: James Hogan <jhogan@kernel.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
As of commit fd1102f0aa ("mm: mmu_notifier fix for tlb_end_vma"),
asm-generic/tlb.h now calls tlb_flush() from a static inline function,
so we need to make sure that it's declared before #including the
asm-generic header in the arch header.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Support for Group0 interrupts in guests
- Cache management optimizations for ARMv8.4 systems
- Userspace interface for RAS, allowing error retrival and injection
- Fault path optimization
- Emulated physical timer fixes
- Random cleanups
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Merge tag 'kvmarm-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm updates for 4.19
- Support for Group0 interrupts in guests
- Cache management optimizations for ARMv8.4 systems
- Userspace interface for RAS, allowing error retrival and injection
- Fault path optimization
- Emulated physical timer fixes
- Random cleanups
A bunch of good stuff in here:
- Wire up support for qspinlock, replacing our trusty ticket lock code
- Add an IPI to flush_icache_range() to ensure that stale instructions
fetched into the pipeline are discarded along with the I-cache lines
- Support for the GCC "stackleak" plugin
- Support for restartable sequences, plus an arm64 port for the selftest
- Kexec/kdump support on systems booting with ACPI
- Rewrite of our syscall entry code in C, which allows us to zero the
GPRs on entry from userspace
- Support for chained PMU counters, allowing 64-bit event counters to be
constructed on current CPUs
- Ensure scheduler topology information is kept up-to-date with CPU
hotplug events
- Re-enable support for huge vmalloc/IO mappings now that the core code
has the correct hooks to use break-before-make sequences
- Miscellaneous, non-critical fixes and cleanups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"A bunch of good stuff in here. Worth noting is that we've pulled in
the x86/mm branch from -tip so that we can make use of the core
ioremap changes which allow us to put down huge mappings in the
vmalloc area without screwing up the TLB. Much of the positive
diffstat is because of the rseq selftest for arm64.
Summary:
- Wire up support for qspinlock, replacing our trusty ticket lock
code
- Add an IPI to flush_icache_range() to ensure that stale
instructions fetched into the pipeline are discarded along with the
I-cache lines
- Support for the GCC "stackleak" plugin
- Support for restartable sequences, plus an arm64 port for the
selftest
- Kexec/kdump support on systems booting with ACPI
- Rewrite of our syscall entry code in C, which allows us to zero the
GPRs on entry from userspace
- Support for chained PMU counters, allowing 64-bit event counters to
be constructed on current CPUs
- Ensure scheduler topology information is kept up-to-date with CPU
hotplug events
- Re-enable support for huge vmalloc/IO mappings now that the core
code has the correct hooks to use break-before-make sequences
- Miscellaneous, non-critical fixes and cleanups"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (90 commits)
arm64: alternative: Use true and false for boolean values
arm64: kexec: Add comment to explain use of __flush_icache_range()
arm64: sdei: Mark sdei stack helper functions as static
arm64, kaslr: export offset in VMCOREINFO ELF notes
arm64: perf: Add cap_user_time aarch64
efi/libstub: Only disable stackleak plugin for arm64
arm64: drop unused kernel_neon_begin_partial() macro
arm64: kexec: machine_kexec should call __flush_icache_range
arm64: svc: Ensure hardirq tracing is updated before return
arm64: mm: Export __sync_icache_dcache() for xen-privcmd
drivers/perf: arm-ccn: Use devm_ioremap_resource() to map memory
arm64: Add support for STACKLEAK gcc plugin
arm64: Add stack information to on_accessible_stack
drivers/perf: hisi: update the sccl_id/ccl_id when MT is supported
arm64: fix ACPI dependencies
rseq/selftests: Add support for arm64
arm64: acpi: fix alignment fault in accessing ACPI
efi/arm: map UEFI memory map even w/o runtime services enabled
efi/arm: preserve early mapping of UEFI memory map longer for BGRT
drivers: acpi: add dependency of EFI for arm64
...
Pull perf update from Thomas Gleixner:
"The perf crowd presents:
Kernel updates:
- Removal of jprobes
- Cleanup and consolidatation the handling of kprobes
- Cleanup and consolidation of hardware breakpoints
- The usual pile of fixes and updates to PMUs and event descriptors
Tooling updates:
- Updates and improvements all over the place. Nothing outstanding,
just the (good) boring incremental grump work"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
perf trace: Do not require --no-syscalls to suppress strace like output
perf bpf: Include uapi/linux/bpf.h from the 'perf trace' script's bpf.h
perf tools: Allow overriding MAX_NR_CPUS at compile time
perf bpf: Show better message when failing to load an object
perf list: Unify metric group description format with PMU event description
perf vendor events arm64: Update ThunderX2 implementation defined pmu core events
perf cs-etm: Generate branch sample for CS_ETM_TRACE_ON packet
perf cs-etm: Generate branch sample when receiving a CS_ETM_TRACE_ON packet
perf cs-etm: Support dummy address value for CS_ETM_TRACE_ON packet
perf cs-etm: Fix start tracing packet handling
perf build: Fix installation directory for eBPF
perf c2c report: Fix crash for empty browser
perf tests: Fix indexing when invoking subtests
perf trace: Beautify the AF_INET & AF_INET6 'socket' syscall 'protocol' args
perf trace beauty: Add beautifiers for 'socket''s 'protocol' arg
perf trace beauty: Do not print NULL strarray entries
perf beauty: Add a generator for IPPROTO_ socket's protocol constants
tools include uapi: Grab a copy of linux/in.h
perf tests: Fix complex event name parsing
perf evlist: Fix error out while applying initial delay and LBR
...
Pull locking/atomics update from Thomas Gleixner:
"The locking, atomics and memory model brains delivered:
- A larger update to the atomics code which reworks the ordering
barriers, consolidates the atomic primitives, provides the new
atomic64_fetch_add_unless() primitive and cleans up the include
hell.
- Simplify cmpxchg() instrumentation and add instrumentation for
xchg() and cmpxchg_double().
- Updates to the memory model and documentation"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
locking/atomics: Rework ordering barriers
locking/atomics: Instrument cmpxchg_double*()
locking/atomics: Instrument xchg()
locking/atomics: Simplify cmpxchg() instrumentation
locking/atomics/x86: Reduce arch_cmpxchg64*() instrumentation
tools/memory-model: Rename litmus tests to comply to norm7
tools/memory-model/Documentation: Fix typo, smb->smp
sched/Documentation: Update wake_up() & co. memory-barrier guarantees
locking/spinlock, sched/core: Clarify requirements for smp_mb__after_spinlock()
sched/core: Use smp_mb() in wake_woken_function()
tools/memory-model: Add informal LKMM documentation to MAINTAINERS
locking/atomics/Documentation: Describe atomic_set() as a write operation
tools/memory-model: Make scripts executable
tools/memory-model: Remove ACCESS_ONCE() from model
tools/memory-model: Remove ACCESS_ONCE() from recipes
locking/memory-barriers.txt/kokr: Update Korean translation to fix broken DMA vs. MMIO ordering example
MAINTAINERS: Add Daniel Lustig as an LKMM reviewer
tools/memory-model: Fix ISA2+pooncelock+pooncelock+pombonce name
tools/memory-model: Add litmus test for full multicopy atomicity
locking/refcount: Always allow checked forms
...
Pull genirq updates from Thomas Gleixner:
"The irq departement provides:
- A synchronization fix for free_irq() to synchronize just the
removed interrupt thread on shared interrupt lines.
- Consolidate the multi low level interrupt entry handling and mvoe
it to the generic code instead of adding yet another copy for
RISC-V
- Refactoring of the ARM LPI allocator and LPI exposure to the
hypervisor
- Yet another interrupt chip driver for the JZ4725B SoC
- Speed up for /proc/interrupts as people seem to love reading this
file with high frequency
- Miscellaneous fixes and updates"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
irqchip/gic-v3-its: Make its_lock a raw_spin_lock_t
genirq/irqchip: Remove MULTI_IRQ_HANDLER as it's now obselete
openrisc: Use the new GENERIC_IRQ_MULTI_HANDLER
arm64: Use the new GENERIC_IRQ_MULTI_HANDLER
ARM: Convert to GENERIC_IRQ_MULTI_HANDLER
irqchip: Port the ARM IRQ drivers to GENERIC_IRQ_MULTI_HANDLER
irqchip/gic-v3-its: Reduce minimum LPI allocation to 1 for PCI devices
dt-bindings: irqchip: renesas-irqc: Document r8a77980 support
dt-bindings: irqchip: renesas-irqc: Document r8a77470 support
irqchip/ingenic: Add support for the JZ4725B SoC
irqchip/stm32: Add exti0 translation for stm32mp1
genirq: Remove redundant NULL pointer check in __free_irq()
irqchip/gic-v3-its: Honor hypervisor enforced LPI range
irqchip/gic-v3: Expose GICD_TYPER in the rdist structure
irqchip/gic-v3-its: Drop chunk allocation compatibility
irqchip/gic-v3-its: Move minimum LPI requirements to individual busses
irqchip/gic-v3-its: Use full range of LPIs
irqchip/gic-v3-its: Refactor LPI allocator
genirq: Synchronize only with single thread on free_irq()
genirq: Update code comments wrt recycled thread_mask
...
Pull EFI updates from Thomas Gleixner:
"The EFI pile:
- Make mixed mode UEFI runtime service invocations mutually
exclusive, as mandated by the UEFI spec
- Perform UEFI runtime services calls from a work queue so the calls
into the firmware occur from a kernel thread
- Honor the UEFI memory map attributes for live memory regions
configured by UEFI as a framebuffer. This works around a coherency
problem with KVM guests running on ARM.
- Cleanups, improvements and fixes all over the place"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efivars: Call guid_parse() against guid_t type of variable
efi/cper: Use consistent types for UUIDs
efi/x86: Replace references to efi_early->is64 with efi_is_64bit()
efi: Deduplicate efi_open_volume()
efi/x86: Add missing NULL initialization in UGA draw protocol discovery
efi/x86: Merge 32-bit and 64-bit UGA draw protocol setup routines
efi/x86: Align efi_uga_draw_protocol typedef names to convention
efi/x86: Merge the setup_efi_pci32() and setup_efi_pci64() routines
efi/x86: Prevent reentrant firmware calls in mixed mode
efi/esrt: Only call efi_mem_reserve() for boot services memory
fbdev/efifb: Honour UEFI memory map attributes when mapping the FB
efi: Drop type and attribute checks in efi_mem_desc_lookup()
efi/libstub/arm: Add opt-in Kconfig option for the DTB loader
efi: Remove the declaration of efi_late_init() as the function is unused
efi/cper: Avoid using get_seconds()
efi: Use a work queue to invoke EFI Runtime Services
efi/x86: Use non-blocking SetVariable() for efi_delete_dummy_variable()
efi/x86: Clean up the eboot code
In order to generate Group0 SGIs, let's add some decoding logic to
access_gic_sgi(), and pass the generating group accordingly.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
- GICv3 ITS LPI allocation revamp
- GICv3 support for hypervisor-enforced LPI range
- GICv3 ITS conversion to raw spinlock
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Merge tag 'irqchip-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- GICv3 ITS LPI allocation revamp
- GICv3 support for hypervisor-enforced LPI range
- GICv3 ITS conversion to raw spinlock
Commit 2c4541e24c ("mm: use vma_init() to initialize VMAs on stack and
data segments") tried to initialize various left-over ad-hoc vma's
"properly", but actually made things worse for the temporary vma's used
for TLB flushing.
vma_init() doesn't actually initialize all of the vma, just a few
fields, so doing something like
- struct vm_area_struct vma = { .vm_mm = tlb->mm, };
+ struct vm_area_struct vma;
+
+ vma_init(&vma, tlb->mm);
was actually very bad: instead of having a nicely initialized vma with
every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
with only a couple of fields initialized. And they weren't even fields
that the code in question mostly cared about.
The flush_tlb_range() function takes a "struct vma" rather than a
"struct mm_struct", because a few architectures actually care about what
kind of range it is - being able to only do an ITLB flush if it's a
range that doesn't have data accesses enabled, for example. And all the
normal users already have the vma for doing the range invalidation.
But a few people want to call flush_tlb_range() with a range they just
made up, so they also end up using a made-up vma. x86 just has a
special "flush_tlb_mm_range()" function for this, but other
architectures (arm and ia64) do the "use fake vma" thing instead, and
thus got caught up in the vma_init() changes.
At the same time, the TLB flushing code really doesn't care about most
other fields in the vma, so vma_init() is just unnecessary and
pointless.
This fixes things by having an explicit "this is just an initializer for
the TLB flush" initializer macro, which is used by the arm/arm64/ia64
people who mis-use this interface with just a dummy vma.
Fixes: 2c4541e24c ("mm: use vma_init() to initialize VMAs on stack and data segments")
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When kernel mode NEON was first introduced to the arm64 kernel,
every call to kernel_neon_begin()/_end() stacked resp. unstacked
the entire NEON register file, making it worthwile to reduce the
number of used NEON registers to a bare minimum, and only stack
those. kernel_neon_begin_partial() was introduced for this purpose,
but after the refactoring for SVE and other changes, it no longer
exists and was simply #define'd to kernel_neon_begin() directly.
In the mean time, all users have been updated, so let's remove
the fallback macro.
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Make sure to initialize all VMAs properly, not only those which come
from vm_area_cachep.
Link: http://lkml.kernel.org/r/20180724121139.62570-3-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds support for the STACKLEAK gcc plugin to arm64 by implementing
stackleak_check_alloca(), based heavily on the x86 version, and adding the
two helpers used by the stackleak common code: current_top_of_stack() and
on_thread_stack(). The stack erasure calls are made at syscall returns.
Additionally, this disables the plugin in hypervisor and EFI stub code,
which are out of scope for the protection.
Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation for enabling the stackleak plugin on arm64,
we need a way to get the bounds of the current stack. Extend
on_accessible_stack to get this information.
Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
[will: folded in fix for allmodconfig build breakage w/ sdei]
Signed-off-by: Will Deacon <will.deacon@arm.com>
This is a fix against the issue that crash dump kernel may hang up
during booting, which can happen on any ACPI-based system with "ACPI
Reclaim Memory."
(kernel messages after panic kicked off kdump)
(snip...)
Bye!
(snip...)
ACPI: Core revision 20170728
pud=000000002e7d0003, *pmd=000000002e7c0003, *pte=00e8000039710707
Internal error: Oops: 96000021 [#1] SMP
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.14.0-rc6 #1
task: ffff000008d05180 task.stack: ffff000008cc0000
PC is at acpi_ns_lookup+0x25c/0x3c0
LR is at acpi_ds_load1_begin_op+0xa4/0x294
(snip...)
Process swapper/0 (pid: 0, stack limit = 0xffff000008cc0000)
Call trace:
(snip...)
[<ffff0000084a6764>] acpi_ns_lookup+0x25c/0x3c0
[<ffff00000849b4f8>] acpi_ds_load1_begin_op+0xa4/0x294
[<ffff0000084ad4ac>] acpi_ps_build_named_op+0xc4/0x198
[<ffff0000084ad6cc>] acpi_ps_create_op+0x14c/0x270
[<ffff0000084acfa8>] acpi_ps_parse_loop+0x188/0x5c8
[<ffff0000084ae048>] acpi_ps_parse_aml+0xb0/0x2b8
[<ffff0000084a8e10>] acpi_ns_one_complete_parse+0x144/0x184
[<ffff0000084a8e98>] acpi_ns_parse_table+0x48/0x68
[<ffff0000084a82cc>] acpi_ns_load_table+0x4c/0xdc
[<ffff0000084b32f8>] acpi_tb_load_namespace+0xe4/0x264
[<ffff000008baf9b4>] acpi_load_tables+0x48/0xc0
[<ffff000008badc20>] acpi_early_init+0x9c/0xd0
[<ffff000008b70d50>] start_kernel+0x3b4/0x43c
Code: b9008fb9 2a000318 36380054 32190318 (b94002c0)
---[ end trace c46ed37f9651c58e ]---
Kernel panic - not syncing: Fatal exception
Rebooting in 10 seconds..
(diagnosis)
* This fault is a data abort, alignment fault (ESR=0x96000021)
during reading out ACPI table.
* Initial ACPI tables are normally stored in system ram and marked as
"ACPI Reclaim memory" by the firmware.
* After the commit f56ab9a5b7 ("efi/arm: Don't mark ACPI reclaim
memory as MEMBLOCK_NOMAP"), those regions are differently handled
as they are "memblock-reserved", without NOMAP bit.
* So they are now excluded from device tree's "usable-memory-range"
which kexec-tools determines based on a current view of /proc/iomem.
* When crash dump kernel boots up, it tries to accesses ACPI tables by
mapping them with ioremap(), not ioremap_cache(), in acpi_os_ioremap()
since they are no longer part of mapped system ram.
* Given that ACPI accessor/helper functions are compiled in without
unaligned access support (ACPI_MISALIGNMENT_NOT_SUPPORTED),
any unaligned access to ACPI tables can cause a fatal panic.
With this patch, acpi_os_ioremap() always honors memory attribute
information provided by the firmware (EFI) and retaining cacheability
allows the kernel safe access to ACPI tables.
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by and Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
There's one ARM, one x86_32 and one x86_64 version of efi_open_volume()
which can be folded into a single shared version by masking their
differences with the efi_call_proto() macro introduced by commit:
3552fdf29f ("efi: Allow bitness-agnostic protocol calls").
To be able to dereference the device_handle attribute from the
efi_loaded_image_t table in an arch- and bitness-agnostic manner,
introduce the efi_table_attr() macro (which already exists for x86)
to arm and arm64.
No functional change intended.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180720014726.24031-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The get/set events helpers to do some work to check reserved
and padding fields are zero. This is useful on 32bit too.
Move this code into virt/kvm/arm/arm.c, and give the arch
code some underscores.
This is temporarily hidden behind __KVM_HAVE_VCPU_EVENTS until
32bit is wired up.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Dongjiu Geng <gengdongjiu@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
For the migrating VMs, user space may need to know the exception
state. For example, in the machine A, KVM make an SError pending,
when migrate to B, KVM also needs to pend an SError.
This new IOCTL exports user-invisible states related to SError.
Together with appropriate user space changes, user space can get/set
the SError exception state to do migrate/snapshot/suspend.
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Reviewed-by: James Morse <james.morse@arm.com>
[expanded documentation wording]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
When running on a non-VHE system, we initialize tpidr_el2 to
contain the per-CPU offset required to reach per-cpu variables.
Actually, we initialize it twice: the first time as part of the
EL2 initialization, by copying tpidr_el1 into its el2 counterpart,
and another time by calling into __kvm_set_tpidr_el2.
It turns out that the first part is wrong, as it includes the
distance between the kernel mapping and the linear mapping, while
EL2 only cares about the linear mapping. This was the last vestige
of the first per-cpu use of tpidr_el2 that came in with SDEI.
The only caller then was hyp_panic(), and its now using the
pc-relative get_host_ctxt() stuff, instead of kimage addresses
from the literal pool.
It is not a big deal, as we override it straight away, but it is
slightly confusing. In order to clear said confusion, let's
set this directly as part of the hyp-init code, and drop the
ad-hoc HYP helper.
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
To minimize the risk of userspace-controlled values being used under
speculation, this patch adds pt_regs based syscall wrappers for arm64,
which pass the minimum set of required userspace values to syscall
implementations. For each syscall, a wrapper which takes a pt_regs
argument is automatically generated, and this extracts the arguments
before calling the "real" syscall implementation.
Each syscall has three functions generated:
* __do_<compat_>sys_<name> is the "real" syscall implementation, with
the expected prototype.
* __se_<compat_>sys_<name> is the sign-extension/narrowing wrapper,
inherited from common code. This takes a series of long parameters,
casting each to the requisite types required by the "real" syscall
implementation in __do_<compat_>sys_<name>.
This wrapper *may* not be necessary on arm64 given the AAPCS rules on
unused register bits, but it seemed safer to keep the wrapper for now.
* __arm64_<compat_>_sys_<name> takes a struct pt_regs pointer, and
extracts *only* the relevant register values, passing these on to the
__se_<compat_>sys_<name> wrapper.
The syscall invocation code is updated to handle the calling convention
required by __arm64_<compat_>_sys_<name>, and passes a single struct
pt_regs pointer.
The compiler can fold the syscall implementation and its wrappers, such
that the overhead of this approach is minimized.
Note that we play games with sys_ni_syscall(). It can't be defined with
SYSCALL_DEFINE0() because we must avoid the possibility of error
injection. Additionally, there are a couple of locations where we need
to call it from C code, and we don't (currently) have a
ksys_ni_syscall(). While it has no wrapper, passing in a redundant
pt_regs pointer is benign per the AAPCS.
When ARCH_HAS_SYSCALL_WRAPPER is selected, no prototype is defines for
sys_ni_syscall(). Since we need to treat it differently for in-kernel
calls and the syscall tables, the prototype is defined as-required.
The wrappers are largely the same as their x86 counterparts, but
simplified as we don't have a variety of compat calling conventions that
require separate stubs. Unlike x86, we have some zero-argument compat
syscalls, and must define COMPAT_SYSCALL_DEFINE0() to ensure that these
are also given an __arm64_compat_sys_ prefix.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation for converting to pt_regs syscall wrappers, convert our
existing compat wrappers to C. This will allow the pt_regs wrappers to
be automatically generated, and will allow for the compat register
manipulation to be folded in with the pt_regs accesses.
To avoid confusion with the upcoming pt_regs wrappers and existing
compat wrappers provided by core code, the C wrappers are renamed to
compat_sys_aarch32_<syscall>.
With the assembly wrappers gone, we can get rid of entry32.S and the
associated boilerplate.
Note that these must call the ksys_* syscall entry points, as the usual
sys_* entry points will be modified to take a single pt_regs pointer
argument.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that the syscall invocation logic is in C, we can migrate the rest
of the syscall entry logic over, so that the entry assembly needn't look
at the register values at all.
The SVE reset across syscall logic now unconditionally clears TIF_SVE,
but sve_user_disable() will only write back to CPACR_EL1 when SVE is
actually enabled.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation for invoking arbitrary syscalls from C code, let's define
a type for an arbitrary syscall, matching the parameter passing rules of
the AAPCS.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
The arm64 sigreturn* syscall handlers are non-standard. Rather than
taking a number of user parameters in registers as per the AAPCS,
they expect the pt_regs as their sole argument.
To make this work, we override the syscall definitions to invoke
wrappers written in assembly, which mov the SP into x0, and branch to
their respective C functions.
On other architectures (such as x86), the sigreturn* functions take no
argument and instead use current_pt_regs() to acquire the user
registers. This requires less boilerplate code, and allows for other
features such as interposing C code in this path.
This patch takes the same approach for arm64.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tentatively-reviewed-by: Dave Martin <dave.martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In subsequent patches, we'll want to make use of sve_user_enable() and
sve_user_disable() outside of kernel/fpsimd.c. Let's move these to
<asm/fpsimd.h> where we can make use of them.
To avoid ifdeffery in sequences like:
if (system_supports_sve() && some_condition)
sve_user_disable();
... empty stubs are provided when support for SVE is not enabled. Note
that system_supports_sve() contains as IS_ENABLED(CONFIG_ARM64_SVE), so
the sve_user_disable() call should be optimized away entirely when
CONFIG_ARM64_SVE is not selected.
To ensure that this is the case, the stub definitions contain a
BUILD_BUG(), as we do for other stubs for which calls should always be
optimized away when the relevant config option is not selected.
At the same time, the include list of <asm/fpsimd.h> is sorted while
adding <asm/sysreg.h>.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that we have sysreg_clear_set(), we can consistently use this
instead of config_sctlr_el1().
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Currently we assert that the SCTLR_EL{1,2}_{SET,CLEAR} bits are
self-consistent with an assertion in config_sctlr_el1(). This is a bit
unusual, since config_sctlr_el1() doesn't make use of these definitions,
and is far away from the definitions themselves.
We can use the CPP #error directive to have equivalent assertions in
<asm/sysreg.h>, next to the definitions of the set/clear bits, which is
a bit clearer and simpler.
At the same time, lets fill in the upper 32 bits for both registers in
their respective RES0 definitions. This could be a little nicer with
GENMASK_ULL(63, 32), but this currently lives in <linux/bitops.h>, which
cannot safely be included from assembly, as <asm/sysreg.h> can.
Note the when the preprocessor evaluates an expression for an #if
directive, all signed or unsigned values are treated as intmax_t or
uintmax_t respectively. To avoid ambiguity, we define explicitly define
the mask of all 64 bits.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
It does not matter if the caller of may_use_simd() migrates to
another cpu after the call, but it is still important that the
kernel_neon_busy percpu instance that is read matches the cpu the
task is running on at the time of the read.
This means that raw_cpu_read() is not sufficient. kernel_neon_busy
may appear true if the caller migrates during the execution of
raw_cpu_read() and the next task to be scheduled in on the initial
cpu calls kernel_neon_begin().
This patch replaces raw_cpu_read() with this_cpu_read() to protect
against this race.
Cc: <stable@vger.kernel.org>
Fixes: cb84d11e16 ("arm64: neon: Remove support for nested or hardirq kernel-mode NEON")
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Yandong Zhao <yandong77520@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Implement calls to rseq_signal_deliver, rseq_handle_notify_resume
and rseq_syscall so that we can select HAVE_RSEQ on arm64.
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Current ACPI ARM64 NUMA initialization code in
acpi_numa_gicc_affinity_init()
carries out NUMA nodes creation and cpu<->node mappings at the same time
in the arch backend so that a single SRAT walk is needed to parse both
pieces of information. This implies that the cpu<->node mappings must
be stashed in an array (sized NR_CPUS) so that SMP code can later use
the stashed values to avoid another SRAT table walk to set-up the early
cpu<->node mappings.
If the kernel is configured with a NR_CPUS value less than the actual
processor entries in the SRAT (and MADT), the logic in
acpi_numa_gicc_affinity_init() is broken in that the cpu<->node mapping
is only carried out (and stashed for future use) only for a number of
SRAT entries up to NR_CPUS, which do not necessarily correspond to the
possible cpus detected at SMP initialization in
acpi_map_gic_cpu_interface() (ie MADT and SRAT processor entries order
is not enforced), which leaves the kernel with broken cpu<->node
mappings.
Furthermore, given the current ACPI NUMA code parsing logic in
acpi_numa_gicc_affinity_init(), PXM domains for CPUs that are not parsed
because they exceed NR_CPUS entries are not mapped to NUMA nodes (ie the
PXM corresponding node is not created in the kernel) leaving the system
with a broken NUMA topology.
Rework the ACPI ARM64 NUMA initialization process so that the NUMA
nodes creation and cpu<->node mappings are decoupled. cpu<->node
mappings are moved to SMP initialization code (where they are needed),
at the cost of an extra SRAT walk so that ACPI NUMA mappings can be
batched before being applied, fixing current parsing pitfalls.
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: John Garry <john.garry@huawei.com>
Fixes: d8b47fca8c ("arm64, ACPI, NUMA: NUMA support based on SRAT and
SLIT")
Link: http://lkml.kernel.org/r/1527768879-88161-2-git-send-email-xiexiuqi@huawei.com
Reported-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
Cc: Jeremy Linton <jeremy.linton@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Trapping blocking WFE is extremely beneficial in situations where
the system is oversubscribed, as it allows another thread to run
while being blocked. In a non-oversubscribed environment, this is
the complete opposite, and trapping WFE is just unnecessary overhead.
Let's only enable WFE trapping if the CPU has more than a single task
to run (that is, more than just the vcpu thread).
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
The {pmd,pud,pgd}_populate accessors usage have always been a bit weird
in KVM. We don't have a struct mm to pass (and neither does the kernel
most of the time, but still...), and the 32bit code has all kind of
cache maintenance that doesn't make sense on ARMv7+ when MP extensions
are mandatory (which is the case when the VEs are present).
Let's bite the bullet and provide our own implementations. The only bit
of architectural code left has to do with building the table entry
itself (arm64 having up to 52bit PA, arm lacking PUD level).
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
The arm and arm64 KVM page tables accessors are pointlessly different
between the two architectures, and likely both wrong one way or another:
arm64 lacks a dsb(), and arm doesn't use WRITE_ONCE.
Let's unify them.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
On systems where CTR_EL0.DIC is set, we don't need to perform
icache invalidation to guarantee that we'll fetch the right
instruction stream.
This also means that taking a permission fault to invalidate the
icache is an unnecessary overhead.
On such systems, we can safely leave the page as being executable.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Up to ARMv8.3, the combinaison of Stage-1 and Stage-2 attributes
results in the strongest attribute of the two stages. This means
that the hypervisor has to perform quite a lot of cache maintenance
just in case the guest has some non-cacheable mappings around.
ARMv8.4 solves this problem by offering a different mode (FWB) where
Stage-2 has total control over the memory attribute (this is limited
to systems where both I/O and instruction fetches are coherent with
the dcache). This is achieved by having a different set of memory
attributes in the page tables, and a new bit set in HCR_EL2.
On such a system, we can then safely sidestep any form of dcache
management.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Similar to core_sibling and thread_sibling, it's better to align and
rename llc_siblings to llc_sibling.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch adds support to remove all the CPU topology information using
clear_cpu_topology and also resetting the sibling information on other
sibling CPUs. This will be used in cpu_disable so that all the topology
sibling information is removed on CPU hotplug out.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Currently numa_clear_node removes both cpu information from the NUMA
node cpumap as well as the NUMA node id from the cpu. Similarly
numa_store_cpu_info updates both percpu nodeid and NUMA cpumap.
However we need to retain the numa node id for the cpu and only remove
the cpu information from the numa node cpumap during CPU hotplug out.
The same can be extended for hotplugging in the CPU.
This patch separates out numa_{add,remove}_cpu from numa_clear_node and
numa_store_cpu_info.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Add an interface to invalidate intermediate page tables
from TLB for kernel.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Patching kernel instructions at runtime requires other CPUs to undergo
a context synchronisation event via an explicit ISB or an IPI in order
to ensure that the new instructions are visible. This is required even
for "hotpatch" instructions such as NOP and BL, so avoid optimising in
this case and always go via stop_machine() when performing general
patching.
ftrace isn't quite as strict, so it can continue to call the nosync
code directly.
Signed-off-by: Will Deacon <will.deacon@arm.com>
When invalidating the instruction cache for a kernel mapping via
flush_icache_range(), it is also necessary to flush the pipeline for
other CPUs so that instructions fetched into the pipeline before the
I-cache invalidation are discarded. For example, if module 'foo' is
unloaded and then module 'bar' is loaded into the same area of memory,
a CPU could end up executing instructions from 'foo' when branching into
'bar' if these instructions were fetched into the pipeline before 'foo'
was unloaded.
Whilst this is highly unlikely to occur in practice, particularly as
any exception acts as a context-synchronizing operation, following the
letter of the architecture requires us to execute an ISB on each CPU
in order for the new instruction stream to be visible.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Now that users have been migrated to PSR_AA32, kill the unused
COMPAT_PSR definitions.
The only difference we need a definition for is COMPAT_PSR_DIT_BIT,
which differs from PSR_AA32_DIT_BIT.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
