linux/arch/arm64/include/asm
Will Deacon 75a19a0202 arm64: arch_timer: Ensure counter register reads occur with seqlock held
When executing clock_gettime(), either in the vDSO or via a system call,
we need to ensure that the read of the counter register occurs within
the seqlock reader critical section. This ensures that updates to the
clocksource parameters (e.g. the multiplier) are consistent with the
counter value and therefore avoids the situation where time appears to
go backwards across multiple reads.

Extend the vDSO logic so that the seqlock critical section covers the
read of the counter register as well as accesses to the data page. Since
reads of the counter system registers are not ordered by memory barrier
instructions, introduce dependency ordering from the counter read to a
subsequent memory access so that the seqlock memory barriers apply to
the counter access in both the vDSO and the system call paths.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30 11:04:23 +01:00
..
xen arm64/xen: fix xen-swiotlb cache flushing 2019-01-23 22:14:56 +01:00
acenv.h
acpi.h arm64: KVM/mm: Move SEA handling behind a single 'claim' interface 2019-02-07 23:10:45 +01:00
alternative.h arm64: alternative: Apply alternatives early in boot process 2019-02-06 10:05:20 +00:00
arch_gicv3.h arm64: gic-v3: Implement arch support for priority masking 2019-02-06 10:05:21 +00:00
arch_timer.h arm64: arch_timer: Ensure counter register reads occur with seqlock held 2019-04-30 11:04:23 +01:00
arm_dsu_pmu.h perf: ARM DynamIQ Shared Unit PMU support 2018-01-02 16:43:12 +00:00
arm-cci.h
asm-bug.h arm64: asm-bug: Renumber macro local labels to avoid clashes 2017-10-25 15:57:15 +01:00
asm-offsets.h
asm-prototypes.h arm64: asm-prototypes: Fix fat-fingered typo in comment 2019-01-10 11:11:46 +00:00
asm-uaccess.h arm64: Rename get_thread_info() 2019-02-26 16:57:59 +00:00
assembler.h arm64: add CVADP support to the cache maintenance helper 2019-04-16 16:27:58 +01:00
atomic_ll_sc.h Merge branch 'locking/atomics' into locking/core, to pick up WIP commits 2019-02-11 14:27:05 +01:00
atomic_lse.h Merge branch 'locking/atomics' into locking/core, to pick up WIP commits 2019-02-11 14:27:05 +01:00
atomic.h arm64, locking/atomics: Use instrumented atomics 2018-11-01 11:01:40 +01:00
barrier.h arm64: instrument smp_{load_acquire,store_release} 2019-04-16 16:28:00 +01:00
bitops.h locking/atomics/arm64, arm64/bitops: Include <asm-generic/bitops/ext2-atomic-setbit.h> 2018-06-21 12:52:12 +02:00
bitrev.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
boot.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
brk-imm.h arm64: probes: Move magic BRK values into brk-imm.h 2019-04-09 11:21:13 +01:00
bug.h
cache.h kasan, arm64: remove redundant ARCH_SLAB_MINALIGN define 2019-01-16 12:09:11 +00:00
cacheflush.h arm64: IPI each CPU after invalidating the I-cache for kernel mappings 2018-07-05 17:24:36 +01:00
checksum.h
clocksource.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cmpxchg.h Merge branch 'locking/atomics' into locking/core, to pick up WIP commits 2019-02-11 14:27:05 +01:00
compat.h Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-25 11:14:36 -07:00
cpu_ops.h
cpu.h arm64/sve: Probe SVE capabilities and usable vector lengths 2017-11-03 15:24:17 +00:00
cpucaps.h arm64: Advertise ARM64_HAS_DCPODP cpu feature 2019-04-16 16:27:59 +01:00
cpufeature.h arm64: HWCAP: encapsulate elf_hwcap 2019-04-16 16:27:35 +01:00
cpuidle.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cputype.h arm64: Add MIDR encoding for HiSilicon Taishan CPUs 2019-03-19 14:55:10 +00:00
current.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
daifflags.h arm64 updates for 5.1: 2019-03-10 10:17:23 -07:00
dcc.h
debug-monitors.h arm64: probes: Move magic BRK values into brk-imm.h 2019-04-09 11:21:13 +01:00
device.h arm64/xen: fix xen-swiotlb cache flushing 2019-01-23 22:14:56 +01:00
dma-mapping.h dma-mapping: add a kconfig symbol for arch_teardown_dma_ops availability 2019-02-13 19:12:50 +01:00
dmi.h
efi.h arm64: irqflags: Use ICC_PMR_EL1 for interrupt masking 2019-02-06 10:05:19 +00:00
elf.h arm64: compat: Alloc separate pages for vectors and sigpage 2019-04-23 18:01:31 +01:00
esr.h arm64: Handle trapped DC CVADP 2019-04-16 16:27:36 +01:00
exception.h arm64: kernel: Prepare for a DISR user 2018-01-16 15:07:12 +00:00
exec.h
extable.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fb.h
fixmap.h firmware: arm_sdei: Add ACPI GHES registration helper 2019-02-11 11:07:49 +01:00
fpsimd.h arm64: move sve_user_{enable,disable} to <asm/fpsimd.h> 2018-07-12 14:40:39 +01:00
fpsimdmacros.h arm64/sve: Write ZCR_EL1 on context switch only if changed 2018-05-17 18:19:53 +01:00
ftrace.h arm64 festive updates for 4.21 2018-12-25 17:41:56 -08:00
futex.h Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
hardirq.h arm64: Fix HCR.TGE status for NMI contexts 2019-02-06 10:05:16 +00:00
hugetlb.h arm64/mm: enable HugeTLB migration for contiguous bit HugeTLB pages 2019-03-05 21:07:15 -08:00
hw_breakpoint.h perf/hw_breakpoint: Remove default hw_breakpoint_arch_parse() 2018-06-26 09:07:58 +02:00
hwcap.h arm64: Expose SVE2 features for userspace 2019-04-23 18:02:00 +01:00
hypervisor.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
image.h arm64: add image head flag definitions 2018-12-06 14:38:51 +00:00
insn.h arm64/insn: add support for emitting ADR/ADRP instructions 2018-11-27 18:47:33 +00:00
io.h arm64: io: Hook up __io_par() for inX() ordering 2019-02-28 17:24:27 +00:00
irq_work.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
irq.h arm64: Use the new GENERIC_IRQ_MULTI_HANDLER 2018-08-03 12:14:09 +02:00
irqflags.h arm64: sysreg: Make mrs_s and msr_s macros work with Clang and LTO 2019-04-25 14:59:49 +01:00
jump_label.h arm64/kernel: jump_label: Switch to relative references 2018-09-27 17:56:47 +02:00
kasan.h kasan: add tag related helper functions 2018-12-28 12:11:43 -08:00
Kbuild arm64: preempt: Provide our own implementation of asm/preempt.h 2018-12-07 12:35:53 +00:00
kernel-pgtable.h arm64/mm: Separate boot-time page tables from swapper_pg_dir 2018-09-25 15:10:54 +01:00
kexec.h arm64: kexec_file: allow for loading Image-format kernel 2018-12-06 14:38:52 +00:00
kgdb.h
kprobes.h arm64: kprobes: Avoid calling kprobes debug handlers explicitly 2019-04-09 11:21:13 +01:00
kvm_arm.h * ARM: selftests improvements, large PUD support for HugeTLB, 2018-12-26 11:46:28 -08:00
kvm_asm.h arm/arm64: KVM: Add ARM_EXCEPTION_IS_TRAP macro 2018-12-19 17:47:53 +00:00
kvm_coproc.h
kvm_emulate.h arm64: KVM: Describe data or unified caches as having 1 set and 1 way 2019-02-19 21:05:49 +00:00
kvm_host.h ARM: some cleanups, direct physical timer assignment, cache sanitization 2019-03-15 15:00:28 -07:00
kvm_hyp.h arm64: sysreg: Make mrs_s and msr_s macros work with Clang and LTO 2019-04-25 14:59:49 +01:00
kvm_mmio.h
kvm_mmu.h KVM: arm/arm64: vgic-its: Take the srcu lock when writing to guest memory 2019-03-19 17:56:56 +00:00
kvm_ras.h arm64: KVM/mm: Move SEA handling behind a single 'claim' interface 2019-02-07 23:10:45 +01:00
linkage.h arm64: relax assembly code alignment from 16 byte to 4 byte 2017-09-18 11:20:19 +01:00
lse.h arm64: lse: Include compiler_types.h and export.h for out-of-line LL/SC 2018-03-27 13:14:49 +01:00
memory.h arm64: mm: check virtual addr in virt_to_page() if CONFIG_DEBUG_VIRTUAL=y 2019-04-16 16:27:59 +01:00
mmu_context.h arm64: Kconfig: Re-jig CONFIG options for 52-bit VA 2018-12-10 18:42:18 +00:00
mmu.h arm64: Remove asm/memblock.h 2019-01-21 17:31:15 +00:00
mmzone.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
module.h arm64/module: switch to ADRP/ADD sequences for PLT entries 2018-11-27 19:00:45 +00:00
neon-intrinsics.h arm64/neon: Disable -Wincompatible-pointer-types when building with Clang 2019-02-18 10:54:47 +00:00
neon.h arm64: drop unused kernel_neon_begin_partial() macro 2018-07-31 10:13:50 +01:00
numa.h arm64: numa: separate out updates to percpu nodeid and NUMA node cpumap 2018-07-06 13:18:18 +01:00
page-def.h
page.h arm64: Kconfig: Remove ARCH_HAS_HOLES_MEMORYMODEL 2018-09-21 12:02:45 +01:00
paravirt.h x86/paravirt: Use a single ops structure 2018-09-03 16:50:35 +02:00
pci.h PCI: remove PCI_DMA_BUS_IS_PHYS 2018-05-07 07:15:41 +02:00
percpu.h arm64: percpu: Fix LSE implementation of value-returning pcpu atomics 2018-12-12 14:43:35 +00:00
perf_event.h arm64: perf: Treat EXCLUDE_EL* bit definitions as unsigned 2018-12-13 15:34:44 +00:00
pgalloc.h arm64: mm: enable per pmd page table lock 2019-04-09 11:21:50 +01:00
pgtable-hwdef.h arm64: Add workaround for Fujitsu A64FX erratum 010001 2019-02-28 16:24:25 +00:00
pgtable-prot.h arm64: kpti: Avoid rewriting early page tables when KASLR is enabled 2019-01-10 17:49:35 +00:00
pgtable-types.h
pgtable.h * ARM: selftests improvements, large PUD support for HugeTLB, 2018-12-26 11:46:28 -08:00
pointer_auth.h arm64: Use the correct style for SPDX License Identifier 2019-04-16 16:28:01 +01:00
preempt.h arm64: preempt: Provide our own implementation of asm/preempt.h 2018-12-07 12:35:53 +00:00
probes.h
proc-fns.h arm64: mm: Move ASID from TTBR0 to TTBR1 2017-12-11 13:40:25 +00:00
processor.h arm64: compat: Reduce address limit 2019-04-10 17:38:12 +01:00
ptdump.h arm64: dump: no need to check return value of debugfs_create functions 2019-01-31 17:38:19 +00:00
ptrace.h arm64: ptrace: Add function argument access API 2019-04-12 17:04:27 +01:00
sdei.h arm64: Use the correct style for SPDX License Identifier 2019-04-16 16:28:01 +01:00
seccomp.h
sections.h arm64: mmu: add the entry trampolines start/end section markers into sections.h 2018-01-14 18:49:50 +00:00
shmparam.h
signal32.h arm64: compat: Alloc separate pages for vectors and sigpage 2019-04-23 18:01:31 +01:00
simd.h arm64: neon: Fix function may_use_simd() return error status 2018-07-11 17:02:02 +01:00
smp_plat.h
smp.h arm64: smp: Fix compilation error 2019-01-03 15:14:32 +00:00
sparsemem.h arm64: add kconfig symbol to configure physical address size 2017-12-22 17:30:33 +00:00
spinlock_types.h arm64: locking: Replace ticket lock implementation with qspinlock 2018-07-05 10:05:06 +01:00
spinlock.h arm64: locking: Replace ticket lock implementation with qspinlock 2018-07-05 10:05:06 +01:00
stack_pointer.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stackprotector.h arm64: enable per-task stack canaries 2018-12-12 18:45:31 +00:00
stacktrace.h arm64: Add stack information to on_accessible_stack 2018-07-26 11:36:07 +01:00
stage2_pgtable.h KVM: ARM: Remove pgtable page standard functions from stage-2 page tables 2019-04-09 11:21:50 +01:00
stat.h y2038: globally rename compat_time to old_time32 2018-08-27 14:48:48 +02:00
string.h arm64: lib: use C string functions with KASAN enabled 2018-10-26 16:25:18 -07:00
suspend.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sync_bitops.h arm64, locking/atomics: Use instrumented atomics 2018-11-01 11:01:40 +01:00
syscall_wrapper.h arm64: implement syscall wrappers 2018-07-12 14:49:48 +01:00
syscall.h arm64: implement syscall wrappers 2018-07-12 14:49:48 +01:00
sysreg.h arm64: sysreg: Make mrs_s and msr_s macros work with Clang and LTO 2019-04-25 14:59:49 +01:00
system_misc.h arm64: mm: Make show_pte() a static function 2019-04-03 13:36:54 +01:00
thread_info.h arm64: Remove documentation about TIF_USEDFPU 2019-02-26 16:41:10 +00:00
timex.h arm64: Use physical counter for in-kernel reads when booted in EL2 2017-11-06 16:23:09 +01:00
tlb.h arm64: mm: enable per pmd page table lock 2019-04-09 11:21:50 +01:00
tlbflush.h arm64 festive updates for 4.21 2018-12-25 17:41:56 -08:00
topology.h sched/topology, arch/arm64: Rebuild the sched_domain hierarchy when the CPU capacity changes 2018-09-10 11:05:47 +02:00
traps.h signal/arm64: Add and use arm64_force_sig_ptrace_errno_trap 2018-09-27 21:55:15 +02:00
uaccess.h arm64 updates for 5.1: 2019-03-10 10:17:23 -07:00
unistd32.h y2038: add 64-bit time_t syscalls to all 32-bit architectures 2019-02-07 00:13:28 +01:00
unistd.h y2038: add 64-bit time_t syscalls to all 32-bit architectures 2019-02-07 00:13:28 +01:00
uprobes.h
vdso_datapage.h arm64: vdso: Fix clock_getres() for CLOCK_REALTIME 2019-04-16 18:15:56 +01:00
vdso.h
virt.h arm64: capabilities: Change scope of VHE to Boot CPU feature 2018-03-26 18:01:41 +01:00
vmap_stack.h arm64: Use the correct style for SPDX License Identifier 2019-04-16 16:28:01 +01:00
word-at-a-time.h
xor.h arm64: crypto: add NEON accelerated XOR implementation 2018-12-06 16:47:06 +00:00