linux/arch/arm64/kernel
Will Deacon dbb236c1ce arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW
Recently vDSO support for CLOCK_MONOTONIC_RAW was added in
49eea433b3 ("arm64: Add support for CLOCK_MONOTONIC_RAW in
clock_gettime() vDSO"). Noticing that the core timekeeping code
never set tkr_raw.xtime_nsec, the vDSO implementation didn't
bother exposing it via the data page and instead took the
unshifted tk->raw_time.tv_nsec value which was then immediately
shifted left in the vDSO code.

Unfortunately, by accellerating the MONOTONIC_RAW clockid, it
uncovered potential 1ns time inconsistencies caused by the
timekeeping core not handing sub-ns resolution.

Now that the core code has been fixed and is actually setting
tkr_raw.xtime_nsec, we need to take that into account in the
vDSO by adding it to the shifted raw_time value, in order to
fix the user-visible inconsistency. Rather than do that at each
use (and expand the data page in the process), instead perform
the shift/addition operation when populating the data page and
remove the shift from the vDSO code entirely.

[jstultz: minor whitespace tweak, tried to improve commit
 message to make it more clear this fixes a regression]
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Acked-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: "stable #4 . 8+" <stable@vger.kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-4-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-20 10:41:51 +02:00
..
probes arm64: kprobes: remove kprobe_exceptions_notify 2017-03-10 17:41:19 +00:00
vdso arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW 2017-06-20 10:41:51 +02:00
.gitignore
acpi_numa.c arm64/numa: avoid inconsistent information to be printed 2016-09-09 14:59:08 +01:00
acpi_parking_protocol.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
acpi.c efi/bgrt: Enable ACPI BGRT handling on arm64 2017-04-05 12:27:25 +02:00
alternative.c arm64: alternatives: apply boot time fixups via the linear mapping 2017-03-23 13:54:19 +00:00
arm64ksyms.c arm64: switch to RAW_COPY_USER 2017-03-28 18:23:24 -04:00
armv8_deprecated.c arm64: armv8_deprecated: ensure extension of addr 2017-05-09 17:47:05 +01:00
asm-offsets.c arm: kernel: Add SMC structure parameter 2017-02-03 18:46:33 +00:00
cacheinfo.c arm64: cacheinfo: Remove CCSIDR-based cache information probing 2017-03-20 16:16:54 +00:00
cpu_errata.c arm64: cpu_errata: Add capability to advertise Cortex-A73 erratum 858921 2017-04-07 11:22:08 +01:00
cpu_ops.c arm64: apply __ro_after_init to some objects 2016-08-22 12:32:29 +01:00
cpu-reset.h arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
cpu-reset.S arm64: Add back cpu reset routines 2016-06-27 16:31:25 +01:00
cpufeature.c arm64/cpufeature: don't use mutex in bringup path 2017-05-17 17:00:29 +01:00
cpuidle.c arm64: kernel: Update kerneldoc for cpu_suspend() rename 2017-03-10 18:06:24 +00:00
cpuinfo.c arm64: v8.3: Support for weaker release consistency 2017-03-20 16:30:22 +00:00
crash_dump.c arm64: kdump: provide /proc/vmcore file 2017-04-05 18:31:38 +01:00
debug-monitors.c arm64: cpufeature: Make ID reg accessor naming less counterintuitive 2017-04-04 16:55:41 +01:00
efi-entry.S arm64: efi-entry.S: avoid open-coded adr_l 2017-01-17 17:41:14 +00:00
efi-header.S arm64: efi: split Image code and data into separate PE/COFF sections 2017-04-04 17:50:59 +01:00
efi.c arm64: mm: replace 'block_mappings_allowed' with 'page_mappings_only' 2016-11-07 18:15:04 +00:00
entry32.S arm64: entry32: remove pointless register assignment 2015-07-10 16:47:13 +01:00
entry-fpsimd.S
entry-ftrace.S arm64: include asm/assembler.h in entry-ftrace.S 2017-02-15 11:34:25 +00:00
entry.S arm64: entry: improve data abort handling of tagged pointers 2017-05-09 17:26:59 +01:00
fpsimd.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h> 2017-03-02 08:42:29 +01:00
ftrace.c ftrace: Add return address pointer to ftrace_ret_stack 2016-08-24 12:15:14 +02:00
head.S Merge branch 'arm64/common-sysreg' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core 2017-04-04 18:08:47 +01:00
hibernate-asm.S arm64: Introduce raw_{d,i}cache_line_size 2016-09-09 15:03:29 +01:00
hibernate.c arm64: hibernate: preserve kdump image around hibernation 2017-04-05 18:28:50 +01:00
hw_breakpoint.c arm64: hw_breakpoint: fix watchpoint matching for tagged pointers 2017-05-09 17:26:40 +01:00
hyp-stub.S arm64: hyp-stub: Zero x0 on successful stub handling 2017-04-09 07:49:35 -07:00
image.h arm64 updates for 4.7: 2016-05-16 17:17:24 -07:00
insn.c bpf, arm64: implement jiting of BPF_XADD 2017-05-02 15:04:50 -04:00
io.c arm64: optimize memcpy_{from,to}io() and memset_io() 2014-11-06 17:25:27 +00:00
irq.c arm64: remove irq_count and do_softirq_own_stack() 2015-12-21 17:26:01 +00:00
jump_label.c jump_label: Rename JUMP_LABEL_{EN,DIS}ABLE to JUMP_LABEL_{JMP,NOP} 2015-08-03 11:34:12 +02:00
kaslr.c arm64: kaslr: Fix up the kernel image alignment 2017-03-22 15:43:11 +00:00
kgdb.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
kuser32.S
machine_kexec.c arm64: kdump: add VMCOREINFO's for user-space tools 2017-04-05 18:29:47 +01:00
Makefile arm64: kdump: provide /proc/vmcore file 2017-04-05 18:31:38 +01:00
module-plts.c arm64: module: split core and init PLT sections 2017-04-26 12:31:00 +01:00
module.c arm64: Silence first allocation with CONFIG_ARM64_MODULE_PLTS=y 2017-05-11 14:43:40 +01:00
module.lds arm64: module: split core and init PLT sections 2017-04-26 12:31:00 +01:00
paravirt.c arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops 2015-12-21 14:40:54 +00:00
pci.c ARM64: PCI: Fix struct acpi_pci_root_ops allocation failure path 2017-05-25 16:52:58 +01:00
perf_callchain.c perf core: Add a 'nr' field to perf_event_callchain_context 2016-05-16 23:11:51 -03:00
perf_event.c arm64: perf: Ignore exclude_hv when kernel is running in HYP 2017-05-15 18:30:37 +01:00
perf_regs.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
process.c arm64: drop unnecessary newlines in show_regs() 2017-03-23 14:20:41 +00:00
psci.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
ptrace.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
reloc_test_core.c arm64: relocation testing module 2017-04-04 17:03:32 +01:00
reloc_test_syms.S arm64: relocation testing module 2017-04-04 17:03:32 +01:00
relocate_kernel.S arm64: Introduce raw_{d,i}cache_line_size 2016-09-09 15:03:29 +01:00
return_address.c arm64: factor out current_stack_pointer 2016-11-11 18:25:43 +00:00
setup.c arm64: Print DT machine model in setup_machine_fdt() 2017-04-28 17:09:41 +01:00
signal32.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
signal.c arm64: Add uprobe support 2016-11-07 18:15:21 +00:00
sleep.S arm64: move sp_el0 and tpidr_el1 into cpu_suspend_ctx 2016-11-11 18:25:44 +00:00
smccc-call.S firmware: qcom: scm: Fix interrupted SCM calls 2017-02-03 18:46:33 +00:00
smp_spin_table.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
smp.c arm64 updates for 4.12: 2017-05-05 12:11:37 -07:00
stacktrace.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h> 2017-03-02 08:42:36 +01:00
suspend.c arm64: move sp_el0 and tpidr_el1 into cpu_suspend_ctx 2016-11-11 18:25:44 +00:00
sys32.c arm64: fix implementation of mmap2 compat syscall 2015-03-19 10:43:51 +00:00
sys_compat.c sched/headers: Prepare for the reduction of <linux/sched.h>'s signal API dependency 2017-03-02 08:42:37 +01:00
sys.c arm64: compat: Check for AArch32 state 2016-04-20 12:22:42 +01:00
time.c arm64: ftrace: fix a stack tracer's output under function graph tracer 2015-12-21 17:26:02 +00:00
topology.c sched/headers: Prepare for new header dependencies before moving code to <linux/sched/topology.h> 2017-03-02 08:42:26 +01:00
trace-events-emulation.h arm64: Trace emulation of AArch32 legacy instructions 2014-11-20 16:35:02 +00:00
traps.c arm64: traps: fix userspace cache maintenance emulation on a tagged pointer 2017-05-09 17:26:17 +01:00
vdso.c arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW 2017-06-20 10:41:51 +02:00
vmlinux.lds.S arm64: efi: split Image code and data into separate PE/COFF sections 2017-04-04 17:50:59 +01:00