linux/arch/arm64/kernel
Andrei Vagin 3503d56cc7 arm64/vdso: Add time namespace page
Allocate the time namespace page among VVAR pages.  Provide
__arch_get_timens_vdso_data() helper for VDSO code to get the
code-relative position of VVARs on that special page.

If a task belongs to a time namespace then the VVAR page which contains
the system wide VDSO data is replaced with a namespace specific page
which has the same layout as the VVAR page. That page has vdso_data->seq
set to 1 to enforce the slow path and vdso_data->clock_mode set to
VCLOCK_TIMENS to enforce the time namespace handling path.

The extra check in the case that vdso_data->seq is odd, e.g. a concurrent
update of the VDSO data is in progress, is not really affecting regular
tasks which are not part of a time namespace as the task is spin waiting
for the update to finish and vdso_data->seq to become even again.

If a time namespace task hits that code path, it invokes the corresponding
time getter function which retrieves the real VVAR page, reads host time
and then adds the offset for the requested clock which is stored in the
special VVAR page.

The time-namespace page isn't allocated on !CONFIG_TIME_NAMESPACE, but
vma is the same size, which simplifies criu/vdso migration between
different kernel configs.

Signed-off-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Dmitry Safonov <dima@arista.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200624083321.144975-4-avagin@gmail.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-24 13:15:20 +01:00
..
probes arm64: use PAGE_KERNEL_ROX directly in alloc_insn_page 2020-06-26 00:27:38 -07:00
vdso arm64/vdso: Add time namespace page 2020-07-24 13:15:20 +01:00
vdso32 arm64/vdso: Add time namespace page 2020-07-24 13:15:20 +01:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
acpi_numa.c acpi: Create subtable parsing infrastructure 2019-04-04 18:41:12 +02:00
acpi_parking_protocol.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
acpi.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
alternative.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
armv8_deprecated.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
asm-offsets.c ARM: 2020-06-03 15:13:47 -07:00
cacheinfo.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
cpu_errata.c arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist 2020-06-25 20:18:57 +01:00
cpu_ops.c arm64: Introduce get_cpu_ops() helper function 2020-03-24 17:24:19 +00:00
cpu-reset.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
cpu-reset.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
cpufeature.c arm64: kpti: Add KRYO{3, 4}XX silver CPU cores to kpti safelist 2020-06-24 14:25:06 +01:00
cpuidle.c arm64: Introduce get_cpu_ops() helper function 2020-03-24 17:24:19 +00:00
cpuinfo.c Merge branch 'for-next/bti' into for-next/core 2020-05-28 18:00:51 +01:00
crash_core.c arm64/crash_core: Export KERNELPACMASK in vmcoreinfo 2020-05-11 14:29:10 +01:00
crash_dump.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
debug-monitors.c arm64: debug: mark a function as __init to save some memory 2020-06-04 16:21:29 +01:00
efi-entry.S arm64 updates for 5.8 2020-06-01 15:18:27 -07:00
efi-header.S arm64 updates for 5.8 2020-06-01 15:18:27 -07:00
efi-rt-wrapper.S Merge branch 'for-next/scs' into for-next/core 2020-05-28 18:03:40 +01:00
efi.c mm/pgtable: drop pgtable_t variable from pte_fn_t functions 2019-07-12 11:05:46 -07:00
entry-common.c Merge branch 'for-next/bti' into for-next/core 2020-05-28 18:00:51 +01:00
entry-fpsimd.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
entry-ftrace.S arm64: entry-ftrace.S: Update comment to indicate that x18 is live 2020-05-18 17:47:50 +01:00
entry.S Merge branch 'for-next/scs' into for-next/core 2020-05-28 18:03:40 +01:00
fpsimd.c arm64: sve: Fix build failure when ARM64_SVE=y and SYSCTL=n 2020-06-16 18:29:11 +01:00
ftrace.c arm64: ftrace: Change CONFIG_FTRACE_WITH_REGS to CONFIG_DYNAMIC_FTRACE_WITH_REGS 2020-06-08 15:44:59 +01:00
head.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
hibernate-asm.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
hibernate.c mm: consolidate pte_index() and pte_offset_*() definitions 2020-06-09 09:39:14 -07:00
hw_breakpoint.c arm64: hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints 2020-06-18 11:10:00 +01:00
hyp-stub.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
image-vars.h arm64: rename stext to primary_entry 2020-04-28 13:55:16 +01:00
image.h arm64/efi: Move variable assignments after SECTIONS 2019-08-14 17:18:15 +01:00
insn.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
io.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
irq.c arm64 updates for 5.3: 2019-07-08 09:54:55 -07:00
jump_label.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kaslr.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
kexec_image.c arm64: kexec_file: add crash dump support 2020-01-08 17:05:23 +00:00
kgdb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
kuser32.S docs: arm: convert docs to ReST and rename to *.rst 2019-07-15 09:20:24 -03:00
machine_kexec_file.c arm64: kexec_file: Use struct_size() in kmalloc() 2020-06-18 10:45:20 +01:00
machine_kexec.c arm64: fix the flush_icache_range arguments in machine_kexec 2020-05-11 12:02:14 +01:00
Makefile arm64: compat: Allow 32-bit vdso and sigpage to co-exist 2020-06-23 14:47:03 +01:00
module-plts.c arm64: implement ftrace with regs 2019-11-06 14:17:35 +00:00
module.c arm64: implement ftrace with regs 2019-11-06 14:17:35 +00:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c firmware: smccc: Drop smccc_version enum and use ARM_SMCCC_VERSION_1_x instead 2020-05-20 19:10:37 +01:00
pci.c PCI: Constify struct pci_ecam_ops 2020-05-01 16:28:59 +01:00
perf_callchain.c arm64: stacktrace: Factor out backtrace initialisation 2019-07-22 11:44:08 +01:00
perf_event.c arm64: perf: Add support for ARMv8.5-PMU 64-bit counters 2020-03-17 22:50:30 +00:00
perf_regs.c arm64: perf: Report the PC value in REGS_ABI_32 mode 2020-06-25 14:47:04 +01:00
pointer_auth.c arm64: install user ptrauth keys at kernel exit time 2020-03-18 09:50:19 +00:00
process.c arm64: add loglvl to dump_backtrace() 2020-06-09 09:39:11 -07:00
psci.c arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill() 2019-10-25 16:29:11 +01:00
ptrace.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
reloc_test_core.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
reloc_test_syms.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
relocate_kernel.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
return_address.c arm64: unwind: Prohibit probing on return_address() 2019-08-01 15:00:26 +01:00
scs.c scs: Move DEFINE_SCS macro into core code 2020-05-18 17:47:48 +01:00
sdei.c arm64 updates for 5.8 2020-06-01 15:18:27 -07:00
setup.c arm64: warn on incorrect placement of the kernel by the bootloader 2020-06-11 14:13:13 +01:00
signal32.c arm64: compat: Always use sigpage for sigreturn trampoline 2020-06-23 14:56:24 +01:00
signal.c arm64: Basic Branch Target Identification support 2020-03-16 17:19:48 +00:00
sigreturn32.S arm64: compat: Split kuser32 2019-04-23 18:01:57 +01:00
sleep.S Merge branch 'for-next/bti' into for-next/core 2020-05-28 18:00:51 +01:00
smccc-call.S arm64: kernel: Convert to modern annotations for assembly functions 2020-05-04 12:46:03 +01:00
smp_spin_table.c arm64: prefer __section from compiler_attributes.h 2019-08-13 18:32:15 +01:00
smp.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
ssbd.c Return ENODEV when the selected speculation misfeature is unsupported 2020-01-08 17:27:41 +00:00
stacktrace.c arm64: unwind: strip PAC from kernel addresses 2020-03-18 09:50:20 +00:00
suspend.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
sys32.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 452 2019-06-19 17:09:08 +02:00
sys_compat.c arm64: Silence clang warning on mismatched value/register sizes 2019-10-28 09:13:21 +00:00
sys.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234 2019-06-19 17:09:07 +02:00
syscall.c arm64: Basic Branch Target Identification support 2020-03-16 17:19:48 +00:00
time.c arm64: time: Replace <linux/clk-provider.h> by <linux/of_clk.h> 2020-02-12 17:26:38 +00:00
topology.c arm64: use activity monitors for frequency invariance 2020-03-06 16:02:50 +00:00
trace-events-emulation.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
traps.c arm64 fixes for -rc2 2020-06-19 12:19:12 -07:00
vdso.c arm64/vdso: Add time namespace page 2020-07-24 13:15:20 +01:00
vmlinux.lds.S mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00