linux_dsm_epyc7002/arch/arm64/kernel
Christoffer Dall 4464e210de KVM: arm64: Avoid storing the vcpu pointer on the stack
We already have the percpu area for the host cpu state, which points to
the VCPU, so there's no need to store the VCPU pointer on the stack on
every context switch.  We can be a little more clever and just use
tpidr_el2 for the percpu offset and load the VCPU pointer from the host
context.

This has the benefit of being able to retrieve the host context even
when our stack is corrupted, and it has a potential performance benefit
because we trade a store plus a load for an mrs and a load on a round
trip to the guest.

This does require us to calculate the percpu offset without including
the offset from the kernel mapping of the percpu array to the linear
mapping of the array (which is what we store in tpidr_el1), because a
PC-relative generated address in EL2 is already giving us the hyp alias
of the linear mapping of a kernel address.  We do this in
__cpu_init_hyp_mode() by using kvm_ksym_ref().

The code that accesses ESR_EL2 was previously using an alternative to
use the _EL1 accessor on VHE systems, but this was actually unnecessary
as the _EL1 accessor aliases the ESR_EL2 register on VHE, and the _EL2
accessor does the same thing on both systems.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19 10:53:09 +00:00
..
probes License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vdso arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
.gitignore arm64: Build infrastructure 2012-09-17 13:42:21 +01:00
acpi_numa.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
acpi_parking_protocol.c arm64: fix endianness annotation in acpi_parking_protocol.c 2017-06-29 11:33:15 +01:00
acpi.c More ACPI updates for v4.16-rc1 2018-02-09 09:44:25 -08:00
alternative.c arm64: alternatives: use tpidr_el2 on VHE hosts 2018-01-13 10:44:33 +00:00
arm64ksyms.c arm64: uaccess: Mask __user pointers for __arch_{clear, copy_*}_user 2018-02-06 22:53:40 +00:00
armv8_deprecated.c arm64: uaccess: Formalise types for access_ok() 2018-02-19 13:59:58 +00:00
asm-offsets.c KVM: arm64: Avoid storing the vcpu pointer on the stack 2018-03-19 10:53:09 +00:00
bpi.S arm64: Kill PSCI_GET_VERSION as a variant-2 workaround 2018-02-06 22:54:18 +00:00
cacheinfo.c arm64: cacheinfo: Remove CCSIDR-based cache information probing 2017-03-20 16:16:54 +00:00
cpu_errata.c arm64: Add missing Falkor part number for branch predictor hardening 2018-02-12 11:28:45 +00:00
cpu_ops.c arm64: cpu_ops: Add missing 'const' qualifiers 2017-12-01 13:05:08 +00:00
cpu-reset.h arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
cpu-reset.S arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives 2018-02-06 22:53:27 +00:00
cpufeature.c arm64: cpufeature: Fix CTR_EL0 field definitions 2018-02-19 17:02:09 +00:00
cpuidle.c ARM64 / cpuidle: Use new cpuidle macro for entering retention state 2018-01-02 13:50:34 +00:00
cpuinfo.c arm64: v8.4: Support for new floating point multiplication instructions 2018-01-05 11:29:48 +00:00
crash_dump.c arm64: kdump: provide /proc/vmcore file 2017-04-05 18:31:38 +01:00
debug-monitors.c signal: Don't use structure initializers for struct siginfo 2018-01-22 19:07:08 -06:00
efi-entry.S arm64: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +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: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
entry32.S arm64: entry32: remove pointless register assignment 2015-07-10 16:47:13 +01:00
entry-fpsimd.S arm64/sve: Low-level SVE architectural state manipulation functions 2017-11-03 15:24:14 +00:00
entry-ftrace.S arm64: Fix static use of function graph 2017-11-03 12:05:23 +00:00
entry.S 2nd set of arm64 updates for 4.16: 2018-02-08 10:44:25 -08:00
fpsimd.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-01-30 14:18:52 -08:00
ftrace.c arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
head.S arm64/kvm: Prohibit guest LOR accesses 2018-02-26 10:48:01 +01:00
hibernate-asm.S arm64: assembler: Change order of macro arguments in phys_to_ttbr 2018-02-06 22:53:21 +00:00
hibernate.c arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables 2018-02-16 18:13:57 +00:00
hw_breakpoint.c arm64: hw_breakpoint: Use linux/uaccess.h instead of asm/uaccess.h 2017-12-12 11:53:26 +00:00
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 arm64 updates for 4.13: 2017-07-05 17:09:27 -07:00
io.c arm64: Avoid aligning normal memory pointers in __memcpy_{to,from}io 2017-10-24 16:23:07 +01:00
irq.c arm64: Add vmap_stack header file 2018-01-13 10:45:03 +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: Adjust the offset to avoid Image across alignment boundary 2017-08-22 18:15:42 +01:00
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 arm64: Add __NR_* definitions for compat syscalls 2014-07-10 11:02:40 +01:00
machine_kexec.c arm64: explicitly mask all exceptions 2017-11-02 15:55:40 +00:00
Makefile arm64: kernel: Add arch-specific SDEI entry code and CPU masking 2018-01-13 10:45:17 +00:00
module-plts.c arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
module.c arm64: fix endianness annotation for reloc_insn_movw() & reloc_insn_imm() 2017-06-29 11:09:39 +01:00
module.lds arm64: ftrace: emit ftrace-mod.o contents through code 2017-12-01 13:04:59 +00:00
paravirt.c arm64: introduce CONFIG_PARAVIRT, PARAVIRT_TIME_ACCOUNTING and pv_time_ops 2015-12-21 14:40:54 +00:00
pci.c PCI: Add a generic weak pcibios_align_resource() 2017-08-02 14:53:16 -05:00
perf_callchain.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
perf_event.c arm64: perf: correct PMUVer probing 2018-02-20 11:34:54 +00:00
perf_regs.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
process.c arm64: __show_regs: Only resolve kernel symbols when running at EL1 2018-02-19 17:07:12 +00:00
psci.c arm64: Use __pa_symbol for kernel symbols 2017-01-12 15:05:39 +00:00
ptrace.c treewide/trivial: Remove ';;$' typo noise 2018-02-22 10:59:33 +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: Add software workaround for Falkor erratum 1041 2018-02-06 22:53:13 +00:00
return_address.c arm64: unwind: remove sp from struct stackframe 2017-08-09 14:10:29 +01:00
sdei.c arm64: sdei: Add trampoline code for remapping the kernel 2018-01-14 18:49:50 +00:00
setup.c arm64: Move the async/fiq helpers to explicitly set process context flags 2017-11-02 15:55:41 +00:00
signal32.c Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2018-01-30 14:18:52 -08:00
signal.c arm64: fpsimd: Fix state leakage when migrating after sigreturn 2018-01-16 14:39:50 +00:00
sleep.S arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives 2018-02-06 22:53:27 +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: kernel: Add arch-specific SDEI entry code and CPU masking 2018-01-13 10:45:17 +00:00
stacktrace.c arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
suspend.c arm64: uaccess: Add PAN helper 2018-01-13 10:45:10 +00:00
sys32.c arm64: fix implementation of mmap2 compat syscall 2015-03-19 10:43:51 +00:00
sys_compat.c arm64: uaccess: Formalise types for access_ok() 2018-02-19 13:59:58 +00:00
sys.c arm64: compat: Check for AArch32 state 2016-04-20 12:22:42 +01:00
time.c arm64: fix unwind_frame() for filtered out fn for function graph tracing 2018-02-23 13:46:38 +00:00
topology.c arm64: Use of_cpu_node_to_id helper for CPU topology parsing 2018-01-02 16:43:12 +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: Remove unimplemented syscall log message 2018-02-19 17:05:53 +00:00
vdso.c arm64/vdso: Support mremap() for vDSO 2017-08-09 12:16:28 +01:00
vmlinux.lds.S arm64: Extend early page table code to allow for larger kernels 2018-01-14 18:49:52 +00:00