Introduce '.hyp.data..percpu' as part of ongoing effort to make nVHE
hyp code self-contained and independent of the rest of the kernel.
The series builds on top of the "Split off nVHE hyp code" series which
used objcopy to rename '.text' to '.hyp.text' and prefix all ELF
symbols with '__kvm_nvhe' for all object files under kvm/hyp/nvhe.
The series is structured as follows:
- patch 1: Modify generic PERCPU_* linker script macros to make it
possible to define multiple per-CPU ELF sections with prefixed
section and symbol names.
- patch 2: Improve existing hyp build rules. This could be sent and merged
independently of per-CPU but this series builds on it.
- patches 3-4: Replace hyp helpers for accessing per-CPU variables
with common helpers modified to work correctly in hyp. Per-CPU
variables can now be accessed with one API anywhere.
- patches 5-7: Where VHE and nVHE use per-CPU variables defined in
kernel proper, move their definitions to hyp/ where they are
duplicated and owned by VHE/nVHE, respectively. Non-VHE hyp code
now refers only to per-CPU variables defined in its source files.
Helpers are added so that kernel proper can continue to access
nVHE hyp variables, same way as it does with other nVHE symbols.
- patches 8-10: Introduce '.hyp.data..percpu' ELF section and allocate
memory for every CPU core during KVM init. All nVHE per-CPU state
is now grouped together in ELF and in memory. Introducing a new
per-CPU variable does not require adding new memory mappings any
more. nVHE hyp code cannot accidentally refer to kernel-proper
per-CPU data as it only has the pointer to its own per-CPU memory.
Patches are rebased on v5.9-rc3 and available in branch 'topic/percpu-v2' at:
https://android-kvm.googlesource.com/linux
Changes v1 -> v2:
* 5.9-rc3 base
* partially link hyp code, add linker script
David Brazdil (10):
Macros to override naming of percpu symbols and sections
kvm: arm64: Partially link nVHE hyp code, simplify HYPCOPY
kvm: arm64: Remove __hyp_this_cpu_read
kvm: arm64: Remove hyp_adr/ldr_this_cpu
kvm: arm64: Add helpers for accessing nVHE hyp per-cpu vars
kvm: arm64: Duplicate arm64_ssbd_callback_required for nVHE hyp
kvm: arm64: Create separate instances of kvm_host_data for VHE/nVHE
kvm: arm64: Mark hyp stack pages reserved
kvm: arm64: Set up hyp percpu data for nVHE
kvm: arm64: Remove unnecessary hyp mappings
arch/arm64/include/asm/assembler.h | 27 ++++--
arch/arm64/include/asm/kvm_asm.h | 74 ++++++++-------
arch/arm64/include/asm/kvm_host.h | 2 +-
arch/arm64/include/asm/kvm_mmu.h | 23 ++---
arch/arm64/include/asm/percpu.h | 33 ++++++-
arch/arm64/include/asm/sections.h | 1 +
arch/arm64/kernel/image-vars.h | 2 -
arch/arm64/kernel/vmlinux.lds.S | 10 ++
arch/arm64/kvm/arm.c | 110 ++++++++++++++++++----
arch/arm64/kvm/hyp/hyp-entry.S | 2 +-
arch/arm64/kvm/hyp/include/hyp/debug-sr.h | 4 +-
arch/arm64/kvm/hyp/include/hyp/switch.h | 8 +-
arch/arm64/kvm/hyp/nvhe/Makefile | 56 +++++------
arch/arm64/kvm/hyp/nvhe/hyp.lds.S | 19 ++++
arch/arm64/kvm/hyp/nvhe/switch.c | 8 +-
arch/arm64/kvm/hyp/vhe/switch.c | 5 +-
arch/arm64/kvm/hyp/vhe/sysreg-sr.c | 4 +-
arch/arm64/kvm/pmu.c | 13 ++-
include/asm-generic/vmlinux.lds.h | 40 +++++---
19 files changed, 304 insertions(+), 137 deletions(-)
create mode 100644 arch/arm64/kvm/hyp/nvhe/hyp.lds.S
--
2.28.0.402.g5ffc5be6b7-goog
