Messages in this thread | | | From | Kristina Martsenko <> | Subject | [PATCH 0/3] KVM: arm64: Support for Arm v8.8 memcpy instructions in KVM guests | Date | Fri, 15 Sep 2023 13:48:37 +0100 |
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Hi,
This series adds support for using the new Arm memory copy instructions in KVM guests. A previous series [1] added support for using the instructions in userspace applications. Similarly to that series, the main thing to note here is the handling for when a memcpy is stopped and continued on a different type of CPU. See patch #2 for details.
As background, the Armv8.8 extension adds new instructions to perform memcpy(), memset() and memmove() operations in hardware (FEAT_MOPS). The aim is to avoid having many different performance-optimal memcpy implementations in software (tailored to CPU model and copy size) and the overhead of selecting between them. The new instructions are intended to be at least as fast as any alternative instruction sequence.
The series has been tested on the Arm FVP.
Thanks, Kristina
[1] https://lore.kernel.org/all/20230509142235.3284028-1-kristina.martsenko@arm.com/
Kristina Martsenko (3): KVM: arm64: Configure HCRX_EL2 dynamically KVM: arm64: Add handler for MOPS exceptions KVM: arm64: Expose MOPS instructions to guests
arch/arm64/include/asm/kvm_emulate.h | 10 ++++ arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/include/asm/traps.h | 54 ++++++++++++++++++- arch/arm64/kernel/traps.c | 48 +---------------- arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/hyp/include/hyp/switch.h | 19 ++++++- .../arm64/kvm/hyp/include/nvhe/fixed_config.h | 3 +- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 1 + arch/arm64/kvm/hyp/nvhe/pkvm.c | 1 + arch/arm64/kvm/hyp/nvhe/switch.c | 2 + arch/arm64/kvm/hyp/vhe/switch.c | 1 + arch/arm64/kvm/sys_regs.c | 1 - 12 files changed, 90 insertions(+), 52 deletions(-)
base-commit: 0bb80ecc33a8fb5a682236443c1e740d5c917d1d -- 2.25.1
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