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Currently the SVE register save/restore sequences are written in out-of-line assembly routines. While this works, it's somewhat painful: * As KVM needs to be able to use the sequences in hyp code, separate assembly files are used for the regular kernel and KVM code. While the common logic is shared in assembly macros, this still requires some duplication, and has lead to some trivial divergence. * As the SVE LDR/STR instrucitons have limited addressing modes, the assembly macros use an awkward pattern requiring negative offsets. This could be written more clearly with addresses being generated in C code. * As the FFR does not always exist in streaming mode, some awkward conditional branching has been written in assembly which could be clearer in C (and would permit the compiler to optimize out unnecessary branches in some cases). * For historical reasons, the assembly macros take some register arguments as numerical indices (e.g. "sve_save 0, x1" uses x0 and x1), which is simply confusing. * For historical reasons, the SVE save/restore code and FPSIMD save/restore code have a distinct sequences for FPSR and FPCR. Ideally this logic would be shared. * The assembly sequences can't be instrumented, and so it's harder than necessary to catch memory safety issues. To handle the above, move the SVE register save/restore sequences to inline assembly. Neither GCC nor LLVM instrument memory arguments to inline assembly, so explicit instrumentation is added in the same manner as other assembly routines. This instrumentation is implicitly disabled by Kbuild for nVHE hyp code. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Fuad Tabba <tabba@google.com> Cc: James Morse <james.morse@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oupton@kernel.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
14 lines
403 B
Makefile
14 lines
403 B
Makefile
# SPDX-License-Identifier: GPL-2.0
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#
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# Makefile for Kernel-based Virtual Machine module, HYP/VHE part
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#
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asflags-y := -D__KVM_VHE_HYPERVISOR__
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ccflags-y := -D__KVM_VHE_HYPERVISOR__
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CFLAGS_switch.o += -Wno-override-init
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obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o
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obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
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../hyp-entry.o ../exception.o ../vgic-v5-sr.o
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