The current alternative instruction framework is not kind to branches, potentially leading to all kind of hacks in the code that uses alternatives. This series expands it to deal with immediate branches (for a start), and applies it to the VGIC world switch. Patch #1 adds the required infrastructure to extract the immediate from an instruction. Patch #2 allows the use of an immediate b or bl instruction as an alternative, computing the target branch as the instruction is being patched in. Patch #3 defines a feature framework that works exactly like the CPU errata infrastructure (and shares a lot with it). Patch #4 adds detection of the system register GICv3 CPU interface. Patch #5 enables dynamic patching of the KVM code. This has been tested with GICv3 on a FastModel. * From v1: - Fixed missing cpu_to_le32 when writing back the instruction - Added Will's Acks. Marc Zyngier (5): arm64: insn: Add aarch64_insn_decode_immediate arm64: alternative: Allow immediate branch as alternative instruction arm64: Extract feature parsing code from cpu_errata.c arm64: alternative: Introduce feature for GICv3 CPU interface arm64: KVM: Switch vgic save/restore to alternative_insn arch/arm/include/asm/kvm_host.h | 5 --- arch/arm64/include/asm/cpufeature.h | 23 ++++++++++- arch/arm64/include/asm/insn.h | 1 + arch/arm64/include/asm/kvm_host.h | 23 ----------- arch/arm64/kernel/Makefile | 2 +- arch/arm64/kernel/alternative.c | 55 ++++++++++++++++++++++++- arch/arm64/kernel/asm-offsets.c | 1 - arch/arm64/kernel/cpu_errata.c | 36 ++--------------- arch/arm64/kernel/cpufeature.c | 63 +++++++++++++++++++++++++++++ arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/kernel/insn.c | 81 +++++++++++++++++++++++++++++-------- arch/arm64/kvm/hyp.S | 18 ++------- virt/kvm/arm/vgic.c | 3 -- 13 files changed, 214 insertions(+), 98 deletions(-) create mode 100644 arch/arm64/kernel/cpufeature.c -- 2.1.4 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
