Add support for a "linux,pkvm-guest-firmware-memory" reserved memory region, which can be used to identify a firmware image for protected VMs.
Signed-off-by: Will Deacon <w...@kernel.org> --- arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/pkvm.c | 52 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 53 insertions(+), 1 deletion(-) create mode 100644 arch/arm64/kvm/pkvm.c diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 589921392cb1..61e054411831 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -14,7 +14,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ $(KVM)/vfio.o $(KVM)/irqchip.o \ arm.o mmu.o mmio.o psci.o perf.o hypercalls.o pvtime.o \ inject_fault.o va_layout.o handle_exit.o \ - guest.o debug.o reset.o sys_regs.o \ + guest.o debug.o pkvm.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ arch_timer.o trng.o\ vgic/vgic.o vgic/vgic-init.o \ diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c new file mode 100644 index 000000000000..7af5d03a3941 --- /dev/null +++ b/arch/arm64/kvm/pkvm.c @@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * KVM host (EL1) interface to Protected KVM (pkvm) code at EL2. + * + * Copyright (C) 2021 Google LLC + * Author: Will Deacon <w...@kernel.org> + */ + +#include <linux/kvm_host.h> +#include <linux/mm.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> + +static struct reserved_mem *pkvm_firmware_mem; + +static int __init pkvm_firmware_rmem_err(struct reserved_mem *rmem, + const char *reason) +{ + phys_addr_t end = rmem->base + rmem->size; + + kvm_err("Ignoring pkvm guest firmware memory reservation [%pa - %pa]: %s\n", + &rmem->base, &end, reason); + return -EINVAL; +} + +static int __init pkvm_firmware_rmem_init(struct reserved_mem *rmem) +{ + unsigned long node = rmem->fdt_node; + + if (kvm_get_mode() != KVM_MODE_PROTECTED) + return pkvm_firmware_rmem_err(rmem, "protected mode not enabled"); + + if (pkvm_firmware_mem) + return pkvm_firmware_rmem_err(rmem, "duplicate reservation"); + + if (!of_get_flat_dt_prop(node, "no-map", NULL)) + return pkvm_firmware_rmem_err(rmem, "missing \"no-map\" property"); + + if (of_get_flat_dt_prop(node, "reusable", NULL)) + return pkvm_firmware_rmem_err(rmem, "\"reusable\" property unsupported"); + + if (!PAGE_ALIGNED(rmem->base)) + return pkvm_firmware_rmem_err(rmem, "base is not page-aligned"); + + if (!PAGE_ALIGNED(rmem->size)) + return pkvm_firmware_rmem_err(rmem, "size is not page-aligned"); + + pkvm_firmware_mem = rmem; + return 0; +} +RESERVEDMEM_OF_DECLARE(pkvm_firmware, "linux,pkvm-guest-firmware-memory", + pkvm_firmware_rmem_init); -- 2.32.0.rc0.204.g9fa02ecfa5-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm