Commit d808f0b1 authored by Anup Patel's avatar Anup Patel Committed by Anup Patel
Browse files

RISC-V: KVM: Forward SEED CSR access to user space 



The SEED CSR access from VS/VU mode (guest) will always trap to
HS-mode (KVM) when Zkr extension is available to the Guest/VM.

Forward this CSR access to KVM user space so that it can be
emulated based on the method chosen by VMM.

Fixes: f370b4e6 ("RISC-V: KVM: Allow scalar crypto extensions for Guest/VM")
Signed-off-by: default avatarAnup Patel <apatel@ventanamicro.com>
Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Signed-off-by: default avatarAnup Patel <anup@brainfault.org>
parent d0b94bcb

arch/riscv/kvm/vcpu_insn.c

+13 −0
Original line number Diff line number Diff line
@@ -7,6 +7,8 @@ 
#include <linux/bitops.h>

#include <linux/kvm_host.h>



#include <asm/cpufeature.h>



#define INSN_OPCODE_MASK	0x007c

#define INSN_OPCODE_SHIFT	2

#define INSN_OPCODE_SYSTEM	28
@@ -213,9 +215,20 @@ struct csr_func { 
		    unsigned long wr_mask);

};



static int seed_csr_rmw(struct kvm_vcpu *vcpu, unsigned int csr_num,

			unsigned long *val, unsigned long new_val,

			unsigned long wr_mask)

{

	if (!riscv_isa_extension_available(vcpu->arch.isa, ZKR))

		return KVM_INSN_ILLEGAL_TRAP;



	return KVM_INSN_EXIT_TO_USER_SPACE;

}



static const struct csr_func csr_funcs[] = {

	KVM_RISCV_VCPU_AIA_CSR_FUNCS

	KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS

	{ .base = CSR_SEED, .count = 1, .func = seed_csr_rmw },

};



/**