From: Oliver Upton Date: Mon, 13 Feb 2023 23:33:41 +0000 (+0000) Subject: Merge branch kvm-arm64/nv-prefix into kvmarm/next X-Git-Tag: v6.6.7~3413^2~2^2^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0d3b2b4d2364166a955d03407ddace9269c603a5;p=platform%2Fkernel%2Flinux-starfive.git Merge branch kvm-arm64/nv-prefix into kvmarm/next * kvm-arm64/nv-prefix: : Preamble to NV support, courtesy of Marc Zyngier. : : This brings in a set of prerequisite patches for supporting nested : virtualization in KVM/arm64. Of course, there is a long way to go until : NV is actually enabled in KVM. : : - Introduce cpucap / vCPU feature flag to pivot the NV code on : : - Add support for EL2 vCPU register state : : - Basic nested exception handling : : - Hide unsupported features from the ID registers for NV-capable VMs KVM: arm64: nv: Use reg_to_encoding() to get sysreg ID KVM: arm64: nv: Only toggle cache for virtual EL2 when SCTLR_EL2 changes KVM: arm64: nv: Filter out unsupported features from ID regs KVM: arm64: nv: Emulate EL12 register accesses from the virtual EL2 KVM: arm64: nv: Allow a sysreg to be hidden from userspace only KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor KVM: arm64: nv: Add accessors for SPSR_EL1, ELR_EL1 and VBAR_EL1 from virtual EL2 KVM: arm64: nv: Handle SMCs taken from virtual EL2 KVM: arm64: nv: Handle trapped ERET from virtual EL2 KVM: arm64: nv: Inject HVC exceptions to the virtual EL2 KVM: arm64: nv: Support virtual EL2 exceptions KVM: arm64: nv: Handle HCR_EL2.NV system register traps KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state KVM: arm64: nv: Add EL2 system registers to vcpu context KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x KVM: arm64: nv: Reset VCPU to EL2 registers if VCPU nested virt is set KVM: arm64: nv: Introduce nested virtualization VCPU feature KVM: arm64: Use the S2 MMU context to iterate over S2 table arm64: Add ARM64_HAS_NESTED_VIRT cpufeature Signed-off-by: Oliver Upton --- 0d3b2b4d2364166a955d03407ddace9269c603a5 diff --cc arch/arm64/include/asm/kvm_arm.h index 5a4b234,e24825d..baef29f --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@@ -345,8 -344,9 +345,8 @@@ ECN(SP_ALIGN), ECN(FP_EXC32), ECN(FP_EXC64), ECN(SERROR), \ ECN(BREAKPT_LOW), ECN(BREAKPT_CUR), ECN(SOFTSTP_LOW), \ ECN(SOFTSTP_CUR), ECN(WATCHPT_LOW), ECN(WATCHPT_CUR), \ - ECN(BKPT32), ECN(VECTOR32), ECN(BRK64) + ECN(BKPT32), ECN(VECTOR32), ECN(BRK64), ECN(ERET) -#define CPACR_EL1_TTA (1 << 28) #define CPACR_EL1_DEFAULT (CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN |\ CPACR_EL1_ZEN_EL1EN) diff --cc arch/arm64/kvm/sys_regs.c index 0bc7df5,82c1f8d..53749d3 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@@ -85,96 -85,36 +86,108 @@@ void vcpu_write_sys_reg(struct kvm_vcp /* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */ #define CSSELR_MAX 14 +/* + * Returns the minimum line size for the selected cache, expressed as + * Log2(bytes). + */ +static u8 get_min_cache_line_size(bool icache) +{ + u64 ctr = read_sanitised_ftr_reg(SYS_CTR_EL0); + u8 field; + + if (icache) + field = SYS_FIELD_GET(CTR_EL0, IminLine, ctr); + else + field = SYS_FIELD_GET(CTR_EL0, DminLine, ctr); + + /* + * Cache line size is represented as Log2(words) in CTR_EL0. + * Log2(bytes) can be derived with the following: + * + * Log2(words) + 2 = Log2(bytes / 4) + 2 + * = Log2(bytes) - 2 + 2 + * = Log2(bytes) + */ + return field + 2; +} + /* Which cache CCSIDR represents depends on CSSELR value. */ -static u32 get_ccsidr(u32 csselr) +static u32 get_ccsidr(struct kvm_vcpu *vcpu, u32 csselr) +{ + u8 line_size; + + if (vcpu->arch.ccsidr) + return vcpu->arch.ccsidr[csselr]; + + line_size = get_min_cache_line_size(csselr & CSSELR_EL1_InD); + + /* + * Fabricate a CCSIDR value as the overriding value does not exist. + * The real CCSIDR value will not be used as it can vary by the + * physical CPU which the vcpu currently resides in. + * + * The line size is determined with get_min_cache_line_size(), which + * should be valid for all CPUs even if they have different cache + * configuration. + * + * The associativity bits are cleared, meaning the geometry of all data + * and unified caches (which are guaranteed to be PIPT and thus + * non-aliasing) are 1 set and 1 way. + * Guests should not be doing cache operations by set/way at all, and + * for this reason, we trap them and attempt to infer the intent, so + * that we can flush the entire guest's address space at the appropriate + * time. The exposed geometry minimizes the number of the traps. + * [If guests should attempt to infer aliasing properties from the + * geometry (which is not permitted by the architecture), they would + * only do so for virtually indexed caches.] + * + * We don't check if the cache level exists as it is allowed to return + * an UNKNOWN value if not. + */ + return SYS_FIELD_PREP(CCSIDR_EL1, LineSize, line_size - 4); +} + +static int set_ccsidr(struct kvm_vcpu *vcpu, u32 csselr, u32 val) { - u32 ccsidr; + u8 line_size = FIELD_GET(CCSIDR_EL1_LineSize, val) + 4; + u32 *ccsidr = vcpu->arch.ccsidr; + u32 i; + + if ((val & CCSIDR_EL1_RES0) || + line_size < get_min_cache_line_size(csselr & CSSELR_EL1_InD)) + return -EINVAL; + + if (!ccsidr) { + if (val == get_ccsidr(vcpu, csselr)) + return 0; + + ccsidr = kmalloc_array(CSSELR_MAX, sizeof(u32), GFP_KERNEL_ACCOUNT); + if (!ccsidr) + return -ENOMEM; - /* Make sure noone else changes CSSELR during this! */ - local_irq_disable(); - write_sysreg(csselr, csselr_el1); - isb(); - ccsidr = read_sysreg(ccsidr_el1); - local_irq_enable(); + for (i = 0; i < CSSELR_MAX; i++) + ccsidr[i] = get_ccsidr(vcpu, i); - return ccsidr; + vcpu->arch.ccsidr = ccsidr; + } + + ccsidr[csselr] = val; + + return 0; } + static bool access_rw(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) + { + if (p->is_write) + vcpu_write_sys_reg(vcpu, p->regval, r->reg); + else + p->regval = vcpu_read_sys_reg(vcpu, r->reg); + + return true; + } + /* * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized). */