This series includes few assorted fixes for KVM RISC-V ONE_REG interface and KVM_GET_REG_LIST API.
These patches can also be found in riscv_kvm_onereg_fixes_v2 branch at: https://github.com/avpatel/linux.git
Changes since v1: - Addressed Drew's comments in PATCH4
Anup Patel (4): RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registers RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensions KVM: riscv: selftests: Fix ISA_EXT register handling in get-reg-list KVM: riscv: selftests: Selectively filter-out AIA registers
arch/riscv/kvm/vcpu_onereg.c | 7 ++- .../selftests/kvm/riscv/get-reg-list.c | 58 ++++++++++++++----- 2 files changed, 47 insertions(+), 18 deletions(-)
The ISA_EXT registers to enabled/disable ISA extensions for VCPU are always available when underlying host has the corresponding ISA extension. The copy_isa_ext_reg_indices() called by the KVM_GET_REG_LIST API does not align with this expectation so let's fix it.
Fixes: 031f9efafc08 ("KVM: riscv: Add KVM_GET_REG_LIST API support") Signed-off-by: Anup Patel apatel@ventanamicro.com Reviewed-by: Atish Patra atishp@rivosinc.com Reviewed-by: Andrew Jones ajones@ventanamicro.com --- arch/riscv/kvm/vcpu_onereg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c index 1b7e9fa265cb..e7e833ced91b 100644 --- a/arch/riscv/kvm/vcpu_onereg.c +++ b/arch/riscv/kvm/vcpu_onereg.c @@ -842,7 +842,7 @@ static int copy_isa_ext_reg_indices(const struct kvm_vcpu *vcpu, u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_ISA_EXT | i;
isa_ext = kvm_isa_ext_arr[i]; - if (!__riscv_isa_extension_available(vcpu->arch.isa, isa_ext)) + if (!__riscv_isa_extension_available(NULL, isa_ext)) continue;
if (uindices) {
The riscv_vcpu_get_isa_ext_single() should fail with -ENOENT error when corresponding ISA extension is not available on the host.
Fixes: e98b1085be79 ("RISC-V: KVM: Factor-out ONE_REG related code to its own source file") Signed-off-by: Anup Patel apatel@ventanamicro.com Reviewed-by: Atish Patra atishp@rivosinc.com Reviewed-by: Andrew Jones ajones@ventanamicro.com --- arch/riscv/kvm/vcpu_onereg.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c index e7e833ced91b..b7e0e03c69b1 100644 --- a/arch/riscv/kvm/vcpu_onereg.c +++ b/arch/riscv/kvm/vcpu_onereg.c @@ -460,8 +460,11 @@ static int riscv_vcpu_get_isa_ext_single(struct kvm_vcpu *vcpu, reg_num >= ARRAY_SIZE(kvm_isa_ext_arr)) return -ENOENT;
- *reg_val = 0; host_isa_ext = kvm_isa_ext_arr[reg_num]; + if (!__riscv_isa_extension_available(NULL, host_isa_ext)) + return -ENOENT; + + *reg_val = 0; if (__riscv_isa_extension_available(vcpu->arch.isa, host_isa_ext)) *reg_val = 1; /* Mark the given extension as available */
Same set of ISA_EXT registers are not present on all host because ISA_EXT registers are visible to the KVM user space based on the ISA extensions available on the host. Also, disabling an ISA extension using corresponding ISA_EXT register does not affect the visibility of the ISA_EXT register itself.
Based on the above, we should filter-out all ISA_EXT registers.
Fixes: 477069398ed6 ("KVM: riscv: selftests: Add get-reg-list test") Signed-off-by: Anup Patel apatel@ventanamicro.com Reviewed-by: Andrew Jones ajones@ventanamicro.com --- .../selftests/kvm/riscv/get-reg-list.c | 35 +++++++++++-------- 1 file changed, 21 insertions(+), 14 deletions(-)
diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c index d8ecacd03ecf..76c0ad11e423 100644 --- a/tools/testing/selftests/kvm/riscv/get-reg-list.c +++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c @@ -14,17 +14,33 @@
bool filter_reg(__u64 reg) { + switch (reg & ~REG_MASK) { /* - * Some ISA extensions are optional and not present on all host, - * but they can't be disabled through ISA_EXT registers when present. - * So, to make life easy, just filtering out these kind of registers. + * Same set of ISA_EXT registers are not present on all host because + * ISA_EXT registers are visible to the KVM user space based on the + * ISA extensions available on the host. Also, disabling an ISA + * extension using corresponding ISA_EXT register does not affect + * the visibility of the ISA_EXT register itself. + * + * Based on above, we should filter-out all ISA_EXT registers. */ - switch (reg & ~REG_MASK) { + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_A: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_C: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_D: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_F: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_H: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_I: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_M: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVPBMT: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SSTC: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVINVAL: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIHINTPAUSE: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICBOM: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICBOZ: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBB: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SSAIA: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_V: + case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVNAPOT: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBA: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBS: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICNTR: @@ -50,12 +66,7 @@ static inline bool vcpu_has_ext(struct kvm_vcpu *vcpu, int ext) unsigned long value;
ret = __vcpu_get_reg(vcpu, RISCV_ISA_EXT_REG(ext), &value); - if (ret) { - printf("Failed to get ext %d", ext); - return false; - } - - return !!value; + return (ret) ? false : !!value; }
void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c) @@ -506,10 +517,6 @@ static __u64 base_regs[] = { KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(time), KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(compare), KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(state), - KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_A, - KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_C, - KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_I, - KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_M, KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_V01, KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_TIME, KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_IPI,
Currently the AIA ONE_REG registers are reported by get-reg-list as new registers for various vcpu_reg_list configs whenever Ssaia is available on the host because Ssaia extension can only be disabled by Smstateen extension which is not always available.
To tackle this, we should filter-out AIA ONE_REG registers only when Ssaia can't be disabled for a VCPU.
Fixes: 477069398ed6 ("KVM: riscv: selftests: Add get-reg-list test") Signed-off-by: Anup Patel apatel@ventanamicro.com Reviewed-by: Atish Patra atishp@rivosinc.com --- .../selftests/kvm/riscv/get-reg-list.c | 23 +++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c index 76c0ad11e423..9f99ea42f45f 100644 --- a/tools/testing/selftests/kvm/riscv/get-reg-list.c +++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c @@ -12,6 +12,8 @@
#define REG_MASK (KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK)
+static bool isa_ext_cant_disable[KVM_RISCV_ISA_EXT_MAX]; + bool filter_reg(__u64 reg) { switch (reg & ~REG_MASK) { @@ -48,6 +50,15 @@ bool filter_reg(__u64 reg) case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIFENCEI: case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIHPM: return true; + /* AIA registers are always available when Ssaia can't be disabled */ + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(siselect): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio1): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio2): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(sieh): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(siph): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio1h): + case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio2h): + return isa_ext_cant_disable[KVM_RISCV_ISA_EXT_SSAIA]; default: break; } @@ -71,14 +82,22 @@ static inline bool vcpu_has_ext(struct kvm_vcpu *vcpu, int ext)
void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c) { + unsigned long isa_ext_state[KVM_RISCV_ISA_EXT_MAX] = { 0 }; struct vcpu_reg_sublist *s; + int rc; + + for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) + __vcpu_get_reg(vcpu, RISCV_ISA_EXT_REG(i), &isa_ext_state[i]);
/* * Disable all extensions which were enabled by default * if they were available in the risc-v host. */ - for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) - __vcpu_set_reg(vcpu, RISCV_ISA_EXT_REG(i), 0); + for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) { + rc = __vcpu_set_reg(vcpu, RISCV_ISA_EXT_REG(i), 0); + if (rc && isa_ext_state[i]) + isa_ext_cant_disable[i] = true; + }
for_each_sublist(c, s) { if (!s->feature)
On Wed, Sep 20, 2023 at 09:16:08PM +0530, Anup Patel wrote:
Currently the AIA ONE_REG registers are reported by get-reg-list as new registers for various vcpu_reg_list configs whenever Ssaia is available on the host because Ssaia extension can only be disabled by Smstateen extension which is not always available.
To tackle this, we should filter-out AIA ONE_REG registers only when Ssaia can't be disabled for a VCPU.
Fixes: 477069398ed6 ("KVM: riscv: selftests: Add get-reg-list test") Signed-off-by: Anup Patel apatel@ventanamicro.com Reviewed-by: Atish Patra atishp@rivosinc.com
I guess you missed my reply to myself where I corrected my analysis and gave an r-b. Anyway, here it is again, and thanks for fixing up the nits.
Reviewed-by: Andrew Jones ajones@ventanamicro.com
Thanks, drew
On Wed, Sep 20, 2023 at 9:16 PM Anup Patel apatel@ventanamicro.com wrote:
This series includes few assorted fixes for KVM RISC-V ONE_REG interface and KVM_GET_REG_LIST API.
These patches can also be found in riscv_kvm_onereg_fixes_v2 branch at: https://github.com/avpatel/linux.git
Changes since v1:
- Addressed Drew's comments in PATCH4
Anup Patel (4): RISC-V: KVM: Fix KVM_GET_REG_LIST API for ISA_EXT registers RISC-V: KVM: Fix riscv_vcpu_get_isa_ext_single() for missing extensions KVM: riscv: selftests: Fix ISA_EXT register handling in get-reg-list KVM: riscv: selftests: Selectively filter-out AIA registers
Queued this series for 6.6-rcX fixes
Thanks, Anup
arch/riscv/kvm/vcpu_onereg.c | 7 ++- .../selftests/kvm/riscv/get-reg-list.c | 58 ++++++++++++++----- 2 files changed, 47 insertions(+), 18 deletions(-)
-- 2.34.1
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