KVM_REG_RISCV_FP_F regs have u32 size according to the API, but by using
kvm_riscv_reg_id() in RISCV_FP_F_REG() we're returning u64 sizes when
running with TARGET_RISCV64. The most likely reason why no one noticed
this is because we're not implementing kvm_cpu_synchronize_state() in
RISC-V yet.

Create a new helper that returns a KVM ID with u32 size and use it in
RISCV_FP_F_REG().

Reported-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
---
 target/riscv/kvm/kvm-cpu.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
index 45b6cf1cfa..9bfbc4ac98 100644
--- a/target/riscv/kvm/kvm-cpu.c
+++ b/target/riscv/kvm/kvm-cpu.c
@@ -72,6 +72,11 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type,
     return id;
 }
 
+static uint64_t kvm_riscv_reg_id_u32(uint64_t type, uint64_t idx)
+{
+    return KVM_REG_RISCV | KVM_REG_SIZE_U32 | type | idx;
+}
+
 #define RISCV_CORE_REG(env, name)  kvm_riscv_reg_id(env, KVM_REG_RISCV_CORE, \
                  KVM_REG_RISCV_CORE_REG(name))
 
@@ -81,7 +86,7 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type,
 #define RISCV_TIMER_REG(env, name)  kvm_riscv_reg_id(env, KVM_REG_RISCV_TIMER, \
                  KVM_REG_RISCV_TIMER_REG(name))
 
-#define RISCV_FP_F_REG(env, idx)  kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_F, idx)
+#define RISCV_FP_F_REG(idx)  kvm_riscv_reg_id_u32(KVM_REG_RISCV_FP_F, idx)
 
 #define RISCV_FP_D_REG(env, idx)  kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_D, idx)
 
@@ -586,7 +591,7 @@ static int kvm_riscv_get_regs_fp(CPUState *cs)
     if (riscv_has_ext(env, RVF)) {
         uint32_t reg;
         for (i = 0; i < 32; i++) {
-            ret = kvm_get_one_reg(cs, RISCV_FP_F_REG(env, i), &reg);
+            ret = kvm_get_one_reg(cs, RISCV_FP_F_REG(i), &reg);
             if (ret) {
                 return ret;
             }
@@ -620,7 +625,7 @@ static int kvm_riscv_put_regs_fp(CPUState *cs)
         uint32_t reg;
         for (i = 0; i < 32; i++) {
             reg = env->fpr[i];
-            ret = kvm_set_one_reg(cs, RISCV_FP_F_REG(env, i), &reg);
+            ret = kvm_set_one_reg(cs, RISCV_FP_F_REG(i), &reg);
             if (ret) {
                 return ret;
             }
-- 
2.41.0

On Fri, Dec 08, 2023 at 03:38:31PM -0300, Daniel Henrique Barboza wrote:
> KVM_REG_RISCV_FP_F regs have u32 size according to the API, but by using
> kvm_riscv_reg_id() in RISCV_FP_F_REG() we're returning u64 sizes when
> running with TARGET_RISCV64. The most likely reason why no one noticed
> this is because we're not implementing kvm_cpu_synchronize_state() in
> RISC-V yet.
> 
> Create a new helper that returns a KVM ID with u32 size and use it in
> RISCV_FP_F_REG().
> 
> Reported-by: Andrew Jones <ajones@ventanamicro.com>
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>  target/riscv/kvm/kvm-cpu.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
> index 45b6cf1cfa..9bfbc4ac98 100644
> --- a/target/riscv/kvm/kvm-cpu.c
> +++ b/target/riscv/kvm/kvm-cpu.c
> @@ -72,6 +72,11 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type,
>      return id;
>  }
>  
> +static uint64_t kvm_riscv_reg_id_u32(uint64_t type, uint64_t idx)
> +{
> +    return KVM_REG_RISCV | KVM_REG_SIZE_U32 | type | idx;
> +}
> +
>  #define RISCV_CORE_REG(env, name)  kvm_riscv_reg_id(env, KVM_REG_RISCV_CORE, \
>                   KVM_REG_RISCV_CORE_REG(name))
>  
> @@ -81,7 +86,7 @@ static uint64_t kvm_riscv_reg_id(CPURISCVState *env, uint64_t type,
>  #define RISCV_TIMER_REG(env, name)  kvm_riscv_reg_id(env, KVM_REG_RISCV_TIMER, \
>                   KVM_REG_RISCV_TIMER_REG(name))
>  
> -#define RISCV_FP_F_REG(env, idx)  kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_F, idx)
> +#define RISCV_FP_F_REG(idx)  kvm_riscv_reg_id_u32(KVM_REG_RISCV_FP_F, idx)
>  
>  #define RISCV_FP_D_REG(env, idx)  kvm_riscv_reg_id(env, KVM_REG_RISCV_FP_D, idx)
>  
> @@ -586,7 +591,7 @@ static int kvm_riscv_get_regs_fp(CPUState *cs)
>      if (riscv_has_ext(env, RVF)) {
>          uint32_t reg;
>          for (i = 0; i < 32; i++) {
> -            ret = kvm_get_one_reg(cs, RISCV_FP_F_REG(env, i), &reg);
> +            ret = kvm_get_one_reg(cs, RISCV_FP_F_REG(i), &reg);
>              if (ret) {
>                  return ret;
>              }
> @@ -620,7 +625,7 @@ static int kvm_riscv_put_regs_fp(CPUState *cs)
>          uint32_t reg;
>          for (i = 0; i < 32; i++) {
>              reg = env->fpr[i];
> -            ret = kvm_set_one_reg(cs, RISCV_FP_F_REG(env, i), &reg);
> +            ret = kvm_set_one_reg(cs, RISCV_FP_F_REG(i), &reg);
>              if (ret) {
>                  return ret;
>              }
> -- 
> 2.41.0
>

This patch looks good, so

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

But... I don't see where we save/restore __riscv_f_ext_state.fcsr

Thanks,
drew