On Fri, Apr 25, 2025 at 01:02:02PM -0300, Daniel Henrique Barboza wrote: > We want to support scounteren as a KVM CSR. The KVM UAPI defines every > CSR size as target_ulong, and our env->scounteren is fixed at 32 bits. > > The other existing cases where the property size does not match the KVM > reg size happens with uint64_t properties, like 'mstatus'. When running > a 32 bit CPU we'll write a 32 bit 'sstatus' KVM reg into the 64 bit > 'mstatus' field. As long as we're consistent, i.e. we're always > reading/writing the same words, this is ok. > > For scounteren, a KVM guest running in a 64 bit CPU will end up writing > a 64 bit reg in a 32 bit field. This will have all sort of funny side > effects in the KVM guest that we would rather avoid. > > Increase scounteren to target_ulong to allow KVM to read/write the > scounteren CSR without any surprises. > > Aside from bumping the version of the RISCVCPU vmstate no other > behavioral changes are expected. > > Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com> > --- > target/riscv/cpu.h | 9 ++++++++- > target/riscv/machine.c | 6 +++--- > 2 files changed, 11 insertions(+), 4 deletions(-) >
Reviewed-by: Andrew Jones <ajo...@ventanamicro.com>
