Re: [PATCH v7 36/45] arm64: RME: Set breakpoint parameters through SET_ONE_REG

Gavin Shan
2025-03-04T23:46:54Z

On 2/14/25 2:14 AM, Steven Price wrote:
> From: Jean-Philippe Brucker <jean-philippe@linaro.org>
>
> Allow userspace to configure the number of breakpoints and watchpoints
> of a Realm VM through KVM_SET_ONE_REG ID_AA64DFR0_EL1.
>
> The KVM sys_reg handler checks the user value against the maximum value
> given by RMM (arm64_check_features() gets it from the
> read_sanitised_id_aa64dfr0_el1() reset handler).
>
> Userspace discovers that it can write these fields by issuing a
> KVM_ARM_GET_REG_WRITABLE_MASKS ioctl.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Signed-off-by: Steven Price <steven.price@arm.com>
> ---
> arch/arm64/kvm/guest.c | 2 ++
> arch/arm64/kvm/rme.c | 3 +++
> arch/arm64/kvm/sys_regs.c | 17 +++++++++++------
> 3 files changed, 16 insertions(+), 6 deletions(-)
>

Reviewed-by: Gavin Shan <gshan@redhat.com>