From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fabiano Rosas Date: Wed, 20 Mar 2019 18:39:49 +0000 Subject: [RFC PATCH 0/1] KVM: PPC: Inform userspace about singlestep support Message-Id: <20190320183951.29537-1-farosas@linux.ibm.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: kvm-ppc@vger.kernel.org Cc: kvm@vger.kernel.org, rkrcmar@redhat.com, aik@ozlabs.ru, pbonzini@redhat.com, linuxppc-dev@lists.ozlabs.org, david@gibson.dropbear.id.au I am looking for a way to inform userspace about the lack of an implementation in KVM HV for single stepping of instructions (KVM_GUESTDGB_SINGLESTEP bit from SET_GUEST_DEBUG ioctl). This will be used by QEMU to decide whether to attempt a call to the set_guest_debug ioctl (for BookE, KVM PR) or fallback to a QEMU only implementation (for KVM HV). QEMU thread: http://patchwork.ozlabs.org/cover/1049811/ My current proposal is to introduce a ppc-specific capability for this. However I'm not sure if this would be better as a cap common for all architectures or even if it should report on all of the possible set_guest_debug flags to cover for the future. Please comment. Thanks. Fabiano Rosas (1): KVM: PPC: Report single stepping capability arch/powerpc/kvm/powerpc.c | 5 +++++ include/uapi/linux/kvm.h | 1 + 2 files changed, 6 insertions(+) -- 2.20.1