From 53a049d7d78e5ccf6d4c0d7b0edb18f8b999df94 Mon Sep 17 00:00:00 2001 From: Wainer dos Santos Moschetta Date: Mon, 16 Dec 2019 16:14:36 -0300 Subject: [PATCH] python/qemu: accel: Strengthen kvm_available() checks MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently kvm_available() checks for the presence of kvm module and, if target and host arches don't mismatch. This patch adds an 3rd checking: if QEMU binary was compiled with kvm support. Signed-off-by: Wainer dos Santos Moschetta Reviewed-by: Alex Bennée Reviewed-by: Cleber Rosa Reviewed-by: Philippe Mathieu-Daudé Tested-by: Cleber Rosa Message-Id: <20191216191438.93418-4-wainersm@redhat.com> Signed-off-by: Cleber Rosa --- python/qemu/accel.py | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/python/qemu/accel.py b/python/qemu/accel.py index 7395cee793..5fce3aa3dd 100644 --- a/python/qemu/accel.py +++ b/python/qemu/accel.py @@ -46,9 +46,24 @@ def list_accel(qemu_bin): # Skip the first line which is the header. return [acc.strip() for acc in out.splitlines()[1:]] -def kvm_available(target_arch=None): - host_arch = os.uname()[4] - if target_arch and target_arch != host_arch: - if target_arch != ADDITIONAL_ARCHES.get(host_arch): - return False - return os.access("/dev/kvm", os.R_OK | os.W_OK) +def kvm_available(target_arch=None, qemu_bin=None): + """ + Check if KVM is available using the following heuristic: + - Kernel module is present in the host; + - Target and host arches don't mismatch; + - KVM is enabled in the QEMU binary. + + @param target_arch (str): target architecture + @param qemu_bin (str): path to the QEMU binary + @return True if kvm is available, otherwise False. + """ + if not os.access("/dev/kvm", os.R_OK | os.W_OK): + return False + if target_arch: + host_arch = os.uname()[4] + if target_arch != host_arch: + if target_arch != ADDITIONAL_ARCHES.get(host_arch): + return False + if qemu_bin and "kvm" not in list_accel(qemu_bin): + return False + return True