From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:57950) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tv2oQ-0002Xw-QO for qemu-devel@nongnu.org; Tue, 15 Jan 2013 04:28:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tv2oM-0000dC-2v for qemu-devel@nongnu.org; Tue, 15 Jan 2013 04:28:06 -0500 Received: from cantor2.suse.de ([195.135.220.15]:41030 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tv2oL-0000d3-Qy for qemu-devel@nongnu.org; Tue, 15 Jan 2013 04:28:02 -0500 From: =?UTF-8?q?Andreas=20F=C3=A4rber?= Date: Tue, 15 Jan 2013 10:27:27 +0100 Message-Id: <1358242058-1404-10-git-send-email-afaerber@suse.de> In-Reply-To: <1358242058-1404-1-git-send-email-afaerber@suse.de> References: <1358242058-1404-1-git-send-email-afaerber@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH 09/20] target-i386: Disable kvm_mmu by default List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Eduardo Habkost , =?UTF-8?q?Andreas=20F=C3=A4rber?= From: Eduardo Habkost KVM_CAP_PV_MMU capability reporting was removed from the kernel since v2.6.33 (see commit a68a6a7282373), and was completely removed from the kernel since v3.3 (see commit fb92045843). It doesn't make sense to keep it enabled by default, as it would cause unnecessary hassle when using the "enforce" flag. This disables kvm_mmu on all machine-types. With this fix, the possible scenarios when migrating from QEMU <=3D 1.3 to QEMU 1.4 are: ------------+----------+-------------------------------------------------= --- src kernel | dst kern.| Result ------------+----------+-------------------------------------------------= --- >=3D 2.6.33 | any | kvm_mmu was already disabled and will stay dis= abled <=3D 2.6.32 | >=3D 3.3 | correct live migration is impossible <=3D 2.6.32 | <=3D 3.2 | kvm_mmu will be disabled on next guest reboo= t * ------------+----------+-------------------------------------------------= --- * If they are running kernel <=3D 2.6.32 and want kvm_mmu to be kept enabled on guest reboot, they can explicitly add +kvm_mmu to the QEMU command-line. Using 2.6.33 and higher, it is not possible to enable kvm_mmu explicitly anymore. Signed-off-by: Eduardo Habkost Reviewed-by: Gleb Natapov Signed-off-by: Andreas F=C3=A4rber --- target-i386/cpu.c | 1 - 1 Datei ge=C3=A4ndert, 1 Zeile entfernt(-) diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 992b614..cb385fb 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -159,7 +159,6 @@ int enforce_cpuid =3D 0; #if defined(CONFIG_KVM) static uint32_t kvm_default_features =3D (1 << KVM_FEATURE_CLOCKSOURCE) = | (1 << KVM_FEATURE_NOP_IO_DELAY) | - (1 << KVM_FEATURE_MMU_OP) | (1 << KVM_FEATURE_CLOCKSOURCE2) | (1 << KVM_FEATURE_ASYNC_PF) | (1 << KVM_FEATURE_STEAL_TIME) | --=20 1.7.10.4