From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48231) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eIED9-0008OC-HF for qemu-devel@nongnu.org; Fri, 24 Nov 2017 08:40:10 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eIED0-0000Ks-2r for qemu-devel@nongnu.org; Fri, 24 Nov 2017 08:40:07 -0500 References: <1511530238-18318-1-git-send-email-eric.auger@redhat.com> <1511530238-18318-3-git-send-email-eric.auger@redhat.com> From: Auger Eric Message-ID: <0a83e699-1985-3720-b5db-14c29c629a67@redhat.com> Date: Fri, 24 Nov 2017 14:39:44 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v4 2/4] hw/intc/arm_gicv3_its: Implement a minimalist reset List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: eric.auger.pro@gmail.com, qemu-arm , QEMU Developers , wanghaibin.wang@huawei.com, Vijay Kilari , Andrew Jones , Wei Huang , Juan Quintela , "Dr. David Alan Gilbert" , Christoffer Dall , wu.wubin@huawei.com Hi Peter, On 24/11/17 14:34, Peter Maydell wrote: > On 24 November 2017 at 13:30, Eric Auger wrote: >> At the moment the ITS is not properly reset and this causes >> various bugs on save/restore. We implement a minimalist reset >> through individual register writes but for kernel versions >> before v4.15 this fails voiding the vITS cache. We cannot >> claim we have a comprehensive reset (hence the error message) >> but that's better than nothing. >> >> Signed-off-by: Eric Auger >> >> --- >> >> v2 -> v3: >> - individual register writes performed in kvm_arm_its_reset >> - check KVM_DEV_ARM_VGIC_GRP_ITS_REGS support >> --- >> hw/intc/arm_gicv3_its_kvm.c | 41 +++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 41 insertions(+) >> >> diff --git a/hw/intc/arm_gicv3_its_kvm.c b/hw/intc/arm_gicv3_its_kvm.c >> index b1b322b..83e5268 100644 >> --- a/hw/intc/arm_gicv3_its_kvm.c >> +++ b/hw/intc/arm_gicv3_its_kvm.c >> @@ -28,6 +28,16 @@ >> >> #define TYPE_KVM_ARM_ITS "arm-its-kvm" >> #define KVM_ARM_ITS(obj) OBJECT_CHECK(GICv3ITSState, (obj), TYPE_KVM_ARM_ITS) >> +#define KVM_ARM_ITS_CLASS(klass) \ >> + OBJECT_CLASS_CHECK(KVMARMITSClass, (klass), TYPE_KVM_ARM_ITS) >> +#define KVM_ARM_ITS_GET_CLASS(obj) \ >> + OBJECT_GET_CLASS(KVMARMITSClass, (obj), TYPE_KVM_ARM_ITS) >> + >> +typedef struct KVMARMITSClass { >> + GICv3ITSCommonClass parent_class; >> + void (*parent_reset)(DeviceState *dev); >> +} KVMARMITSClass; >> + >> >> static int kvm_its_send_msi(GICv3ITSState *s, uint32_t value, uint16_t devid) >> { >> @@ -186,6 +196,34 @@ static void kvm_arm_its_post_load(GICv3ITSState *s) >> GITS_CTLR, &s->ctlr, true, &error_abort); >> } >> >> +static void kvm_arm_its_reset(DeviceState *dev) >> +{ >> + GICv3ITSState *s = ARM_GICV3_ITS_COMMON(dev); >> + KVMARMITSClass *c = KVM_ARM_ITS_GET_CLASS(s); >> + int i; >> + >> + c->parent_reset(dev); >> + >> + error_report("ITS KVM: full reset is not supported by the host kernel"); > > This message claims that we have a problem because of the host > kernel version, but I can't see where we do the check on the > host kernel that lets us avoid the error message when it's > new enough ? Actually the check is added in 4/4. So in that patch the message may be "full ITS reset is not supported" without mentioning the host kernel. Thanks Eric > > thanks > -- PMM >