From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59C61C433EF for ; Mon, 4 Apr 2022 12:36:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346258AbiDDMic (ORCPT ); Mon, 4 Apr 2022 08:38:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239289AbiDDMib (ORCPT ); Mon, 4 Apr 2022 08:38:31 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BBBA3275C0 for ; Mon, 4 Apr 2022 05:36:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1649075794; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=6ucG7CKhOXQxhd9YVn++2bq+OejY6acD5Dyyxst5dGg=; b=V0MFfFlZFhU7OViRG9m/sr+LsF/gjaETcHuFR4Pdoi9jux/MEtI7dlZcLEdlVZSmk14hDT 31A4EgV+umUj2zv+WbSEeXyqtQ42rLc1uQBXoJjq49dCt+iPxC6ziLg/bybzZs4FVCL/5m S3NE3Ys/4qI3kA4KoGacvVzpD+gj3Eo= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-593-thtjbbwsMt-w-P79D7DVKg-1; Mon, 04 Apr 2022 08:36:33 -0400 X-MC-Unique: thtjbbwsMt-w-P79D7DVKg-1 Received: by mail-ed1-f71.google.com with SMTP id l24-20020a056402231800b00410f19a3103so5424908eda.5 for ; Mon, 04 Apr 2022 05:36:33 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=6ucG7CKhOXQxhd9YVn++2bq+OejY6acD5Dyyxst5dGg=; b=IB87QaRF7mv0EPlANXqW1OpQFXV0VN2s7l16t5epeZ56iP/c0xAIhk716RoNLfHaqE gnimSWTIHd8UOM7romsScr8Ac06FHXHlnyxT7w86eAhgYiDDEHJE69J4VQTb9uTjb9UG 8oAG2ggC/j5CjdRBVavUOCFsCFsCX7iL830jwTc2M2ED/yGBLBbHDTmgsXx2tLVAX+W3 kDLUIOgPg4Nsq0llXkIVjzJ69lRBg0SaEsfVptaqrRIvpVmEFXI99mnERLAizX6sF3lx mzq3dMJVFE7w/OBXvivzlL0ZrPoKa8in3xQlwWaT3fjaCCHzmVAKQUN46dFzN1yhrB+8 wtKA== X-Gm-Message-State: AOAM532y4QR6eow1E2T+fiwuKbO/P2Lg54lgt8KsgY4PvOpPt3Z5/W5Q XcsG4BtdfZA4XemTrW4nLRZ8LgnlEzGvKGBDlZ/drTtfb07MV5YB7MO7kaW0Pmb4TSY1wcvC8Al N54LIBzP2a2N1 X-Received: by 2002:a17:907:1c0c:b0:6e0:9b15:29d5 with SMTP id nc12-20020a1709071c0c00b006e09b1529d5mr10634350ejc.416.1649075792269; Mon, 04 Apr 2022 05:36:32 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwBVgZGAP9kwOrKgPKmdYoXUYdAhAi8KcPiRzFFkpzMWCfiGq0LrsHtUDxUgPiCN3aEpYZIXQ== X-Received: by 2002:a17:907:1c0c:b0:6e0:9b15:29d5 with SMTP id nc12-20020a1709071c0c00b006e09b1529d5mr10634335ejc.416.1649075792087; Mon, 04 Apr 2022 05:36:32 -0700 (PDT) Received: from localhost (nat-pool-brq-t.redhat.com. [213.175.37.10]) by smtp.gmail.com with ESMTPSA id a5-20020aa7cf05000000b0041919e52a38sm5269738edy.46.2022.04.04.05.36.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 Apr 2022 05:36:31 -0700 (PDT) Date: Mon, 4 Apr 2022 14:36:30 +0200 From: Igor Mammedov To: "Kallol Biswas [C]" Cc: "kvm@vger.kernel.org" , lersek@redhat.com Subject: Re: General KVM/QEMU VM debugging techniques Message-ID: <20220404143630.02992ea4@redhat.com> In-Reply-To: References: X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Fri, 1 Apr 2022 23:50:16 +0000 "Kallol Biswas [C]" wrote: > Hi, > =C2=A0=C2=A0=C2=A0 We are observing a problem with CPU hotplug. >=20 > If secureboot option is enabled under UEFI =C2=A0and then if we try to do= CPU hotplug the VM crashes/just reboots. >=20 > No crash dump is generated, no panic message, just VM restarts. Issue see= ms like:=20 > https://bugzilla.redhat.com/show_bug.cgi?id=3D1834250 CPU hotplug with SMM (for q35) was merged in QEMU-5.2 and unplug part in 6.0, you also need a matching OVMF build to make it work. Later upto 6.2 (included) there were minor fixes dealing with incorrect configs. > What are the debugging techniques we can apply to halt the VM and examine= what's going on? > VM has been configured with crash dump. I'd start with https://www.linux-kvm.org/page/Tracing to find out when it goes south. > Nucleodyne at Nutanix > 408-718-8164 >=20