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 60DC1C61DA4 for ; Mon, 6 Mar 2023 21:03:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229901AbjCFVDM (ORCPT ); Mon, 6 Mar 2023 16:03:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229524AbjCFVDL (ORCPT ); Mon, 6 Mar 2023 16:03:11 -0500 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE5702A6CB for ; Mon, 6 Mar 2023 13:03:07 -0800 (PST) Received: by mail-pf1-x44a.google.com with SMTP id h14-20020aa786ce000000b005a89856900eso6061702pfo.14 for ; Mon, 06 Mar 2023 13:03:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1678136587; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Ox5t39D8exC5MlTd4JKWoX/S1r8DXoScCVAm6FqL7rY=; b=C73M/Vr/LvBWIy2A4y6akc9ekZE1IzX0hS9k6ydmmcw1pBIQnX3oMOqM08l+vhdubI W/klV34mIMX5MMQkFvzY7Nn9YzHeM1iQgoeTSGDI1mN81Yt5pvweGh+dcr87gRJBFrig UL2VkP1MMvFWWqkeBEHHcHGLaLSurWflL4sbArBXtYjS98PZMzHEy+/4En5hxRxD2gBI 8wuPO6vindgIyAG7yoVWkuDRp9XD16JUHlo3RbYu7J7Q+BRKJSB6wo9k5dixU91MIoat 2jCD03fKpTjZx4fyca8yzhTF2Ps9Otj8v/vZkeSL804mXmENb1ezkNtYHesnub9S1I0Q VgsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678136587; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Ox5t39D8exC5MlTd4JKWoX/S1r8DXoScCVAm6FqL7rY=; b=m6SHX053Z0oe+rX+nykvmzvC6ju9uug1yPy/MQAo2NcNaUQ9G6sGOIXeA7ruQDFVCq bdI2dWxaDDegoB75lnncJDJooxIBDewH705xrxbAUnacEzQdbSM81Q/aVwZ0xRWDk/Cb oq2ecwIiHlA5JvjlTKu2cs99OHIzkjCbqFWO6JgXkjmGCDgjORTy1/ikDtgD9nBmwOwD GBTB0VUv8PJQKuS8HEljMMpXvzEoetfer3CxKq3HHgjVyF3VpCoWCTZfe4mqGfsfw/0q fQl88oCISLai2QGFr4nskFjzh8nYjul7YzfBJ66mzP2pXC+gJydkO2Zsm0JHh77ylbLR FMMQ== X-Gm-Message-State: AO0yUKX2j0jyiqOgT/cU6QiB1D1X7FXULBJ3xGiQMAQEpLCZDY8m88js l2GJCqGi2H/G3e3+E6vDu72vU9rD1d4= X-Google-Smtp-Source: AK7set9hIxIkU3escohvWsYYYndDS+3klnxI0ZZaiw7LXTPm2s7ZFZRivFThSsQGycmto2kn0atbZTJEmAc= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:903:2c1:b0:19a:5953:e85a with SMTP id s1-20020a17090302c100b0019a5953e85amr4854488plk.2.1678136587513; Mon, 06 Mar 2023 13:03:07 -0800 (PST) Date: Mon, 6 Mar 2023 13:03:06 -0800 In-Reply-To: <000b01d94b66$4be1d8e0$e3a58aa0$@fastmail.fm> Mime-Version: 1.0 References: <000b01d94b66$4be1d8e0$e3a58aa0$@fastmail.fm> Message-ID: Subject: Re: QUESTION: INT1 instruction for breakpoints From: Sean Christopherson To: billz@fastmail.fm Cc: kvm@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Feb 28, 2023, billz@fastmail.fm wrote: > Is it possible to use the INT1 (instead of INT3) instruction for breakpoints > under KVM? It does not seem that this instruction causes a KVM_EXIT_DEBUG (or > any other exit) and it is silently skipped instead. > > If it is possible, how should I configure the KVM API to receive such exits? #DBs from INT1, a.k.a. ICEBP, should be forwarded to userspace if KVM_GUESTDBG_USE_HW_BP is set.