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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C246C433DF for ; Mon, 19 Oct 2020 08:58:54 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D47ED2053B for ; Mon, 19 Oct 2020 08:58:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QvuBbFz1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D47ED2053B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:42152 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kUR0G-0004vm-Qw for qemu-devel@archiver.kernel.org; Mon, 19 Oct 2020 04:58:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40288) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kUQym-0003nw-V2 for qemu-devel@nongnu.org; Mon, 19 Oct 2020 04:57:20 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:46570) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kUQyi-0004cO-8x for qemu-devel@nongnu.org; Mon, 19 Oct 2020 04:57:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603097834; 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; 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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/19 01:44:30 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, Stefan Hajnoczi , Markus Armbruster Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 17.10.2020 um 10:15 hat Volker Rümelin geschrieben: > > From: Kevin Wolf > > > > This moves the QMP dispatcher to a coroutine and runs all QMP command > > handlers that declare 'coroutine': true in coroutine context so they > > can avoid blocking the main loop while doing I/O or waiting for other > > events. > > > > For commands that are not declared safe to run in a coroutine, the > > dispatcher drops out of coroutine context by calling the QMP command > > handler from a bottom half. > > Hi Kevin, > > since commit 9ce44e2ce2 "qmp: Move dispatcher to a coroutine" I see > the following error on Windows whenever I close the QEMU window or > shut down the guest. > > $ ./qemu-system-x86_64.exe -machine pc,accel=tcg -display gtk > ** > ERROR:../qemu/util/aio-win32.c:337:aio_poll: assertion failed: (in_aio_context_home_thread(ctx)) > Bail out! ERROR:../qemu/util/aio-win32.c:337:aio_poll: assertion failed: (in_aio_context_home_thread(ctx)) > > I wonder if you forgot to apply the changes to util/aio-posix.c to > util/aio-win32.c too? This solves the problem on my Windows host. But > I have to admit I don't know the code here. Hi Volker, yes, you're right. The assertion in the Windows code was added only in commit 5710a3e09f9 after I had posted some versions of the patch series, so while I did check this initially, I missed during the rebase for later versions of the series that I would have to update the patches for Windows. Would you like to send a patch for this? I could send one myself if you prefer, but I can only compile-test Windows patches, so I'd have to rely on your testing anyway. Kevin > > diff --git a/util/aio-posix.c b/util/aio-posix.c > > index 280f27bb99..30f5354b1e 100644 > > --- a/util/aio-posix.c > > +++ b/util/aio-posix.c > > @@ -15,6 +15,7 @@ > > > > #include "qemu/osdep.h" > > #include "block/block.h" > > +#include "qemu/main-loop.h" > > #include "qemu/rcu.h" > > #include "qemu/rcu_queue.h" > > #include "qemu/sockets.h" > > @@ -558,8 +559,13 @@ bool aio_poll(AioContext *ctx, bool blocking) > > * There cannot be two concurrent aio_poll calls for the same AioContext (or > > * an aio_poll concurrent with a GSource prepare/check/dispatch callback). > > * We rely on this below to avoid slow locked accesses to ctx->notify_me. > > + * > > + * aio_poll() may only be called in the AioContext's thread. iohandler_ctx > > + * is special in that it runs in the main thread, but that thread's context > > + * is qemu_aio_context. > > */ > > - assert(in_aio_context_home_thread(ctx)); > > + assert(in_aio_context_home_thread(ctx == iohandler_get_aio_context() ? > > + qemu_get_aio_context() : ctx)); > > > > qemu_lockcnt_inc(&ctx->list_lock); > > >