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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id D48E0CF11C3 for ; Thu, 10 Oct 2024 10:20:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1syqHD-0006LI-00; Thu, 10 Oct 2024 06:20:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1syqHB-0006K2-ED for qemu-devel@nongnu.org; Thu, 10 Oct 2024 06:20:09 -0400 Received: from mail-qt1-x833.google.com ([2607:f8b0:4864:20::833]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1syqH8-0003Tg-LK for qemu-devel@nongnu.org; Thu, 10 Oct 2024 06:20:09 -0400 Received: by mail-qt1-x833.google.com with SMTP id d75a77b69052e-46041d86566so3376201cf.3 for ; Thu, 10 Oct 2024 03:20:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728555605; x=1729160405; darn=nongnu.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=/2k0y3LaJZ+N4GOiZeGr18q3sGaDuASYM4iLUC6otDk=; b=WDa1n9a+DeSpv3rj8u3fQqr8oiL0BAIJ1yek0GvrDZ0Ka2BYQCCE0Mi2i3gJ4LvZ4H WC++PcW0PNY9kVH1CCBUP9xGSoTGFfuNgrRTy2L5IC6MTsySkPDGSCIzznKAEUjvEvh/ ad224ajtjx+KsLA8Rs7uN1rEeAybbfi1sICzXQHrUsk+E3SdW4HmAjbURHNKuoowB55u HYsNRPYk9796xESZwCch4oW11djAoX7nfsVLaX9jZPRcm8vdbePTFEDApdQ+ilAVr8+m Qn9FgWTsIm/Jq4w6oSCShWHpKTPWuKGfvVetTcl+MWZXvTMzPTOdLza2eP1iO870f8E2 lcog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728555605; x=1729160405; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=/2k0y3LaJZ+N4GOiZeGr18q3sGaDuASYM4iLUC6otDk=; b=HAwvluZpOySsrBiXxb52Q8jlg+hEkXoBMWRB33GYBvPeAsdqmL5eycSLSWuXpeGIZn XZXLkNuqn3IAMX9tRRR5yeOmZD3h+UaaZjUMXO3zDH7irFXZcaIdlvdwtYKI0qBWdJyG khV58AwYDuAxR6SoqD9twQkkZXQZlkIXirL/8XjWNXofw/RmgCD8pEt5LpXweiYoNOPX E4MHuuWIWuHnndD7mT4N/gRdutTrvjxWFOVPKHmRQkQIMCxdNM9leh5ZRXWVLPdr1RG/ JOscxHMnV3yUEBPHvZ4wCVRoG84jo5qbuQglF+HErNKtr2UD+yKe9BcVmg5/YrWHYDXI jG/g== X-Gm-Message-State: AOJu0YxN6XV36gCZULgeVIM+X+87ICfKLKRwBBm9UAVnoBLEM2FaiZDQ V1KI26OtkoCBGWSQTnDsqo1WnVTgmMCixZwoM8JUgWIXHq/jaSsh7gf9ZbmiDoOWdlZHjo82uO5 R9RK2XhQucRh5lZYyxfHeBIOdFhU= X-Google-Smtp-Source: AGHT+IHh6uuIsXVYjEOyQMnFeuxjMaAM7e8f1rnS7ugUa5XhimDMYEzcwN2+ja3PdmDrFvjGydc6eOwsDQ861dO9+Zc= X-Received: by 2002:a05:622a:528d:b0:45d:9689:9de4 with SMTP id d75a77b69052e-45fb0e53552mr78433381cf.43.1728555605154; Thu, 10 Oct 2024 03:20:05 -0700 (PDT) MIME-Version: 1.0 References: <20241010092619.323489-1-r.peniaev@gmail.com> In-Reply-To: <20241010092619.323489-1-r.peniaev@gmail.com> From: =?UTF-8?B?TWFyYy1BbmRyw6kgTHVyZWF1?= Date: Thu, 10 Oct 2024 14:19:53 +0400 Message-ID: Subject: Re: [PATCH 1/1] chardev/char: fix qemu_chr_is_busy() check To: Roman Penyaev Cc: qemu-devel@nongnu.org Content-Type: multipart/alternative; boundary="000000000000d1e29506241cb6e5" Received-SPF: pass client-ip=2607:f8b0:4864:20::833; envelope-from=marcandre.lureau@gmail.com; helo=mail-qt1-x833.google.com 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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org --000000000000d1e29506241cb6e5 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Roman On Thu, Oct 10, 2024 at 1:28=E2=80=AFPM Roman Penyaev = wrote: > `mux_cnt` struct member never goes negative or decrements, > so mux chardev can be !busy only when there are no > frontends attached. This patch fixes the always-true > check. > > Fixes: a4afa548fc6d ("char: move front end handlers in CharBackend") > Signed-off-by: Roman Penyaev > Cc: "Marc-Andr=C3=A9 Lureau" > Cc: qemu-devel@nongnu.org Reviewed-by: Marc-Andr=C3=A9 Lureau That would be worth some new tests for chardev removal. It seems to be lacking. And mux probably need extra fixing. I can take a look if you don't= . thanks > --- > chardev/char.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/chardev/char.c b/chardev/char.c > index c0cc52824b48..f54dc3a86286 100644 > --- a/chardev/char.c > +++ b/chardev/char.c > @@ -333,7 +333,7 @@ static bool qemu_chr_is_busy(Chardev *s) > { > if (CHARDEV_IS_MUX(s)) { > MuxChardev *d =3D MUX_CHARDEV(s); > - return d->mux_cnt >=3D 0; > + return d->mux_cnt > 0; > } else { > return s->be !=3D NULL; > } > -- > 2.34.1 > > > --=20 Marc-Andr=C3=A9 Lureau --000000000000d1e29506241cb6e5 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Roman

On Thu, Oct 10, 2024 at 1:28= =E2=80=AFPM Roman Penyaev <r.peni= aev@gmail.com> wrote:
`mux_cnt` struct member never goes negative or decrements,
so mux chardev can be !busy only when there are no
frontends attached. This patch fixes the always-true
check.

Fixes: a4afa548fc6d ("char: move front end handlers in CharBackend&quo= t;)
Signed-off-by: Roman Penyaev <r.peniaev@gmail.com>
Cc: "Marc-Andr=C3=A9 Lureau" <marcandre.lureau@redhat.com>
Cc: qemu-devel@n= ongnu.org

Reviewed-by: Marc-Andr=C3=A9 = Lureau <marcandre.lureau@= redhat.com>

That would be worth some new te= sts for chardev removal. It seems to be lacking. And mux probably need extr= a fixing. I can take a look if you don't.

than= ks


--
Marc-Andr=C3= =A9 Lureau
--000000000000d1e29506241cb6e5--