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=-7.8 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HTML_MESSAGE,INCLUDES_CR_TRAILER,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 DC2CEC07E96 for ; Thu, 8 Jul 2021 16:42:04 +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 3FA3461876 for ; Thu, 8 Jul 2021 16:42:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3FA3461876 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59566 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m1X6B-00021j-Cg for qemu-devel@archiver.kernel.org; Thu, 08 Jul 2021 12:42:03 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35948) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m1WUy-00051S-M2 for qemu-devel@nongnu.org; Thu, 08 Jul 2021 12:03:36 -0400 Received: from mail-ej1-x62f.google.com ([2a00:1450:4864:20::62f]:42804) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1m1WUu-0005c0-3D for qemu-devel@nongnu.org; Thu, 08 Jul 2021 12:03:36 -0400 Received: by mail-ej1-x62f.google.com with SMTP id bg14so10491911ejb.9 for ; Thu, 08 Jul 2021 09:03:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=7O6GkFO+drjFXaEQyjbNf2cHtY6N8qMbb7aagsR/+/g=; b=frKyxOxR17NdyXhGws6BXrwGM6v6PkE9jS9VIBwO66uyhgz0M0ucMEFUHxycTgxWF1 Wv5Ws7yfjQwl4QaLlvcxyDrTlOtpH8q5KqQ6NPXzPhksC8SQxmJT+pae2MJcns4t3x/W VD+zKpmX++clbIjY5fkPEEbCInOD4SXNl4yE0CEFuP0/l9CEEPFfdB+nj1dUYVw4Ie0R yt6A3I7DP1NUQg6mBQAO4j4+XwxuH1yDqrXXWWAKk1B3oR+CELyIfovLV2R2spWSsifl UweuMpEKNHxOZHt6SpNsNTker+hTJmlSL14p6hupmHVmyMCvUW8zvHWC6PFTK1A1AA2C KrFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=7O6GkFO+drjFXaEQyjbNf2cHtY6N8qMbb7aagsR/+/g=; b=emHm3Jnwp7/vnT/ncsNDEpmRX6wbaYQMIqJyU/LM6iPQKobCw4SfSWC1+0//0akFrD 66qHFVOXMNgx95bQDdcWMR/eNHuSw3qTOOe0c3inPGIRwVJ3ypPdTlJu8NU9WWJT/g+L hUVpi/eWntorVemor+Webcf+a2byg9YdObnv7xbqokrQsmCvpspqtZwhffM0JN5JIOPt YDcEpzlK5rmXt5DqRVzTWaWL3X+jyhP3VcJ7q14PU6ef7uhy9FWS2wxlaAAKclpfFTb5 b6VMKE2vIfG0CubtIF/6ZYaghekCJD3GlJ+oT0DtYKLio+tYFXRI6VFlrJdw3/U+owAA 0uxQ== X-Gm-Message-State: AOAM5302SagmrqZ/6HnBx75AGOd6fPkhGsnwg32NHCQFNYgXMqUSOvYv wQbLKFvEHH9gloT+4uaJVwY5FZSrtu0iQmtIJdE= X-Google-Smtp-Source: ABdhPJySZYkvf+3wDoOFjcsYkIIdYh0/FR2IfMDy3FWR0bqRdnTZG9S42uypUfjyplWKImm1l8oZIZwEnwRtxrzzOlU= X-Received: by 2002:a17:906:f751:: with SMTP id jp17mr8686433ejb.105.1625760210390; Thu, 08 Jul 2021 09:03:30 -0700 (PDT) MIME-Version: 1.0 References: <1625678434-240960-1-git-send-email-steven.sistare@oracle.com> <1625678434-240960-21-git-send-email-steven.sistare@oracle.com> In-Reply-To: <1625678434-240960-21-git-send-email-steven.sistare@oracle.com> From: =?UTF-8?B?TWFyYy1BbmRyw6kgTHVyZWF1?= Date: Thu, 8 Jul 2021 20:03:18 +0400 Message-ID: Subject: Re: [PATCH V5 20/25] chardev: cpr framework To: Steve Sistare Content-Type: multipart/alternative; boundary="000000000000d4926805c69ecba7" Received-SPF: pass client-ip=2a00:1450:4864:20::62f; envelope-from=marcandre.lureau@gmail.com; helo=mail-ej1-x62f.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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Zeng , Juan Quintela , Eric Blake , "Michael S. Tsirkin" , QEMU , "Dr. David Alan Gilbert" , Alex Williamson , Stefan Hajnoczi , Paolo Bonzini , "Daniel P. Berrange" , =?UTF-8?Q?Philippe_Mathieu=2DDaud=C3=A9?= , =?UTF-8?B?QWxleCBCZW5uw6ll?= , Markus Armbruster Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --000000000000d4926805c69ecba7 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi On Wed, Jul 7, 2021 at 9:37 PM Steve Sistare wrote: > Add QEMU_CHAR_FEATURE_CPR for devices that support cpr. > Add the chardev close_on_cpr option for devices that can be closed on cpr > and reopened after exec. > cpr is allowed only if either QEMU_CHAR_FEATURE_CPR or close_on_cpr is se= t > for all chardevs in the configuration. > Why not do the right thing by default? Could use some tests in tests/unit/test-char.c > Signed-off-by: Steve Sistare > --- > chardev/char.c | 41 ++++++++++++++++++++++++++++++++++++++--- > include/chardev/char.h | 5 +++++ > migration/cpr.c | 3 +++ > qapi/char.json | 5 ++++- > qemu-options.hx | 26 ++++++++++++++++++++++---- > 5 files changed, 72 insertions(+), 8 deletions(-) > > diff --git a/chardev/char.c b/chardev/char.c > index d959eec..f10fb94 100644 > --- a/chardev/char.c > +++ b/chardev/char.c > @@ -36,6 +36,7 @@ > #include "qemu/help_option.h" > #include "qemu/module.h" > #include "qemu/option.h" > +#include "qemu/env.h" > #include "qemu/id.h" > #include "qemu/coroutine.h" > #include "qemu/yank.h" > @@ -239,6 +240,9 @@ static void qemu_char_open(Chardev *chr, > ChardevBackend *backend, > ChardevClass *cc =3D CHARDEV_GET_CLASS(chr); > /* Any ChardevCommon member would work */ > ChardevCommon *common =3D backend ? backend->u.null.data : NULL; > + char fdname[40]; > Please use g_autoptr char *fdname =3D NULL; & g_strdup_printf() + > + chr->close_on_cpr =3D (common && common->close_on_cpr); > > if (common && common->has_logfile) { > int flags =3D O_WRONLY | O_CREAT; > @@ -248,7 +252,14 @@ static void qemu_char_open(Chardev *chr, > ChardevBackend *backend, > } else { > flags |=3D O_TRUNC; > } > - chr->logfd =3D qemu_open_old(common->logfile, flags, 0666); > + snprintf(fdname, sizeof(fdname), "%s_log", chr->label); > + chr->logfd =3D getenv_fd(fdname); > + if (chr->logfd < 0) { > + chr->logfd =3D qemu_open_old(common->logfile, flags, 0666); > + if (!chr->close_on_cpr) { > + setenv_fd(fdname, chr->logfd); > + } > + } > if (chr->logfd < 0) { > error_setg_errno(errp, errno, > "Unable to open logfile %s", > @@ -300,11 +311,12 @@ static void char_finalize(Object *obj) > if (chr->be) { > chr->be->chr =3D NULL; > } > - g_free(chr->filename); > - g_free(chr->label); > if (chr->logfd !=3D -1) { > close(chr->logfd); > + unsetenv_fdv("%s_log", chr->label); > } > + g_free(chr->filename); > + g_free(chr->label); > qemu_mutex_destroy(&chr->chr_write_lock); > } > > @@ -504,6 +516,8 @@ void qemu_chr_parse_common(QemuOpts *opts, > ChardevCommon *backend) > > backend->has_logappend =3D true; > backend->logappend =3D qemu_opt_get_bool(opts, "logappend", false); > + > + backend->close_on_cpr =3D qemu_opt_get_bool(opts, "close-on-cpr", > false); > If set to true and the backend doesn't implement the CPR feature, it should raise an error. } > > static const ChardevClass *char_get_class(const char *driver, Error > **errp) > @@ -945,6 +959,9 @@ QemuOptsList qemu_chardev_opts =3D { > },{ > .name =3D "abstract", > .type =3D QEMU_OPT_BOOL, > + },{ > + .name =3D "close-on-cpr", > + .type =3D QEMU_OPT_BOOL, > #endif > }, > { /* end of list */ } > @@ -1212,6 +1229,24 @@ GSource *qemu_chr_timeout_add_ms(Chardev *chr, > guint ms, > return source; > } > > +static int chr_cpr_capable(Object *obj, void *opaque) > +{ > + Chardev *chr =3D (Chardev *)obj; > + Error **errp =3D opaque; > + > + if (qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_CPR) || > chr->close_on_cpr) { > That'd be easy to misuse. Chardev should always explicitly support CPR feature (even if close_on_cpr is set) > + return 0; > + } > + error_setg(errp, "error: chardev %s -> %s is not capable of cpr", > + chr->label, chr->filename); > + return 1; > +} > + > +bool qemu_chr_cpr_capable(Error **errp) > +{ > + return !object_child_foreach(get_chardevs_root(), chr_cpr_capable, > errp); > +} > + > void qemu_chr_cleanup(void) > { > object_unparent(get_chardevs_root()); > diff --git a/include/chardev/char.h b/include/chardev/char.h > index 7c0444f..e488ad1 100644 > --- a/include/chardev/char.h > +++ b/include/chardev/char.h > @@ -50,6 +50,8 @@ typedef enum { > /* Whether the gcontext can be changed after calling > * qemu_chr_be_update_read_handlers() */ > QEMU_CHAR_FEATURE_GCONTEXT, > + /* Whether the device supports cpr */ > + QEMU_CHAR_FEATURE_CPR, > > QEMU_CHAR_FEATURE_LAST, > } ChardevFeature; > @@ -67,6 +69,7 @@ struct Chardev { > int be_open; > /* used to coordinate the chardev-change special-case: */ > bool handover_yank_instance; > + bool close_on_cpr; > GSource *gsource; > GMainContext *gcontext; > DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST); > @@ -291,4 +294,6 @@ void resume_mux_open(void); > /* console.c */ > void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error > **errp); > > +bool qemu_chr_cpr_capable(Error **errp); > + > #endif > diff --git a/migration/cpr.c b/migration/cpr.c > index 6333988..feff97f 100644 > --- a/migration/cpr.c > +++ b/migration/cpr.c > @@ -138,6 +138,9 @@ void cprexec(strList *args, Error **errp) > error_setg(errp, "cprexec requires cprsave with restart mode"); > return; > } > + if (!qemu_chr_cpr_capable(errp)) { > + return; > + } > if (vfio_cprsave(errp)) { > return; > } > diff --git a/qapi/char.json b/qapi/char.json > index adf2685..5efaf59 100644 > --- a/qapi/char.json > +++ b/qapi/char.json > @@ -204,12 +204,15 @@ > # @logfile: The name of a logfile to save output > # @logappend: true to append instead of truncate > # (default to false to truncate) > +# @close-on-cpr: if true, close device's fd on cprsave. defaults to fals= e. > +# since 6.1. > # > # Since: 2.6 > ## > { 'struct': 'ChardevCommon', > 'data': { '*logfile': 'str', > - '*logappend': 'bool' } } > + '*logappend': 'bool', > + '*close-on-cpr': 'bool' } } > > ## > # @ChardevFile: > diff --git a/qemu-options.hx b/qemu-options.hx > index fa53734..d5ff45f 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -3134,43 +3134,57 @@ DEFHEADING(Character device options:) > > DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, > "-chardev help\n" > - "-chardev null,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3D= on|off]\n" > + "-chardev > null,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off][,close-= on-cpr=3Don|off]\n" > "-chardev > socket,id=3Did[,host=3Dhost],port=3Dport[,to=3Dto][,ipv4=3Don|off][,ipv6= =3Don|off][,nodelay=3Don|off][,reconnect=3Dseconds]\n" > " > [,server=3Don|off][,wait=3Don|off][,telnet=3Don|off][,websocket=3Don|off= ][,reconnect=3Dseconds][,mux=3Don|off]\n" > - " > [,logfile=3DPATH][,logappend=3Don|off][,tls-creds=3DID][,tls-authz=3DID]= (tcp)\n" > + " > [,logfile=3DPATH][,logappend=3Don|off][,tls-creds=3DID][,tls-authz=3DID]= [,close-on-cpr=3Don|off] > (tcp)\n" > "-chardev > socket,id=3Did,path=3Dpath[,server=3Don|off][,wait=3Don|off][,telnet=3Don= |off][,websocket=3Don|off][,reconnect=3Dseconds]\n" > - " > [,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off][,abstract=3Don|off= ][,tight=3Don|off] > (unix)\n" > + " > [,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off][,abstract=3Don|off= ][,tight=3Don|off][,close-on-cpr=3Don|off] > (unix)\n" > "-chardev udp,id=3Did[,host=3Dhost],port=3Dport[,localaddr=3Dlocalad= dr]\n" > " > [,localport=3Dlocalport][,ipv4=3Don|off][,ipv6=3Don|off][,mux=3Don|off]\= n" > - " [,logfile=3DPATH][,logappend=3Don|off]\n" > + " [,logfile=3DPATH][,logappend=3Don|off][,close-on-cpr=3Don|= off]\n" > "-chardev > msmouse,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > vc,id=3Did[[,width=3Dwidth][,height=3Dheight]][[,cols=3Dcols][,rows=3Drow= s]]\n" > " [,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > ringbuf,id=3Did[,size=3Dsize][,logfile=3DPATH][,logappend=3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > file,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|= off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > pipe,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|= off]\n" > + " [,close-on-cpr=3Don|off]\n" > #ifdef _WIN32 > "-chardev > console,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off]\n" > "-chardev > serial,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3Do= n|off]\n" > #else > "-chardev pty,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3Do= n|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > stdio,id=3Did[,mux=3Don|off][,signal=3Don|off][,logfile=3DPATH][,logappen= d=3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > #endif > #ifdef CONFIG_BRLAPI > "-chardev > braille,id=3Did[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > #endif > #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ > || defined(__NetBSD__) || defined(__OpenBSD__) || > defined(__DragonFly__) > "-chardev > serial,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3Do= n|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > tty,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3Don|o= ff]\n" > + " [,close-on-cpr=3Don|off]\n" > #endif > #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) > "-chardev > parallel,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend= =3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > parport,id=3Did,path=3Dpath[,mux=3Don|off][,logfile=3DPATH][,logappend=3D= on|off]\n" > + " [,close-on-cpr=3Don|off]\n" > #endif > #if defined(CONFIG_SPICE) > "-chardev > spicevmc,id=3Did,name=3Dname[,debug=3Ddebug][,logfile=3DPATH][,logappend= =3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > "-chardev > spiceport,id=3Did,name=3Dname[,debug=3Ddebug][,logfile=3DPATH][,logappend= =3Don|off]\n" > + " [,close-on-cpr=3Don|off]\n" > #endif > , QEMU_ARCH_ALL > ) > @@ -3245,6 +3259,10 @@ The general form of a character device option is: > ``logappend`` option controls whether the log file will be truncated > or appended to when opened. > > + Every backend supports the ``close-on-cpr`` option. If on, the > + devices's descriptor is closed during cprsave, and reopened after > exec. > + This is useful for devices that do not support cpr. > + > The available backends are: > > ``-chardev null,id=3Did`` > -- > 1.8.3.1 > > > --=20 Marc-Andr=C3=A9 Lureau --000000000000d4926805c69ecba7 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi

On Wed, Jul 7, 2021 at 9:37 PM Stev= e Sistare <steven.sistare@o= racle.com> wrote:
Add QEMU_CHAR_FEATURE_CPR for devices that support cpr.
Add the chardev close_on_cpr option for devices that can be closed on cpr and reopened after exec.
cpr is allowed only if either QEMU_CHAR_FEATURE_CPR or close_on_cpr is set<= br> for all chardevs in the configuration.

= Why not do the right thing by default?

Could use s= ome tests in tests/unit/test-char.c


Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
=C2=A0chardev/char.c=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0| 41 ++++++++++++++++= ++++++++++++++++++++++---
=C2=A0include/chardev/char.h |=C2=A0 5 +++++
=C2=A0migration/cpr.c=C2=A0 =C2=A0 =C2=A0 =C2=A0 |=C2=A0 3 +++
=C2=A0qapi/char.json=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0|=C2=A0 5 ++++-
=C2=A0qemu-options.hx=C2=A0 =C2=A0 =C2=A0 =C2=A0 | 26 +++++++++++++++++++++= +----
=C2=A05 files changed, 72 insertions(+), 8 deletions(-)

diff --git a/chardev/char.c b/chardev/char.c
index d959eec..f10fb94 100644
--- a/chardev/char.c
+++ b/chardev/char.c
@@ -36,6 +36,7 @@
=C2=A0#include "qemu/help_option.h"
=C2=A0#include "qemu/module.h"
=C2=A0#include "qemu/option.h"
+#include "qemu/env.h"
=C2=A0#include "qemu/id.h"
=C2=A0#include "qemu/coroutine.h"
=C2=A0#include "qemu/yank.h"
@@ -239,6 +240,9 @@ static void qemu_char_open(Chardev *chr, ChardevBackend= *backend,
=C2=A0 =C2=A0 =C2=A0ChardevClass *cc =3D CHARDEV_GET_CLASS(chr);
=C2=A0 =C2=A0 =C2=A0/* Any ChardevCommon member would work */
=C2=A0 =C2=A0 =C2=A0ChardevCommon *common =3D backend ? backend->u.null.= data : NULL;
+=C2=A0 =C2=A0 char fdname[40];

Please = use g_autoptr char *fdname =3D NULL; & g_strdup_printf()
+
+=C2=A0 =C2=A0 chr->close_on_cpr =3D (common && common->close= _on_cpr);

=C2=A0 =C2=A0 =C2=A0if (common && common->has_logfile) {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0int flags =3D O_WRONLY | O_CREAT;
@@ -248,7 +252,14 @@ static void qemu_char_open(Chardev *chr, ChardevBacken= d *backend,
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0} else {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0flags |=3D O_TRUNC;
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0}
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 chr->logfd =3D qemu_open_old(common->log= file, flags, 0666);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 snprintf(fdname, sizeof(fdname), "%s_log&= quot;, chr->label);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 chr->logfd =3D getenv_fd(fdname);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 if (chr->logfd < 0) {
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 chr->logfd =3D qemu_open_old(= common->logfile, flags, 0666);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 if (!chr->close_on_cpr) {
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 setenv_fd(fdname, = chr->logfd);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 }
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 }
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0if (chr->logfd < 0) {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0error_setg_errno(errp, errn= o,
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 "Unable to open logfile %s",
@@ -300,11 +311,12 @@ static void char_finalize(Object *obj)
=C2=A0 =C2=A0 =C2=A0if (chr->be) {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0chr->be->chr =3D NULL;
=C2=A0 =C2=A0 =C2=A0}
-=C2=A0 =C2=A0 g_free(chr->filename);
-=C2=A0 =C2=A0 g_free(chr->label);
=C2=A0 =C2=A0 =C2=A0if (chr->logfd !=3D -1) {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0close(chr->logfd);
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 unsetenv_fdv("%s_log", chr->label= );
=C2=A0 =C2=A0 =C2=A0}
+=C2=A0 =C2=A0 g_free(chr->filename);
+=C2=A0 =C2=A0 g_free(chr->label);
=C2=A0 =C2=A0 =C2=A0qemu_mutex_destroy(&chr->chr_write_lock);
=C2=A0}

@@ -504,6 +516,8 @@ void qemu_chr_parse_common(QemuOpts *opts, ChardevCommo= n *backend)

=C2=A0 =C2=A0 =C2=A0backend->has_logappend =3D true;
=C2=A0 =C2=A0 =C2=A0backend->logappend =3D qemu_opt_get_bool(opts, "= ;logappend", false);
+
+=C2=A0 =C2=A0 backend->close_on_cpr =3D qemu_opt_get_bool(opts, "c= lose-on-cpr", false);

If set to tr= ue and the backend doesn't implement the CPR feature, it should raise a= n error.

=C2=A0}

=C2=A0static const ChardevClass *char_get_class(const char *driver, Error *= *errp)
@@ -945,6 +959,9 @@ QemuOptsList qemu_chardev_opts =3D {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0},{
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0.name =3D "abstract&qu= ot;,
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0.type =3D QEMU_OPT_BOOL, +=C2=A0 =C2=A0 =C2=A0 =C2=A0 },{
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 .name =3D "close-on-cpr&quo= t;,
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 .type =3D QEMU_OPT_BOOL,
=C2=A0#endif
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0},
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0{ /* end of list */ }
@@ -1212,6 +1229,24 @@ GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint= ms,
=C2=A0 =C2=A0 =C2=A0return source;
=C2=A0}

+static int chr_cpr_capable(Object *obj, void *opaque)
+{
+=C2=A0 =C2=A0 Chardev *chr =3D (Chardev *)obj;
+=C2=A0 =C2=A0 Error **errp =3D opaque;
+
+=C2=A0 =C2=A0 if (qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_CPR) || chr-= >close_on_cpr) {

That'd be easy = to misuse. Chardev should always explicitly support CPR feature (even if cl= ose_on_cpr is set)
=C2=A0
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 return 0;
+=C2=A0 =C2=A0 }
+=C2=A0 =C2=A0 error_setg(errp, "error: chardev %s -> %s is not cap= able of cpr",
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0chr->label, chr-= >filename);
+=C2=A0 =C2=A0 return 1;
+}
+
+bool qemu_chr_cpr_capable(Error **errp)
+{
+=C2=A0 =C2=A0 return !object_child_foreach(get_chardevs_root(), chr_cpr_ca= pable, errp);
+}
+
=C2=A0void qemu_chr_cleanup(void)
=C2=A0{
=C2=A0 =C2=A0 =C2=A0object_unparent(get_chardevs_root());
diff --git a/include/chardev/char.h b/include/chardev/char.h
index 7c0444f..e488ad1 100644
--- a/include/chardev/char.h
+++ b/include/chardev/char.h
@@ -50,6 +50,8 @@ typedef enum {
=C2=A0 =C2=A0 =C2=A0/* Whether the gcontext can be changed after calling =C2=A0 =C2=A0 =C2=A0 * qemu_chr_be_update_read_handlers() */
=C2=A0 =C2=A0 =C2=A0QEMU_CHAR_FEATURE_GCONTEXT,
+=C2=A0 =C2=A0 /* Whether the device supports cpr */
+=C2=A0 =C2=A0 QEMU_CHAR_FEATURE_CPR,

=C2=A0 =C2=A0 =C2=A0QEMU_CHAR_FEATURE_LAST,
=C2=A0} ChardevFeature;
@@ -67,6 +69,7 @@ struct Chardev {
=C2=A0 =C2=A0 =C2=A0int be_open;
=C2=A0 =C2=A0 =C2=A0/* used to coordinate the chardev-change special-case: = */
=C2=A0 =C2=A0 =C2=A0bool handover_yank_instance;
+=C2=A0 =C2=A0 bool close_on_cpr;
=C2=A0 =C2=A0 =C2=A0GSource *gsource;
=C2=A0 =C2=A0 =C2=A0GMainContext *gcontext;
=C2=A0 =C2=A0 =C2=A0DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
@@ -291,4 +294,6 @@ void resume_mux_open(void);
=C2=A0/* console.c */
=C2=A0void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error= **errp);

+bool qemu_chr_cpr_capable(Error **errp);
+
=C2=A0#endif
diff --git a/migration/cpr.c b/migration/cpr.c
index 6333988..feff97f 100644
--- a/migration/cpr.c
+++ b/migration/cpr.c
@@ -138,6 +138,9 @@ void cprexec(strList *args, Error **errp)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0error_setg(errp, "cprexec requires c= prsave with restart mode");
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0return;
=C2=A0 =C2=A0 =C2=A0}
+=C2=A0 =C2=A0 if (!qemu_chr_cpr_capable(errp)) {
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 return;
+=C2=A0 =C2=A0 }
=C2=A0 =C2=A0 =C2=A0if (vfio_cprsave(errp)) {
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0return;
=C2=A0 =C2=A0 =C2=A0}
diff --git a/qapi/char.json b/qapi/char.json
index adf2685..5efaf59 100644
--- a/qapi/char.json
+++ b/qapi/char.json
@@ -204,12 +204,15 @@
=C2=A0# @logfile: The name of a logfile to save output
=C2=A0# @logappend: true to append instead of truncate
=C2=A0#=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0(default to false to= truncate)
+# @close-on-cpr: if true, close device's fd on cprsave. defaults to fa= lse.
+#=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 since 6.1.
=C2=A0#
=C2=A0# Since: 2.6
=C2=A0##
=C2=A0{ 'struct': 'ChardevCommon',
=C2=A0 =C2=A0'data': { '*logfile': 'str',
-=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 '*logappend': 'bool&= #39; } }
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 '*logappend': 'bool&= #39;,
+=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 '*close-on-cpr': 'bo= ol' } }

=C2=A0##
=C2=A0# @ChardevFile:
diff --git a/qemu-options.hx b/qemu-options.hx
index fa53734..d5ff45f 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3134,43 +3134,57 @@ DEFHEADING(Character device options:)

=C2=A0DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
=C2=A0 =C2=A0 =C2=A0"-chardev help\n"
-=C2=A0 =C2=A0 "-chardev null,id=3Did[,mux=3Don|off][,logfile=3DPATH][= ,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "-chardev null,id=3Did[,mux=3Don|off][,logfile=3DPATH][= ,logappend=3Don|off][,close-on-cpr=3Don|off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev socket,id=3Did[,host=3Dhost],port=3Dport= [,to=3Dto][,ipv4=3Don|off][,ipv6=3Don|off][,nodelay=3Don|off][,reconnect=3D= seconds]\n"
=C2=A0 =C2=A0 =C2=A0"=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,server=3Don|o= ff][,wait=3Don|off][,telnet=3Don|off][,websocket=3Don|off][,reconnect=3Dsec= onds][,mux=3Don|off]\n"
-=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,logfile=3DPATH][,l= ogappend=3Don|off][,tls-creds=3DID][,tls-authz=3DID] (tcp)\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,logfile=3DPATH][,l= ogappend=3Don|off][,tls-creds=3DID][,tls-authz=3DID][,close-on-cpr=3Don|off= ] (tcp)\n"
=C2=A0 =C2=A0 =C2=A0"-chardev socket,id=3Did,path=3Dpath[,server=3Don|= off][,wait=3Don|off][,telnet=3Don|off][,websocket=3Don|off][,reconnect=3Dse= conds]\n"
-=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,mux=3Don|off][,log= file=3DPATH][,logappend=3Don|off][,abstract=3Don|off][,tight=3Don|off] (uni= x)\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,mux=3Don|off][,log= file=3DPATH][,logappend=3Don|off][,abstract=3Don|off][,tight=3Don|off][,clo= se-on-cpr=3Don|off] (unix)\n"
=C2=A0 =C2=A0 =C2=A0"-chardev udp,id=3Did[,host=3Dhost],port=3Dport[,l= ocaladdr=3Dlocaladdr]\n"
=C2=A0 =C2=A0 =C2=A0"=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,localport=3Dl= ocalport][,ipv4=3Don|off][,ipv6=3Don|off][,mux=3Don|off]\n"
-=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,logfile=3DPATH][,l= ogappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,logfile=3DPATH][,l= ogappend=3Don|off][,close-on-cpr=3Don|off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev msmouse,id=3Did[,mux=3Don|off][,logfile= =3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev vc,id=3Did[[,width=3Dwidth][,height=3Dhe= ight]][[,cols=3Dcols][,rows=3Drows]]\n"
=C2=A0 =C2=A0 =C2=A0"=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,mux=3Don|off]= [,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev ringbuf,id=3Did[,size=3Dsize][,logfile= =3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev file,id=3Did,path=3Dpath[,mux=3Don|off][= ,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev pipe,id=3Did,path=3Dpath[,mux=3Don|off][= ,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#ifdef _WIN32
=C2=A0 =C2=A0 =C2=A0"-chardev console,id=3Did[,mux=3Don|off][,logfile= =3DPATH][,logappend=3Don|off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev serial,id=3Did,path=3Dpath[,mux=3Don|off= ][,logfile=3DPATH][,logappend=3Don|off]\n"
=C2=A0#else
=C2=A0 =C2=A0 =C2=A0"-chardev pty,id=3Did[,mux=3Don|off][,logfile=3DPA= TH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev stdio,id=3Did[,mux=3Don|off][,signal=3Do= n|off][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#endif
=C2=A0#ifdef CONFIG_BRLAPI
=C2=A0 =C2=A0 =C2=A0"-chardev braille,id=3Did[,mux=3Don|off][,logfile= =3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#endif
=C2=A0#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \<= br> =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0|| defined(__NetBSD__) || defined(__OpenB= SD__) || defined(__DragonFly__)
=C2=A0 =C2=A0 =C2=A0"-chardev serial,id=3Did,path=3Dpath[,mux=3Don|off= ][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev tty,id=3Did,path=3Dpath[,mux=3Don|off][,= logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#endif
=C2=A0#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly= __)
=C2=A0 =C2=A0 =C2=A0"-chardev parallel,id=3Did,path=3Dpath[,mux=3Don|o= ff][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev parport,id=3Did,path=3Dpath[,mux=3Don|of= f][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#endif
=C2=A0#if defined(CONFIG_SPICE)
=C2=A0 =C2=A0 =C2=A0"-chardev spicevmc,id=3Did,name=3Dname[,debug=3Dde= bug][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0 =C2=A0 =C2=A0"-chardev spiceport,id=3Did,name=3Dname[,debug=3Dd= ebug][,logfile=3DPATH][,logappend=3Don|off]\n"
+=C2=A0 =C2=A0 "=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0[,close-on-cpr=3Don|= off]\n"
=C2=A0#endif
=C2=A0 =C2=A0 =C2=A0, QEMU_ARCH_ALL
=C2=A0)
@@ -3245,6 +3259,10 @@ The general form of a character device option is: =C2=A0 =C2=A0 =C2=A0``logappend`` option controls whether the log file will= be truncated
=C2=A0 =C2=A0 =C2=A0or appended to when opened.

+=C2=A0 =C2=A0 Every backend supports the ``close-on-cpr`` option.=C2=A0 If= on, the
+=C2=A0 =C2=A0 devices's descriptor is closed during cprsave, and reope= ned after exec.
+=C2=A0 =C2=A0 This is useful for devices that do not support cpr.
+
=C2=A0The available backends are:

=C2=A0``-chardev null,id=3Did``
--
1.8.3.1




--
Marc-Andr=C3=A9 Lureau
--000000000000d4926805c69ecba7--