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Date: Mon, 11 Feb 2019 15:12:35 +0800
From: Peter Xu <peterx@redhat.com>
Message-ID: <20190211071235.GE1011@xz-x1>
References: <20190206174328.9736-1-marcandre.lureau@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 3/6] terminal3270: do not use backend
 timer sources
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To: Cornelia Huck <cohuck@redhat.com>
Cc: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@redhat.com>, qemu-devel@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, Halil Pasic <pasic@linux.ibm.com>, Christian Borntraeger <borntraeger@de.ibm.com>, "open list:S390" <qemu-s390x@nongnu.org>

On Thu, Feb 07, 2019 at 06:14:15PM +0100, Cornelia Huck wrote:
> On Wed,  6 Feb 2019 18:43:25 +0100
> Marc-Andr=C3=A9 Lureau <marcandre.lureau@redhat.com> wrote:
>=20
> > terminal3270 uses the front-end side of the chardev. It shouldn't
> > create sources from backend side context (with backend
> > functions).
> >=20
> > send_timing_mark_cb calls qemu_chr_fe_write_all() which should be
> > thread safe.
> >=20
> > This partially reverts changes from commit
> > 2c716ba1506769c9be2caa02f0f6d6e7c00f4304.
> >=20
> > CC: Peter Xu <peterx@redhat.com>
> > Signed-off-by: Marc-Andr=C3=A9 Lureau <marcandre.lureau@redhat.com>
> > ---
> >  hw/char/terminal3270.c | 15 ++++++---------
> >  1 file changed, 6 insertions(+), 9 deletions(-)
>=20
> I've verified that 3270 continues to work as before.
>=20
> Acked-by: Cornelia Huck <cohuck@redhat.com>

A pure question: is it broken before this patch?

Asked since I don't understand this patch and what it tries to fix...
E.g., in terminal_init(), qemu_chr_fe_set_handlers() is always passing
NULL as chardev context so AFAICT this patch changes nothing from
functional-wise for now.  Meanwhile, if we pass in some non-NULL into
it in the future, IMHO this patch would break it instead of fixing
anything... anything I've missed?

Thanks,

--=20
Peter Xu