Received-SPF: pass (google.com: domain of linux-crypto-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210127215010.99954-1-uwe@kleine-koenig.org>
In-Reply-To: <20210127215010.99954-1-uwe@kleine-koenig.org>
From:   Lijun Pan <lijunp213@gmail.com>
Date:   Fri, 29 Jan 2021 13:08:45 -0600
Message-ID: <CAOhMmr4ZMXS+R3AcdKm3qcePfuaZeC-0dNWvsSzowbv5hXo2-Q@mail.gmail.com>
Subject: Re: [PATCH] vio: make remove callback return void
To:     =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= <uwe@kleine-koenig.org>
Cc:     Michael Ellerman <mpe@ellerman.id.au>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jens Axboe <axboe@kernel.dk>, Matt Mackall <mpm@selenic.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Peter Huewe <peterhuewe@gmx.de>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Haren Myneni <haren@us.ibm.com>,
        =?UTF-8?Q?Breno_Leit=C3=A3o?= <leitao@debian.org>,
        Nayna Jain <nayna@linux.ibm.com>,
        Paulo Flabiano Smorigo <pfsmorigo@gmail.com>,
        Steven Royer <seroyer@linux.ibm.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Cristobal Forno <cforno12@linux.ibm.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Dany Madden <drt@linux.ibm.com>, Lijun Pan <ljp@linux.ibm.com>,
        Sukadev Bhattiprolu <sukadev@linux.ibm.com>,
        Tyrel Datwyler <tyreld@linux.ibm.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Michael Cyr <mikecyr@linux.ibm.com>,
        Jiri Slaby <jirislaby@kernel.org>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        sparclinux@vger.kernel.org, linux-block@vger.kernel.org,
        linux-crypto@vger.kernel.org, linux-integrity@vger.kernel.org,
        netdev@vger.kernel.org, linux-scsi@vger.kernel.org,
        target-devel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

On Wed, Jan 27, 2021 at 6:41 PM Uwe Kleine-K=C3=B6nig <uwe@kleine-koenig.or=
g> wrote:
>
> The driver core ignores the return value of struct bus_type::remove()
> because there is only little that can be done. To simplify the quest to
> make this function return void, let struct vio_driver::remove() return
> void, too. All users already unconditionally return 0, this commit makes
> it obvious that returning an error code is a bad idea and makes it
> obvious for future driver authors that returning an error code isn't
> intended.
>
> Note there are two nominally different implementations for a vio bus:
> one in arch/sparc/kernel/vio.c and the other in
> arch/powerpc/platforms/pseries/vio.c. I didn't care to check which
> driver is using which of these busses (or if even some of them can be
> used with both) and simply adapt all drivers and the two bus codes in
> one go.
>
> Note that for the powerpc implementation there is a semantical change:
> Before this patch for a device that was bound to a driver without a
> remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device
> core still considers the device unbound after vio_bus_remove() returns
> calling this unconditionally is the consistent behaviour which is
> implemented here.
>
> Signed-off-by: Uwe Kleine-K=C3=B6nig <uwe@kleine-koenig.org>

Acked-by: Lijun Pan <ljp@linux.ibm.com>