dri-devel.lists.freedesktop.org archive mirror
 help / color / mirror / Atom feed
From: Cornelia Huck <cohuck@redhat.com>
To: Christoph Hellwig <hch@lst.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jason Gunthorpe <jgg@nvidia.com>,
	Alex Williamson <alex.williamson@redhat.com>,
	Kirti Wankhede <kwankhede@nvidia.com>
Cc: Tony Krowiak <akrowiak@linux.ibm.com>,
	Jason Herne <jjherne@linux.ibm.com>,
	kvm@vger.kernel.org, Vasily Gorbik <gor@linux.ibm.com>,
	Jonathan Corbet <corbet@lwn.net>, David Airlie <airlied@linux.ie>,
	linux-s390@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
	linux-doc@vger.kernel.org, dri-devel@lists.freedesktop.org,
	Halil Pasic <pasic@linux.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Rodrigo Vivi <rodrigo.vivi@intel.com>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH 01/10] driver core: Pull required checks into driver_probe_device()
Date: Tue, 15 Jun 2021 12:27:53 +0200	[thread overview]
Message-ID: <87h7hzxw0m.fsf@redhat.com> (raw)
In-Reply-To: <20210614150846.4111871-2-hch@lst.de>

On Mon, Jun 14 2021, Christoph Hellwig <hch@lst.de> wrote:

> From: Jason Gunthorpe <jgg@nvidia.com>
>
> Checking if the dev is dead or if the dev is already bound is a required
> precondition to invoking driver_probe_device(). All the call chains
> leading here duplicate these checks.
>
> Add it directly to driver_probe_device() so the precondition is clear and
> remove the checks from device_driver_attach() and
> __driver_attach_async_helper().
>
> The other call chain going through __device_attach_driver() does have
> these same checks but they are inlined into logic higher up the call stack
> and can't be removed.
>
> The sysfs uAPI call chain starting at bind_store() is a bit confused
> because it reads dev->driver unlocked and returns -ENODEV if it is !NULL,
> otherwise it reads it again under lock and returns 0 if it is !NULL. Fix
> this to always return -EBUSY and always read dev->driver under its lock.
>
> Done in preparation for the next patches which will add additional
> callers to driver_probe_device() and will need these checks as well.
>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> [hch: drop the extra checks in device_driver_attach and bind_store]
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/base/bus.c |  2 +-
>  drivers/base/dd.c  | 32 ++++++++++----------------------
>  2 files changed, 11 insertions(+), 23 deletions(-)

Reviewed-by: Cornelia Huck <cohuck@redhat.com>


  parent reply	other threads:[~2021-06-15 10:29 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20210614150846.4111871-1-hch@lst.de>
     [not found] ` <20210614150846.4111871-5-hch@lst.de>
2021-06-14 22:43   ` [PATCH 04/10] driver core: Don't return EPROBE_DEFER to userspace during sysfs bind Jason Gunthorpe
     [not found] ` <20210614150846.4111871-2-hch@lst.de>
2021-06-15  5:16   ` [PATCH 01/10] driver core: Pull required checks into driver_probe_device() Greg Kroah-Hartman
2021-06-15 10:27   ` Cornelia Huck [this message]
     [not found] ` <20210614150846.4111871-3-hch@lst.de>
2021-06-14 18:47   ` [PATCH 02/10] driver core: Better distinguish probe errors in really_probe Kirti Wankhede
2021-06-15  5:17   ` Greg Kroah-Hartman
2021-06-15  5:21 ` Allow mdev drivers to directly create the vfio_device (v2 / alternative) Greg Kroah-Hartman
     [not found]   ` <20210615055021.GB21080@lst.de>
2021-06-15 15:27     ` Jason Gunthorpe
     [not found] ` <20210614150846.4111871-4-hch@lst.de>
2021-06-15  5:18   ` [PATCH 03/10] driver core: Flow the return code from ->probe() through to sysfs bind Greg Kroah-Hartman
2021-06-15 10:31   ` Cornelia Huck
     [not found] ` <20210614150846.4111871-6-hch@lst.de>
2021-06-15  5:20   ` [PATCH 05/10] driver core: Export device_driver_attach() Greg Kroah-Hartman
2021-06-15 10:49   ` Cornelia Huck
     [not found] ` <20210614150846.4111871-7-hch@lst.de>
2021-06-15 10:50   ` [PATCH 06/10] vfio/mdev: Remove CONFIG_VFIO_MDEV_DEVICE Cornelia Huck
     [not found] ` <20210614150846.4111871-8-hch@lst.de>
2021-06-15 10:54   ` [PATCH 07/10] vfio/mdev: Allow the mdev_parent_ops to specify the device driver to bind Cornelia Huck

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87h7hzxw0m.fsf@redhat.com \
    --to=cohuck@redhat.com \
    --cc=airlied@linux.ie \
    --cc=akrowiak@linux.ibm.com \
    --cc=alex.williamson@redhat.com \
    --cc=borntraeger@de.ibm.com \
    --cc=corbet@lwn.net \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=gor@linux.ibm.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hca@linux.ibm.com \
    --cc=hch@lst.de \
    --cc=intel-gfx@lists.freedesktop.org \
    --cc=jgg@nvidia.com \
    --cc=jjherne@linux.ibm.com \
    --cc=kvm@vger.kernel.org \
    --cc=kwankhede@nvidia.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=pasic@linux.ibm.com \
    --cc=rafael@kernel.org \
    --cc=rodrigo.vivi@intel.com \
    --subject='Re: [PATCH 01/10] driver core: Pull required checks into driver_probe_device()' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).