From: Jason Gunthorpe <jgg@nvidia.com>
To: Dave Jiang <dave.jiang@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>,
Vinod Koul <vkoul@kernel.org>,
dmaengine@vger.kernel.org
Subject: Re: [PATCH v7 8/8] dmaengine: idxd: fix cdev setup and free device lifetime issues
Date: Mon, 22 Mar 2021 21:02:57 -0300 [thread overview]
Message-ID: <20210323000257.GY2356281@nvidia.com> (raw)
In-Reply-To: <60f12cfc-6f5a-7f0f-e88a-ab0e15b6d759@intel.com>
On Mon, Mar 22, 2021 at 04:44:24PM -0700, Dave Jiang wrote:
>
> On 3/22/2021 4:38 PM, Dan Williams wrote:
> > On Mon, Mar 22, 2021 at 4:32 PM Dave Jiang <dave.jiang@intel.com> wrote:
> > > The char device setup and cleanup has device lifetime issues regarding when
> > > parts are initialized and cleaned up. The initialization of struct device is
> > > done incorrectly. device_initialize() needs to be called on the 'struct
> > > device' and then additional changes can be added. The ->release() function
> > > needs to be setup via device_type before dev_set_name() to allow proper
> > > cleanup. The change re-parents the cdev under the wq->conf_dev to get
> > > natural reference inheritance. No known dependency on the old device path exists.
> > >
> > > Reported-by: Jason Gunthorpe <jgg@nvidia.com>
> > > Fixes: 42d279f9137a ("dmaengine: idxd: add char driver to expose submission portal to userland")
> > > Signed-off-by: Dave Jiang <dave.jiang@intel.com>
> > > Reviewed-by: Dan Williams <dan.j.williams@intel.com>
> > [..]
> > > diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
> > > index 03079ff54889..8a08988ea9d1 100644
> > > +++ b/drivers/dma/idxd/sysfs.c
> > > @@ -1174,8 +1174,14 @@ static ssize_t wq_cdev_minor_show(struct device *dev,
> > > struct device_attribute *attr, char *buf)
> > > {
> > > struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> > > + int minor = -1;
> > >
> > > - return sprintf(buf, "%d\n", wq->idxd_cdev.minor);
> > > + mutex_lock(&wq->wq_lock);
> > > + if (wq->idxd_cdev)
> > > + minor = wq->idxd_cdev->minor;
> > > + mutex_unlock(&wq->wq_lock);
> > > +
> > > + return sprintf(buf, "%d\n", minor);
> > As I mentioned, let's not emit a negative value here. ...not that
> > userspace should be using this awkward recreation of the existing core
> > 'dev' attribute anyway.
> >
> > if (minor == -1)
> > return -ENXIO;
> > return sprintf(buf, "%d\n", minor);
> Ok I'll update. This will go away when we convert to UACCE based driver.
Also ensure all new syfs callbacks are using sysfs_emit()
Jason
next prev parent reply other threads:[~2021-03-23 0:04 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-22 23:31 [PATCH v7 0/8] idxd 'struct device' lifetime handling fixes Dave Jiang
2021-03-22 23:31 ` [PATCH v7 1/8] dmaengine: idxd: fix dma device lifetime Dave Jiang
2021-03-22 23:31 ` [PATCH v7 2/8] dmaengine: idxd: cleanup pci interrupt vector allocation management Dave Jiang
2021-03-22 23:31 ` [PATCH v7 3/8] dmaengine: idxd: removal of pcim managed mmio mapping Dave Jiang
2021-03-22 23:31 ` [PATCH v7 4/8] dmaengine: idxd: fix idxd conf_dev 'struct device' lifetime Dave Jiang
2021-03-22 23:31 ` [PATCH v7 5/8] dmaengine: idxd: fix wq " Dave Jiang
2021-03-22 23:31 ` [PATCH v7 6/8] dmaengine: idxd: fix engine conf_dev lifetime Dave Jiang
2021-03-22 23:31 ` [PATCH v7 7/8] dmaengine: idxd: fix group " Dave Jiang
2021-03-22 23:32 ` [PATCH v7 8/8] dmaengine: idxd: fix cdev setup and free device lifetime issues Dave Jiang
2021-03-22 23:38 ` Dan Williams
2021-03-22 23:44 ` Dave Jiang
2021-03-23 0:02 ` Jason Gunthorpe [this message]
2021-03-23 14:48 ` Dave Jiang
2021-03-23 11:45 ` [PATCH v7 0/8] idxd 'struct device' lifetime handling fixes Vinod Koul
2021-03-23 11:56 ` Jason Gunthorpe
2021-03-23 15:44 ` Dave Jiang
2021-03-24 13:56 ` Jason Gunthorpe
2021-03-24 14:57 ` Dave Jiang
2021-03-24 15:03 ` Jason Gunthorpe
2021-03-25 6:28 ` Vinod Koul
2021-03-25 15:25 ` Dave Jiang
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