From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dennis Dalessandro Subject: Re: [PATCH 09/10] IB/hfi1: Do not free hfi1 cdev parent structure early Date: Fri, 20 May 2016 11:57:02 -0400 Message-ID: <20160520155701.GA25234@phlsvsds.ph.intel.com> References: <20160519122318.22041.58871.stgit@scvm10.sc.intel.com> <20160519122642.22041.66203.stgit@scvm10.sc.intel.com> <20160519183100.GC26130@obsidianresearch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <20160519183100.GC26130-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jason Gunthorpe Cc: dledford-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Mitko Haralanov , Ira Weiny List-Id: linux-rdma@vger.kernel.org On Thu, May 19, 2016 at 12:31:00PM -0600, Jason Gunthorpe wrote: >On Thu, May 19, 2016 at 05:26:44AM -0700, Dennis Dalessandro wrote: >> static int hfi1_file_open(struct inode *inode, struct file *fp) >> { >> + struct hfi1_devdata *dd = container_of(inode->i_cdev, >> + struct hfi1_devdata, >> + user_cdev); >> + >> + /* Just take a ref now. Not all opens result in a context assign */ >> + kobject_get(&dd->kobj); > >Eh? > >If dd->kobj is passed as the parent to hfi1_cdev_init then cdev core >will do this for you, just confusing to duplicate it here?? I see your point. Will go ahead and remove it in the next version. >> @@ -1007,6 +1009,15 @@ void hfi1_free_devdata(struct hfi1_devdata *dd) >> rvt_dealloc_device(&dd->verbs_dev.rdi); > >Hurm. How are you synchronizing pci device removal with ioctls on the >cdev? This patch addresses the parent structure disappearing out from under the cdev. We are looking into if further work is needed around the pci device disappearing. I don't think there is anything specific to the ioctl changes though. In other words this is basically a port of write() to ioctl() so the same issues would be in both. Let me get back to you on this. -Denny -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html