[dpdk-dev] [PATCH 2/2] but/pci: fix fd close for hot-unplug

[Stephen Hemminger]

On Thu, 8 Nov 2018 11:10:29 +0800
Jeff Guo <jia.guo at intel.com> wrote:

> hi, stephen
> 
> On 11/8/2018 3:33 AM, Stephen Hemminger wrote:
> > On Wed,  7 Nov 2018 17:41:31 +0800
> > Jeff Guo <jia.guo at intel.com> wrote:
> >  
> >> When device is hot-unplugged, the device fd will be deleted in kernel.
> >> Then in the progress of detaching device, if it try to close the fd,
> >> it will cause a kernel crash, which shown a kernel null pointer error.  
> > If this happens, then it is a kernel bug and the kernel should be fixed.
> > Working around it in userspace is not a great long term solution.  
> 
> 
> agree with you. The key is sometime hold by kernel. But i think it is at 
> least reasonable for avoiding no-use process in user space, whatever 
> kernel's behavior. I am not sure if there is any better idea we can 
> find, but seems it is an option now.

Are you using igb_uio?  If so the problem is an DPDK supplied driver.
Let's fix that.  What is the backtrace on kernel crash.