Re: arm64 crash in ffs on 4.9/4.12 - Internal error: Accessing user space memory with fs=KERNEL_DS

2017-08-30 Thread Greg KH
On Wed, Aug 30, 2017 at 01:27:32PM -0700, Jerry Zhang wrote: > Hi, > > I'm running into a kernel crash while using the functionfs driver on > 4.9 and 4.12 kernels. This is reproducible by using any of the aio > syscalls with functionfs on the above kernels. The code in question is > in

arm64 crash in ffs on 4.9/4.12 - Internal error: Accessing user space memory with fs=KERNEL_DS

2017-08-30 Thread Jerry Zhang
Hi, I'm running into a kernel crash while using the functionfs driver on 4.9 and 4.12 kernels. This is reproducible by using any of the aio syscalls with functionfs on the above kernels. The code in question is in ffs_user_copy_worker, which is a work thread that copies a bit of data into