On 03/21/2018 01:56 PM, Andrew Morton wrote:
On Wed, 21 Mar 2018 09:13:14 -0700 Mike Kravetz mike.kravetz@oracle.com wrote:
+static int shm_split(struct vm_area_struct *vma, unsigned long addr) +{
- struct file *file = vma->vm_file;
- struct shm_file_data *sfd = shm_file_data(file);
- if (sfd->vm_ops && sfd->vm_ops->split)
return sfd->vm_ops->split(vma, addr);This will be the only site which tests for NULL shm_file_data.vm_ops. It's a can't-happen, methinks.
You are correct, thanks for catching this.
I think I'll leave it as it is for now and will queue up a non-urgent patch:
From: Andrew Morton akpm@linux-foundation.org Subject: ipc/shm.c: shm_split(): remove unneeded test for NULL shm_file_data.vm_ops
This was added by the recent "ipc/shm.c: add split function to shm_vm_ops", but it is not necessary.
Cc: Laurent Dufour ldufour@linux.vnet.ibm.com Cc: Dan Williams dan.j.williams@intel.com Cc: Michal Hocko mhocko@suse.com Cc: Davidlohr Bueso dave@stgolabs.net Cc: Manfred Spraul manfred@colorfullife.com Signed-off-by: Andrew Morton akpm@linux-foundation.org
Looks good, FWIW Reviewed-by: Mike Kravetz mike.kravetz@oracle.com