Re: [PATCH v2] shm: add split function to shm_vm_ops

2018-03-21 Thread Mike Kravetz
On 03/21/2018 01:56 PM, Andrew Morton wrote: > On Wed, 21 Mar 2018 09:13:14 -0700 Mike Kravetz > 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); >> + >> +

Re: [PATCH v2] shm: add split function to shm_vm_ops

2018-03-21 Thread Andrew Morton
On Wed, 21 Mar 2018 09:13:14 -0700 Mike Kravetz wrote: > If System V shmget/shmat operations are used to create a hugetlbfs > backed mapping, it is possible to munmap part of the mapping and > split the underlying vma such that it is not huge page aligned. > This will untimately result in the fol

Re: [PATCH v2] shm: add split function to shm_vm_ops

2018-03-21 Thread Dan Williams
On Wed, Mar 21, 2018 at 9:13 AM, Mike Kravetz wrote: > > If System V shmget/shmat operations are used to create a hugetlbfs > backed mapping, it is possible to munmap part of the mapping and > split the underlying vma such that it is not huge page aligned. > This will untimately result in the foll