A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-28 10:41:38 -04:00
Code Issues Projects Releases Packages Wiki Activity

BACKPORT: FROMGIT: userfaultfd/shmem: support minor fault registration for shmem

Browse source 
This patch allows shmem-backed VMAs to be registered for minor faults.
Minor faults are appropriately relayed to userspace in the fault path, for
VMAs with the relevant flag.

This commit doesn't hook up the UFFDIO_CONTINUE ioctl for shmem-backed
minor faults, though, so userspace doesn't yet have a way to resolve such
faults.

Because of this, we also don't yet advertise this as a supported feature.
That will be done in a separate commit when the feature is fully
implemented.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Axel Rasmussen <[email protected]>
Acked-by: Peter Xu <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Cc: Alexander Viro <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Brian Geffon <[email protected]>
Cc: "Dr . David Alan Gilbert" <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Lokesh Gidra <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Mina Almasry <[email protected]>
Cc: Oliver Upton <[email protected]>
Cc: Shaohua Li <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Wang Qing <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
(cherry picked from commit 6867a29320b7d178feb9786856e5ea2cf40f6d33
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git akpm)
Link: https://lore.kernel.org/patchwork/patch/1420970/

Conflicts: mm/shmem.c
(Manual rebase)

Signed-off-by: Lokesh Gidra <[email protected]>
Bug: 187930641
Change-Id: Ib8e3fe202feab7404742814f4250a0981065368c
This commit is contained in:
Axel Rasmussen 2021-05-14 10:39:49 +10:00 • committed by Michael Bestas
commit ec166f77f9
3 changed files with 17 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

3
fs/userfaultfd.c
View file

@ -1305,8 +1305,7 @@ static inline bool vma_can_userfault(struct vm_area_struct *vma,
unsigned long vm_flags)
{
if (vm_flags & VM_UFFD_MINOR) {
/* FIXME: Add minor fault interception for shmem. */
if (!is_vm_hugetlb_page(vma))
if (!(is_vm_hugetlb_page(vma) || vma_is_shmem(vma)))
return false;
}