v2:
- resent previous version, rebase only
This series is split out of userfaultfd-wp series to only cover the
general page fault changes, since it seems to make sense itself.
Basically it does two things:
(a) Allows the page fault handlers to be more interactive on not
only SIGKILL, but also the rest of userspace signals (especially
for user-mode faults), and,
(b) Allows the page fault retry (VM_FAULT_RETRY) to happen for more
than once.
I'm keeping the CC list as in uffd-wp v5, hopefully I'm not sending
too much spams...
And, instead of writting again the cover letter, I'm just copy-pasting
my previous link here which has more details on why we do this:
https://patchwork.kernel.org/cover/10691991/
The major change from that latest version should be that we introduced
a new page fault flag FAULT_FLAG_INTERRUPTIBLE as suggested by Linus
[1] to represents that we would like the fault handler to respond to
non-fatal signals. Also, we're more careful now on when to do the
immediate return of the page fault for such signals. For example, now
we'll only check against signal_pending() for user-mode page faults
and we keep the kernel-mode page fault patch untouched for it. More
information can be found in separate patches.
The patchset is only lightly tested on x86.
All comments are greatly welcomed. Thanks,
[1] https://lkml.org/lkml/2019/6/25/1382
Peter Xu (7):
mm/gup: Rename "nonblocking" to "locked" where proper
mm: Introduce FAULT_FLAG_DEFAULT
mm: Introduce FAULT_FLAG_INTERRUPTIBLE
mm: Return faster for non-fatal signals in user mode faults
userfaultfd: Don't retake mmap_sem to emulate NOPAGE
mm: Allow VM_FAULT_RETRY for multiple times
mm/gup: Allow VM_FAULT_RETRY for multiple times
arch/alpha/mm/fault.c | 7 +--
arch/arc/mm/fault.c | 8 +++-
arch/arm/mm/fault.c | 14 +++---
arch/arm64/mm/fault.c | 16 +++----
arch/hexagon/mm/vm_fault.c | 6 +--
arch/ia64/mm/fault.c | 6 +--
arch/m68k/mm/fault.c | 10 ++--
arch/microblaze/mm/fault.c | 6 +--
arch/mips/mm/fault.c | 6 +--
arch/nds32/mm/fault.c | 12 ++---
arch/nios2/mm/fault.c | 8 ++--
arch/openrisc/mm/fault.c | 6 +--
arch/parisc/mm/fault.c | 9 ++--
arch/powerpc/mm/fault.c | 10 ++--
arch/riscv/mm/fault.c | 12 ++---
arch/s390/mm/fault.c | 11 ++---
arch/sh/mm/fault.c | 7 ++-
arch/sparc/mm/fault_32.c | 5 +-
arch/sparc/mm/fault_64.c | 6 +--
arch/um/kernel/trap.c | 7 +--
arch/unicore32/mm/fault.c | 11 ++---
arch/x86/mm/fault.c | 6 +--
arch/xtensa/mm/fault.c | 6 +--
drivers/gpu/drm/ttm/ttm_bo_vm.c | 12 +++--
fs/userfaultfd.c | 28 +-----------
include/linux/mm.h | 81 +++++++++++++++++++++++++++++----
include/linux/sched/signal.h | 12 +++++
mm/filemap.c | 2 +-
mm/gup.c | 61 ++++++++++++++-----------
mm/hugetlb.c | 14 +++---
mm/shmem.c | 2 +-
31 files changed, 227 insertions(+), 180 deletions(-)
--
2.21.0
