The patch titled Subject: arm64/mm: use helper fault_signal_pending() has been added to the -mm tree. Its filename is arm64-mm-use-helper-fault_signal_pending.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/arm64-mm-use-helper-fault_signal_pending.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/arm64-mm-use-helper-fault_signal_pending.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Peter Xu <peterx@xxxxxxxxxx> Subject: arm64/mm: use helper fault_signal_pending() Let the arm64 fault handling to use the new fault_signal_pending() helper, by moving the signal handling out of the retry logic. Link: http://lkml.kernel.org/r/20200220155927.9264-1-peterx@xxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Bobby Powers <bobbypowers@xxxxxxxxx> Cc: Brian Geffon <bgeffon@xxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Denis Plotnikov <dplotnikov@xxxxxxxxxxxxx> Cc: "Dr . David Alan Gilbert" <dgilbert@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Jerome Glisse <jglisse@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: "Kirill A . Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Martin Cracauer <cracauer@xxxxxxxx> Cc: Marty McFadden <mcfadden8@xxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Maya Gokhale <gokhale2@xxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/mm/fault.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) --- a/arch/arm64/mm/fault.c~arm64-mm-use-helper-fault_signal_pending +++ a/arch/arm64/mm/fault.c @@ -513,19 +513,14 @@ retry: fault = __do_page_fault(mm, addr, mm_flags, vm_flags); major |= fault & VM_FAULT_MAJOR; - if (fault & VM_FAULT_RETRY) { - /* - * If we need to retry but a fatal signal is pending, - * handle the signal first. We do not need to release - * the mmap_sem because it would already be released - * in __lock_page_or_retry in mm/filemap.c. - */ - if (fatal_signal_pending(current)) { - if (!user_mode(regs)) - goto no_context; - return 0; - } + /* Quick path to respond to signals */ + if (fault_signal_pending(fault, regs)) { + if (!user_mode(regs)) + goto no_context; + return 0; + } + if (fault & VM_FAULT_RETRY) { /* * Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk of * starvation. _ Patches currently in -mm which might be from peterx@xxxxxxxxxx are mm-gup-rename-nonblocking-to-locked-where-proper.patch mm-gup-fix-__get_user_pages-on-fault-retry-of-hugetlb.patch mm-introduce-fault_signal_pending.patch x86-mm-use-helper-fault_signal_pending.patch arc-mm-use-helper-fault_signal_pending.patch arm64-mm-use-helper-fault_signal_pending.patch powerpc-mm-use-helper-fault_signal_pending.patch sh-mm-use-helper-fault_signal_pending.patch mm-return-faster-for-non-fatal-signals-in-user-mode-faults.patch userfaultfd-dont-retake-mmap_sem-to-emulate-nopage.patch mm-introduce-fault_flag_default.patch mm-introduce-fault_flag_interruptible.patch mm-allow-vm_fault_retry-for-multiple-times.patch mm-gup-allow-vm_fault_retry-for-multiple-times.patch mm-gup-allow-to-react-to-fatal-signals.patch mm-userfaultfd-honor-fault_flag_killable-in-fault-path.patch mm-merge-parameters-for-change_protection.patch userfaultfd-wp-apply-_page_uffd_wp-bit.patch userfaultfd-wp-drop-_page_uffd_wp-properly-when-fork.patch userfaultfd-wp-add-pmd_swp_uffd_wp-helpers.patch userfaultfd-wp-support-swap-and-page-migration.patch khugepaged-skip-collapse-if-uffd-wp-detected.patch userfaultfd-wp-dont-wake-up-when-doing-write-protect.patch userfaultfd-wp-declare-_uffdio_writeprotect-conditionally.patch userfaultfd-selftests-refactor-statistics.patch userfaultfd-selftests-add-write-protect-test.patch