1. 18 Oct, 2020 30 commits
  2. 27 Sep, 2020 9 commits
    • Linus Torvalds's avatar
      Linux 5.9-rc7 · a1b8638b
      Linus Torvalds authored
      a1b8638b
    • Linus Torvalds's avatar
      Merge tag 'kbuild-fixes-v5.9-4' of... · 16bc1d54
      Linus Torvalds authored
      Merge tag 'kbuild-fixes-v5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
      
      Pull Kbuild fixes from Masahiro Yamada:
      
       - ignore compiler stubs for PPC to fix builds
      
       - fix the usage of --target mentioned in the LLVM document
      
      * tag 'kbuild-fixes-v5.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
        Documentation/llvm: Fix clang target examples
        scripts/kallsyms: skip ppc compiler stub *.long_branch.* / *.plt_branch.*
      16bc1d54
    • Linus Torvalds's avatar
      Merge tag 'x86-urgent-2020-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · f8818559
      Linus Torvalds authored
      Pull x86 fixes from Thomas Gleixner:
       "Two fixes for the x86 interrupt code:
      
         - Unbreak the magic 'search the timer interrupt' logic in IO/APIC
           code which got wreckaged when the core interrupt code made the
           state tracking logic stricter.
      
           That caused the interrupt line to stay masked after switching from
           IO/APIC to PIC delivery mode, which obviously prevents interrupts
           from being delivered.
      
         - Make run_on_irqstack_code() typesafe. The function argument is a
           void pointer which is then cast to 'void (*fun)(void *).
      
           This breaks Control Flow Integrity checking in clang. Use proper
           helper functions for the three variants reuqired"
      
      * tag 'x86-urgent-2020-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/ioapic: Unbreak check_timer()
        x86/irq: Make run_on_irqstack_cond() typesafe
      f8818559
    • Linus Torvalds's avatar
      Merge tag 'timers-urgent-2020-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · ba25f057
      Linus Torvalds authored
      Pull timer updates from Thomas Gleixner:
       "A set of clocksource/clockevents updates:
      
         - Reset the TI/DM timer before enabling it instead of doing it the
           other way round.
      
         - Initialize the reload value for the GX6605s timer correctly so the
           hardware counter starts at 0 again after overrun.
      
         - Make error return value negative in the h8300 timer init function"
      
      * tag 'timers-urgent-2020-09-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        clocksource/drivers/timer-gx6605s: Fixup counter reload
        clocksource/drivers/timer-ti-dm: Do reset before enable
        clocksource/drivers/h8300_timer8: Fix wrong return value in h8300_8timer_init()
      ba25f057
    • Peter Xu's avatar
      mm/thp: Split huge pmds/puds if they're pinned when fork() · d042035e
      Peter Xu authored
      Pinned pages shouldn't be write-protected when fork() happens, because
      follow up copy-on-write on these pages could cause the pinned pages to
      be replaced by random newly allocated pages.
      
      For huge PMDs, we split the huge pmd if pinning is detected.  So that
      future handling will be done by the PTE level (with our latest changes,
      each of the small pages will be copied).  We can achieve this by let
      copy_huge_pmd() return -EAGAIN for pinned pages, so that we'll
      fallthrough in copy_pmd_range() and finally land the next
      copy_pte_range() call.
      
      Huge PUDs will be even more special - so far it does not support
      anonymous pages.  But it can actually be done the same as the huge PMDs
      even if the split huge PUDs means to erase the PUD entries.  It'll
      guarantee the follow up fault ins will remap the same pages in either
      parent/child later.
      
      This might not be the most efficient way, but it should be easy and
      clean enough.  It should be fine, since we're tackling with a very rare
      case just to make sure userspaces that pinned some thps will still work
      even without MADV_DONTFORK and after they fork()ed.
      Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d042035e
    • Peter Xu's avatar
      mm: Do early cow for pinned pages during fork() for ptes · 70e806e4
      Peter Xu authored
      This allows copy_pte_range() to do early cow if the pages were pinned on
      the source mm.
      
      Currently we don't have an accurate way to know whether a page is pinned
      or not.  The only thing we have is page_maybe_dma_pinned().  However
      that's good enough for now.  Especially, with the newly added
      mm->has_pinned flag to make sure we won't affect processes that never
      pinned any pages.
      
      It would be easier if we can do GFP_KERNEL allocation within
      copy_one_pte().  Unluckily, we can't because we're with the page table
      locks held for both the parent and child processes.  So the page
      allocation needs to be done outside copy_one_pte().
      
      Some trick is there in copy_present_pte(), majorly the wrprotect trick
      to block concurrent fast-gup.  Comments in the function should explain
      better in place.
      
      Oleg Nesterov reported a (probably harmless) bug during review that we
      didn't reset entry.val properly in copy_pte_range() so that potentially
      there's chance to call add_swap_count_continuation() multiple times on
      the same swp entry.  However that should be harmless since even if it
      happens, the same function (add_swap_count_continuation()) will return
      directly noticing that there're enough space for the swp counter.  So
      instead of a standalone stable patch, it is touched up in this patch
      directly.
      
      Link: https://lore.kernel.org/lkml/20200914143829.GA1424636@nvidia.com/Suggested-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      70e806e4
    • Peter Xu's avatar
      mm/fork: Pass new vma pointer into copy_page_range() · 7a4830c3
      Peter Xu authored
      This prepares for the future work to trigger early cow on pinned pages
      during fork().
      
      No functional change intended.
      Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7a4830c3
    • Peter Xu's avatar
      mm: Introduce mm_struct.has_pinned · 008cfe44
      Peter Xu authored
      (Commit message majorly collected from Jason Gunthorpe)
      
      Reduce the chance of false positive from page_maybe_dma_pinned() by
      keeping track if the mm_struct has ever been used with pin_user_pages().
      This allows cases that might drive up the page ref_count to avoid any
      penalty from handling dma_pinned pages.
      
      Future work is planned, to provide a more sophisticated solution, likely
      to turn it into a real counter.  For now, make it atomic_t but use it as
      a boolean for simplicity.
      Suggested-by: default avatarJason Gunthorpe <jgg@ziepe.ca>
      Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      008cfe44
    • Thomas Gleixner's avatar
      Merge tag 'timers-v5.9-rc4' of... · a7b6c0fe
      Thomas Gleixner authored
      Merge tag 'timers-v5.9-rc4' of https://git.linaro.org/people/daniel.lezcano/linux into timers/urgent
      
      Pull clocksource/clockevent fixes from Daniel Lezcano:
      
       - Fix wrong signed return value when checking of_iomap in the probe
         function for the h8300 timer (Tianjia Zhang)
      
       - Fix reset sequence when setting up the timer on the dm_timer (Tony
         Lindgren)
      
       - Fix counter reload when the interrupt fires on gx6605s (Guo Ren)
      a7b6c0fe
  3. 26 Sep, 2020 1 commit