1. 04 Jun, 2014 1 commit
  2. 16 May, 2014 1 commit
    • Mark Salter's avatar
      arm64: fix pud_huge() for 2-level pagetables · 4797ec2d
      Mark Salter authored
      The following happens when trying to run a kvm guest on a kernel
      configured for 64k pages. This doesn't happen with 4k pages:
        BUG: failure at include/linux/mm.h:297/put_page_testzero()!
        Kernel panic - not syncing: BUG!
        CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF            3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
        Call trace:
        [<fffffe0000096034>] dump_backtrace+0x0/0x16c
        [<fffffe00000961b4>] show_stack+0x14/0x1c
        [<fffffe000066e648>] dump_stack+0x84/0xb0
        [<fffffe0000668678>] panic+0xf4/0x220
        [<fffffe000018ec78>] free_reserved_area+0x0/0x110
        [<fffffe000018edd8>] free_pages+0x50/0x88
        [<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
        [<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
        [<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
        [<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
        [<fffffe00001edc1c>] __fput+0xb0/0x288
        [<fffffe00001ede4c>] ____fput+0xc/0x14
        [<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
        [<fffffe0000095c14>] do_notify_resume+0x54/0x58
      In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
      on the stage2 pgd which leads to the BUG in put_page_testzero(). This
      happens because a pud_huge() test in unmap_range() returns true when it
      should always be false with 2-level pages tables used by 64k pages.
      This patch removes support for huge puds if 2-level pagetables are
      being used.
      Signed-off-by: default avatarMark Salter <msalter@redhat.com>
      [catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
      Cc: <stable@vger.kernel.org> # v3.11+
  3. 11 Sep, 2013 1 commit
    • Naoya Horiguchi's avatar
      mm: migrate: check movability of hugepage in unmap_and_move_huge_page() · 83467efb
      Naoya Horiguchi authored
      Currently hugepage migration works well only for pmd-based hugepages
      (mainly due to lack of testing,) so we had better not enable migration of
      other levels of hugepages until we are ready for it.
      Some users of hugepage migration (mbind, move_pages, and migrate_pages) do
      page table walk and check pud/pmd_huge() there, so they are safe.  But the
      other users (softoffline and memory hotremove) don't do this, so without
      this patch they can try to migrate unexpected types of hugepages.
      To prevent this, we introduce hugepage_migration_support() as an
      architecture dependent check of whether hugepage are implemented on a pmd
      basis or not.  And on some architecture multiple sizes of hugepages are
      available, so hugepage_migration_support() also checks hugepage size.
      Signed-off-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Hillf Danton <dhillf@gmail.com>
      Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  4. 14 Jun, 2013 1 commit
    • Steve Capper's avatar
      ARM64: mm: HugeTLB support. · 084bd298
      Steve Capper authored
      Add huge page support to ARM64, different huge page sizes are
      supported depending on the size of normal pages:
      PAGE_SIZE is 4KB:
         2MB - (pmds) these can be allocated at any time.
      1024MB - (puds) usually allocated on bootup with the command line
               with something like: hugepagesz=1G hugepages=6
      PAGE_SIZE is 64KB:
       512MB - (pmds) usually allocated on bootup via command line.
      Signed-off-by: default avatarSteve Capper <steve.capper@linaro.org>
      Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>