1. 28 10月, 2015 5 次提交
  2. 23 10月, 2015 1 次提交
    • S
      powerpc/85xx: Load all early TLB entries at once · d9e1831a
      Scott Wood 提交于
      Use an AS=1 trampoline TLB entry to allow all normal TLB1 entries to
      be loaded at once.  This avoids the need to keep the translation that
      code is executing from in the same TLB entry in the final TLB
      configuration as during early boot, which in turn is helpful for
      relocatable kernels (e.g. kdump) where the kernel is not running from
      what would be the first TLB entry.
      
      On e6500, we limit map_mem_in_cams() to the primary hwthread of a
      core (the boot cpu is always considered primary, as a kdump kernel
      can be entered on any cpu).  Each TLB only needs to be set up once,
      and when we do, we don't want another thread to be running when we
      create a temporary trampoline TLB1 entry.
      Signed-off-by: NScott Wood <scottwood@freescale.com>
      d9e1831a
  3. 17 10月, 2015 13 次提交
  4. 15 10月, 2015 20 次提交
  5. 12 10月, 2015 1 次提交
    • A
      powerpc/mm: Differentiate between hugetlb and THP during page walk · 891121e6
      Aneesh Kumar K.V 提交于
      We need to properly identify whether a hugepage is an explicit or
      a transparent hugepage in follow_huge_addr(). We used to depend
      on hugepage shift argument to do that. But in some case that can
      result in wrong results. For ex:
      
      On finding a transparent hugepage we set hugepage shift to PMD_SHIFT.
      But we can end up clearing the thp pte, via pmdp_huge_get_and_clear.
      We do prevent reusing the pfn page via the usage of
      kick_all_cpus_sync(). But that happens after we updated the pte to 0.
      Hence in follow_huge_addr() we can find hugepage shift set, but transparent
      huge page check fail for a thp pte.
      
      NOTE: We fixed a variant of this race against thp split in commit
      691e95fd
      ("powerpc/mm/thp: Make page table walk safe against thp split/collapse")
      
      Without this patch, we may hit the BUG_ON(flags & FOLL_GET) in
      follow_page_mask occasionally.
      
      In the long term, we may want to switch ppc64 64k page size config to
      enable CONFIG_ARCH_WANT_GENERAL_HUGETLB
      Reported-by: NDavid Gibson <david@gibson.dropbear.id.au>
      Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      891121e6