[PATCH 0/5] VA allocator fixes

Nicholas Piggin npiggin at gmail.com
Mon Nov 6 21:03:10 AEDT 2017


Florian found a nasty corner case with the VA allocation logic
for crossing from 128TB to 512TB limit on hash, and made a
really superb report of the problem -- traces, reproducer recipes,
analysis, etc. which already mostly solved it.

The first patch in the series should solve Florian's particular
case, the next 3 are other issues with addr_limit. The last
patch is technically a cleanup but I think it's fairly important
in terms of understanding the code and also enabling some BUG
checks (when addr_limit == 0).

I have not tested these exactly on Florian's test case, but
some tests of my own behave better afterwards. Hopefully he has
time to re-test. Some careful review would be welcome too.

Thanks,
Nick

Nicholas Piggin (5):
  powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case
    allocation
  powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
  powerpc/64s/hash: Fix fork() with 512TB process address space
  powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case
    allocation
  powerpc/64s: mm_context.addr_limit is only used on hash

 arch/powerpc/include/asm/book3s/64/mmu-hash.h |  2 +-
 arch/powerpc/include/asm/book3s/64/mmu.h      |  2 +-
 arch/powerpc/include/asm/paca.h               |  2 +-
 arch/powerpc/kernel/asm-offsets.c             |  2 +-
 arch/powerpc/kernel/paca.c                    |  4 ++--
 arch/powerpc/kernel/setup-common.c            |  3 ++-
 arch/powerpc/mm/hugetlbpage-radix.c           | 14 +++++-------
 arch/powerpc/mm/mmap.c                        | 31 ++++++++++----------------
 arch/powerpc/mm/mmu_context_book3s64.c        |  8 +++----
 arch/powerpc/mm/slb_low.S                     |  2 +-
 arch/powerpc/mm/slice.c                       | 32 ++++++++++++++-------------
 11 files changed, 48 insertions(+), 54 deletions(-)

-- 
2.15.0



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