Eric Lee / smarc-fsl-linux-kernel

06 Oct, 2018

1 commit

  • 518968645   mm/gup_benchmark: fix unsigned comparison to zero in __gup_benchmark_ioctl ... Browse Code »

    get_user_pages_fast() will return negative value if no pages were pinned,
    then be converted to a unsigned, which is compared to zero, giving the
    wrong result.

    Link: http://lkml.kernel.org/r/20180921095015.26088-1-yuehaibing@huawei.com
    Fixes: 09e35a4a1ca8 ("mm/gup_benchmark: handle gup failures")
    Signed-off-by: YueHaibing
    Reviewed-by: Andrew Morton
    Cc: Michael S. Tsirkin
    Signed-off-by: Andrew Morton
    Signed-off-by: Greg Kroah-Hartman

    YueHaibing
     

13 Jun, 2018

1 commit

  • 778e1cdd8   treewide: kvzalloc() -> kvcalloc() ... Browse Code »

    The kvzalloc() function has a 2-factor argument form, kvcalloc(). This
    patch replaces cases of:

    kvzalloc(a * b, gfp)

    with:
    kvcalloc(a * b, gfp)

    as well as handling cases of:

    kvzalloc(a * b * c, gfp)

    with:

    kvzalloc(array3_size(a, b, c), gfp)

    as it's slightly less ugly than:

    kvcalloc(array_size(a, b), c, gfp)

    This does, however, attempt to ignore constant size factors like:

    kvzalloc(4 * 1024, gfp)

    though any constants defined via macros get caught up in the conversion.

    Any factors with a sizeof() of "unsigned char", "char", and "u8" were
    dropped, since they're redundant.

    The Coccinelle script used for this was:

    // Fix redundant parens around sizeof().
    @@
    type TYPE;
    expression THING, E;
    @@

    (
    kvzalloc(
    - (sizeof(TYPE)) * E
    + sizeof(TYPE) * E
    , ...)
    |
    kvzalloc(
    - (sizeof(THING)) * E
    + sizeof(THING) * E
    , ...)
    )

    // Drop single-byte sizes and redundant parens.
    @@
    expression COUNT;
    typedef u8;
    typedef __u8;
    @@

    (
    kvzalloc(
    - sizeof(u8) * (COUNT)
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(__u8) * (COUNT)
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(char) * (COUNT)
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(unsigned char) * (COUNT)
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(u8) * COUNT
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(__u8) * COUNT
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(char) * COUNT
    + COUNT
    , ...)
    |
    kvzalloc(
    - sizeof(unsigned char) * COUNT
    + COUNT
    , ...)
    )

    // 2-factor product with sizeof(type/expression) and identifier or constant.
    @@
    type TYPE;
    expression THING;
    identifier COUNT_ID;
    constant COUNT_CONST;
    @@

    (
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * (COUNT_ID)
    + COUNT_ID, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * COUNT_ID
    + COUNT_ID, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * (COUNT_CONST)
    + COUNT_CONST, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * COUNT_CONST
    + COUNT_CONST, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * (COUNT_ID)
    + COUNT_ID, sizeof(THING)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * COUNT_ID
    + COUNT_ID, sizeof(THING)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * (COUNT_CONST)
    + COUNT_CONST, sizeof(THING)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * COUNT_CONST
    + COUNT_CONST, sizeof(THING)
    , ...)
    )

    // 2-factor product, only identifiers.
    @@
    identifier SIZE, COUNT;
    @@

    - kvzalloc
    + kvcalloc
    (
    - SIZE * COUNT
    + COUNT, SIZE
    , ...)

    // 3-factor product with 1 sizeof(type) or sizeof(expression), with
    // redundant parens removed.
    @@
    expression THING;
    identifier STRIDE, COUNT;
    type TYPE;
    @@

    (
    kvzalloc(
    - sizeof(TYPE) * (COUNT) * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE) * (COUNT) * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE) * COUNT * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE) * COUNT * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(TYPE))
    , ...)
    |
    kvzalloc(
    - sizeof(THING) * (COUNT) * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kvzalloc(
    - sizeof(THING) * (COUNT) * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kvzalloc(
    - sizeof(THING) * COUNT * (STRIDE)
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    |
    kvzalloc(
    - sizeof(THING) * COUNT * STRIDE
    + array3_size(COUNT, STRIDE, sizeof(THING))
    , ...)
    )

    // 3-factor product with 2 sizeof(variable), with redundant parens removed.
    @@
    expression THING1, THING2;
    identifier COUNT;
    type TYPE1, TYPE2;
    @@

    (
    kvzalloc(
    - sizeof(TYPE1) * sizeof(TYPE2) * COUNT
    + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
    , ...)
    |
    kvzalloc(
    - sizeof(THING1) * sizeof(THING2) * COUNT
    + array3_size(COUNT, sizeof(THING1), sizeof(THING2))
    , ...)
    |
    kvzalloc(
    - sizeof(THING1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(THING1), sizeof(THING2))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE1) * sizeof(THING2) * COUNT
    + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
    , ...)
    |
    kvzalloc(
    - sizeof(TYPE1) * sizeof(THING2) * (COUNT)
    + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
    , ...)
    )

    // 3-factor product, only identifiers, with redundant parens removed.
    @@
    identifier STRIDE, SIZE, COUNT;
    @@

    (
    kvzalloc(
    - (COUNT) * STRIDE * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - COUNT * (STRIDE) * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - COUNT * STRIDE * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - (COUNT) * (STRIDE) * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - COUNT * (STRIDE) * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - (COUNT) * STRIDE * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - (COUNT) * (STRIDE) * (SIZE)
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    |
    kvzalloc(
    - COUNT * STRIDE * SIZE
    + array3_size(COUNT, STRIDE, SIZE)
    , ...)
    )

    // Any remaining multi-factor products, first at least 3-factor products,
    // when they're not all constants...
    @@
    expression E1, E2, E3;
    constant C1, C2, C3;
    @@

    (
    kvzalloc(C1 * C2 * C3, ...)
    |
    kvzalloc(
    - (E1) * E2 * E3
    + array3_size(E1, E2, E3)
    , ...)
    |
    kvzalloc(
    - (E1) * (E2) * E3
    + array3_size(E1, E2, E3)
    , ...)
    |
    kvzalloc(
    - (E1) * (E2) * (E3)
    + array3_size(E1, E2, E3)
    , ...)
    |
    kvzalloc(
    - E1 * E2 * E3
    + array3_size(E1, E2, E3)
    , ...)
    )

    // And then all remaining 2 factors products when they're not all constants,
    // keeping sizeof() as the second factor argument.
    @@
    expression THING, E1, E2;
    type TYPE;
    constant C1, C2, C3;
    @@

    (
    kvzalloc(sizeof(THING) * C2, ...)
    |
    kvzalloc(sizeof(TYPE) * C2, ...)
    |
    kvzalloc(C1 * C2 * C3, ...)
    |
    kvzalloc(C1 * C2, ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * (E2)
    + E2, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(TYPE) * E2
    + E2, sizeof(TYPE)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * (E2)
    + E2, sizeof(THING)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - sizeof(THING) * E2
    + E2, sizeof(THING)
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - (E1) * E2
    + E1, E2
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - (E1) * (E2)
    + E1, E2
    , ...)
    |
    - kvzalloc
    + kvcalloc
    (
    - E1 * E2
    + E1, E2
    , ...)
    )

    Signed-off-by: Kees Cook

    Kees Cook
     

14 Apr, 2018

1 commit

  • 09e35a4a1   mm/gup_benchmark: handle gup failures ... Browse Code »

    Patch series "mm/get_user_pages_fast fixes, cleanups", v2.

    Turns out get_user_pages_fast and __get_user_pages_fast return different
    values on error when given a single page: __get_user_pages_fast returns
    0. get_user_pages_fast returns either 0 or an error.

    Callers of get_user_pages_fast expect an error so fix it up to return an
    error consistently.

    Stress the difference between get_user_pages_fast and
    __get_user_pages_fast to make sure callers aren't confused.

    This patch (of 3):

    __gup_benchmark_ioctl does not handle the case where get_user_pages_fast
    fails:

    - a negative return code will cause a buffer overrun

    - returning with partial success will cause use of uninitialized
    memory.

    [akpm@linux-foundation.org: simplification]
    Link: http://lkml.kernel.org/r/1522962072-182137-3-git-send-email-mst@redhat.com
    Signed-off-by: Michael S. Tsirkin
    Reviewed-by: Andrew Morton
    Cc: Kirill A. Shutemov
    Cc: Huang Ying
    Cc: Jonathan Corbet
    Cc: Peter Zijlstra
    Cc: Thomas Gleixner
    Cc: Thorsten Leemhuis
    Cc:
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Michael S. Tsirkin
     

18 Nov, 2017

1 commit

  • 64c349f4a   mm: add infrastructure for get_user_pages_fast() benchmarking ... Browse Code »

    Performance of get_user_pages_fast() is critical for some workloads, but
    it's tricky to test it directly.

    This patch provides /sys/kernel/debug/gup_benchmark that helps with
    testing performance of it.

    See tools/testing/selftests/vm/gup_benchmark.c for userspace
    counterpart.

    Link: http://lkml.kernel.org/r/20170908215603.9189-2-kirill.shutemov@linux.intel.com
    Signed-off-by: Kirill A. Shutemov
    Cc: Shuah Khan
    Cc: Ingo Molnar
    Cc: Thorsten Leemhuis
    Cc: Jonathan Corbet
    Cc: Huang Ying
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Kirill A. Shutemov