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    SubjectRe: [PATCH 1/3] scsi: hisi_sas: Use devm_bitmap_zalloc() when applicable
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    On 26/11/2021 21:15, Christophe JAILLET wrote:
    > 'hisi_hba->slot_index_tags' is a bitmap. So use 'devm_bitmap_zalloc()' to
    > simplify code, improve the semantic and avoid some open-coded arithmetic
    > in allocator arguments.
    >
    > Signed-off-by: Christophe JAILLET<christophe.jaillet@wanadoo.fr>

    Acked-by: John Garry <john.garry@huawei.com>

    > ---
    > The use of 's' is questionable here. I've left it because it looks more
    > consistent this way with the surrounding code.
    >
    > Can it be an issue to have the length of the allocated bitmap not being
    > a multiple of sizeof(long)?

    The driver does not rely on that (allocated bitmap being a multiple of
    sizeof(long)), but the size is 4096 bits, which would be a multiple of
    sizeof(long)

    Thanks,
    John

    > I guess that there is some kind of 'rounding' done by the memory allocator
    > to keep some alignment, so I think that the previous code is safe (but not
    > logical).
    > If this is not the case, there is a potential out of bound bug related to
    > the bitmap API that expect to access only longs (which is not necessarily
    > the case here).

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