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    SubjectRe: [PATCH] Re: cciss: warning: right shift count >= width of type
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    On Sun, 2007-08-12 at 07:58 +0100, Al Viro wrote:
    > On Sun, Aug 12, 2007 at 03:21:57AM +0200, Rene Herman wrote:
    > > @@ -2609,13 +2609,13 @@ static void do_cciss_request(request_queue_t *q)
    > > } else {
    > > c->Request.CDBLen = 16;
    > > c->Request.CDB[1]= 0;
    > > - c->Request.CDB[2]= (start_blk >> 56) & 0xff; //MSB
    > > - c->Request.CDB[3]= (start_blk >> 48) & 0xff;
    > > - c->Request.CDB[4]= (start_blk >> 40) & 0xff;
    > > - c->Request.CDB[5]= (start_blk >> 32) & 0xff;
    > > - c->Request.CDB[6]= (start_blk >> 24) & 0xff;
    > > - c->Request.CDB[7]= (start_blk >> 16) & 0xff;
    > > - c->Request.CDB[8]= (start_blk >> 8) & 0xff;
    > > + c->Request.CDB[2]= ((u64)start_blk >> 56) & 0xff; //MSB
    > > + c->Request.CDB[3]= ((u64)start_blk >> 48) & 0xff;
    > > + c->Request.CDB[4]= ((u64)start_blk >> 40) & 0xff;
    > > + c->Request.CDB[5]= ((u64)start_blk >> 32) & 0xff;
    > > + c->Request.CDB[6]= ((u64)start_blk >> 24) & 0xff;
    > > + c->Request.CDB[7]= ((u64)start_blk >> 16) & 0xff;
    > > + c->Request.CDB[8]= ((u64)start_blk >> 8) & 0xff;
    >
    > put_unaligned(cpu_to_be64(start_blk), &c->Request.CDB[2]);
    >
    > which is what's happening here anyway.

    Well ... this was debated a while ago ad nauseam:

    http://marc.info/?t=117699555300010

    The main objection to what you propose is that it forces the u64
    coercion even in the 32 bit start_blk case. The preferred solution as a
    result of that debate was simply to us a macro Andrew introduced:

    upper_32_bits()

    Which will silently replace zero in the non LBD case. I actually
    thought this had already been done.

    James


    James


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