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    SubjectRe: [PATCH] barrier patch set
    Bartlomiej Zolnierkiewicz wrote:
    > On Saturday 20 of March 2004 00:01, Matthias Andree wrote:
    > >
    > > BTW, speaking of identify-device, hdparm -i (which uses
    > > HDIO_GET_IDENTITY) always returns "WriteCache=enabled" while hdparm -I
    > > that uses HDIO_DRIVE_CMD with WIN_PIDENTIFY reports the "correct" state
    > > that I've previously set with -W0. This is an i386 machine w/ 2.6.5-rc1.
    > >
    > > Is HDIO_GET_IDENTITY working correctly?
    > There were reports that on some drives you can't disable write cache
    > and even (?) that some drives lie (WC still enabled but marked as disabled).

    hdparm -i and -I ultimately both interpret WIN_IDENTIFY result, and both test
    bit 0x0020 of word 85. So it's unclear to me why they report a
    different write cache setting. I added a hexdump to dump_identity()
    in hdparm.c, and found that bit 0x0020 of word 85 is always set.

    BTW, 'cat /proc/ide/hda/identify' or 'hdparm -Istdin </dev/ide/hda/identify'
    reports the same value as hdparm -I, and that is consistent with
    the value I set with hdparm -W x.

    So, is HDIO_GET_IDENTITY broken?

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