Re: [PATCH 2/4] hw/ide/core: Clear LBA and drive bits for EXECUTE DEVICE DIAGNOSTIC

[Laurent Vivier]

CC:

John Snow <jsnow@redhat.com> (supporter:IDE)
qemu-block@nongnu.org (open list:IDE)

Le 28/05/2022 à 23:02, Lev Kujawski a écrit :
> Prior to this patch, cmd_exec_dev_diagnostic relied upon
> ide_set_signature to clear the device register.  While the
> preservation of the drive bit by ide_set_signature is necessary for
> the DEVICE RESET, IDENTIFY DEVICE, and READ SECTOR commands,
> ATA/ATAPI-6 specifies that "DEV shall be cleared to zero" for EXECUTE
> DEVICE DIAGNOSTIC.
>
> This deviation was uncovered by the ATACT Device Testing Program
> written by Hale Landis.
>
> Signed-off-by: Lev Kujawski <lkujaw@member.fsf.org>
> ---
>   hw/ide/core.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/hw/ide/core.c b/hw/ide/core.c
> index c2caa54285..5a24547e49 100644
> --- a/hw/ide/core.c
> +++ b/hw/ide/core.c
> @@ -1704,8 +1704,14 @@ static bool cmd_identify_packet(IDEState *s, uint8_t cmd)
>       return false;
>   }
>   
> +/* EXECUTE DEVICE DIAGNOSTIC */
>   static bool cmd_exec_dev_diagnostic(IDEState *s, uint8_t cmd)
>   {
> +    /*
> +     * Clear the device register per the ATA (v6) specification,
> +     * because ide_set_signature does not clear LBA or drive bits.
> +     */
> +    s->select = (ATA_DEV_ALWAYS_ON);
>       ide_set_signature(s);
>   
>       if (s->drive_kind == IDE_CD) {