On 8/29/17 6:42 AM, Christoph Hellwig wrote:
> ---
> From e661047ec3a25587648b07c02a687a7dac778f3b Mon Sep 17 00:00:00 2001
> From: Christoph Hellwig <h...@lst.de>
> Date: Tue, 29 Aug 2017 14:35:50 +0200
> Subject: libata: check for trusted computing in IDENTIFY DEVICE data
> 
> ATA-8 and later mirrors the TRUSTED COMPUTING SUPPORTED bit in word 48 of
> the IDENTIFY DEVICE data.  Check this before issuing a READ LOG PAGE
> command to avoid issues with buggy devices.  The only downside is that
> we can't support Security Send / Receive for a device with an older
> revision due to the conflicting use of this field in earlier
> specifications.
> 
> Signed-off-by: Christoph Hellwig <h...@lst.de>
> ---
>  drivers/ata/libata-core.c |  3 +++
>  include/linux/ata.h       | 10 +++++++++-
>  2 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index 697f5f896b19..ca57b03ab950 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -2413,6 +2413,9 @@ static void ata_dev_config_trusted(struct ata_device 
> *dev)
>       u64 trusted_cap;
>       unsigned int err;
>  
> +     if (!ata_id_has_trusted(dev->id))
> +             return;
> +
>       if (!ata_identify_page_supported(dev, ATA_LOG_SECURITY)) {
>               ata_dev_warn(dev,
>                            "Security Log not supported\n");
> diff --git a/include/linux/ata.h b/include/linux/ata.h
> index e65ae4b2ed48..c7a353825450 100644
> --- a/include/linux/ata.h
> +++ b/include/linux/ata.h
> @@ -60,7 +60,8 @@ enum {
>       ATA_ID_FW_REV           = 23,
>       ATA_ID_PROD             = 27,
>       ATA_ID_MAX_MULTSECT     = 47,
> -     ATA_ID_DWORD_IO         = 48,
> +     ATA_ID_DWORD_IO         = 48,   /* before ATA-8 */
> +     ATA_ID_TRUSTED          = 48,   /* ATA-8 and later */
>       ATA_ID_CAPABILITY       = 49,
>       ATA_ID_OLD_PIO_MODES    = 51,
>       ATA_ID_OLD_DMA_MODES    = 52,
> @@ -889,6 +890,13 @@ static inline bool ata_id_has_dword_io(const u16 *id)
>       return id[ATA_ID_DWORD_IO] & (1 << 0);
>  }
>  
> +static inline bool ata_id_has_trusted(const u16 *id)
> +{
> +     if (ata_id_major_version(id) <= 7)
> +             return false;
> +     return id[ATA_ID_TRUSTED] & (1 << 0);
> +}
> +
>  static inline bool ata_id_has_unload(const u16 *id)
>  {
>       if (ata_id_major_version(id) >= 7 &&
> 

That works for me.

Tested-by: David Ahern <dsah...@gmail.com>

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