linux-kernel - Re: [PATCH] ide: Fix ata_id_has_dword_io to return DWORD I/O support properly

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 18 Dec 2008 20:24:56 +0300
From:	Sergei Shtylyov <sshtylyov@...mvista.com>
To:	Jeff Garzik <jeff@...zik.org>
Cc:	Mario Schwalbe <schwalbe@....tu-dresden.de>,
	Bartlomiej Zolnierkiewicz <bzolnier@...il.com>,
	linux-kernel@...r.kernel.org,
	Linux IDE mailing list <linux-ide@...r.kernel.org>
Subject: Re: [PATCH] ide: Fix ata_id_has_dword_io to return DWORD I/O support
 properly

Hello.

Jeff Garzik wrote:

>> This patch fixes ata_id_has_dword_io to return 1 (supported) if
>> the drive is compliant to ATA2 or newer and evaluates the config
>> word for older drives.

>> Signed-off-by: Mario Schwalbe <schwalbe@....tu-dresden.de>

>> diff --git a/include/linux/ata.h b/include/linux/ata.h
>> index a53318b..d0d6a9c 100644
>> --- a/include/linux/ata.h
>> +++ b/include/linux/ata.h
>> @@ -700,12 +700,12 @@ static inline int ata_id_has_tpm(const u16 *id)

>>  static inline int ata_id_has_dword_io(const u16 *id)
>>  {
>> -    /* ATA 8 reuses this flag for "trusted" computing */
>> -    if (ata_id_major_version(id) > 7)
>> -        return 0;
>> -    if (id[ATA_ID_DWORD_IO] & (1 << 0))
>> -        return 1;
>> -    return 0;
>> +    /* This flag is defined up to ATA1 and deprecated since then
>> +       (ATA 8 reuses this flag for "trusted" computing). */
>> +    if (ata_id_major_version(id) <= 1)
>> +        return (id[ATA_ID_DWORD_IO] & (1 << 0)) != 0;
>> +    /* later revision drives support DWORD I/O just fine */
>> +    return 1;

> This seems like a risky assumption...

    Not at all, I think. It's total mystery how "DWORD I/O" could've been even 
(not) supported by a *drive* at all. Support of "DWORD I/O" is a property of 
the PATA controller. Frankly speaking, I don't think that this function is at 
all useful...

>     Jeff

MBR, Sergei
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/