linux-kernel - Re: [PATCH 2/2] MEMSTICK: Add driver for Ricoh R5C592 Card reader.

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:	Sun, 08 Aug 2010 23:08:59 +0300
From:	Maxim Levitsky <maximlevitsky@...il.com>
To:	Alex Dubov <oakad@...oo.com>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] MEMSTICK: Add driver for Ricoh R5C592 Card reader.

On Sun, 2010-08-08 at 18:07 +0300, Maxim Levitsky wrote: 
> On Sun, 2010-08-08 at 07:26 -0700, Alex Dubov wrote: 
> > > Hi,
> > > 
> > > I have few more questions about memsticks.
> > > 
> > > First of all, I need an explanation of overwrite flag.
> > > You already explained it to me once, but I still not sure
> > > about few
> > > things.
> > 
> > Overwrite register can be accessed either as part of extra data access
> > or separately (CP_OVERWRITE access mode).
> > 
Few more questions I gathered today.

I currently assume that if I set req->need_card_int, the driver will
wait till device raises MEMSTICK_INT_CED regardless of serial/parallel
mode. This bit is always available on serial line.
Is that OK to assume?

Another thing that I want to ask is about writes to overwrite/managment
flag.
Common sense tells me that I can write the flash many times, but write
can only clear bits. Therefore if I write 0xFF, this just means do
nothing.
Probably same applies to data content, but that isn't much of the use.
Thats why I see that default (good) value of bits in overwrite flag is
1.
This is correct I assume?

Another interesting thing I observed was that MEMSTICK_INT_ERR can mean
a correctable error,  therefore it shouldn't alone  reject read/write of
a sector. (I think that it means that one of
MEMSTICK_STATUS1_UCFG..MEMSTICK_STATUS1_DTER is set)
Same question about this.

Best regards,
Maxim Levitsky

--
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/