linux-kernel - Re: Question about TTY_DO_WRITE

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]

Message-ID: <Pine.LNX.4.64.0811201446380.21561@lxtpfaff.pcs.ditec.de>
Date:	Thu, 20 Nov 2008 15:09:43 +0100 (CET)
From:	Thomas Pfaff <tpfaff@....com>
To:	Alan Cox <alan@...rguk.ukuu.org.uk>
cc:	linux-kernel@...r.kernel.org
Subject: Re: Question about TTY_DO_WRITE_WAKEUP


On Thu, 20 Nov 2008, Alan Cox wrote:

> On Thu, 20 Nov 2008 11:06:19 +0100 (CET)
> Thomas Pfaff <tpfaff@....com> wrote:
> 
> > I have written a program that reads and writes data to the serial uart using 
> > async io.
> > Unfortunately it does not work properly because a SIGIO is never gerated when 
> > output becomes possible, the reason is that TTY_DO_WRITE_WAKEUP is not set for 
> > most of the tty drivers. After i set the bit in serial_core.c the program works 
> > as expected.
> > Now i wonder why TTY_DO_WRITE_WAKEUP is almost always disabled ?
> 
> Almost nobody uses SIGIO based I/O, especially on serial so I'm not
> actually suprised by this one. If you've got patches that fix it then
> please send them in.

Is the TTY_DO_WRITE_WAKEUP bit some kind of cruft that can be removed entirely 
or should i generate a patch for serial devices only ?

Removing it seems to be cleaner to me but i am unsure if it will break some 
other stuff.
--
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/