linux-kernel - Re: Serial port initialization broken on Armada 370/XP due to "serial: 8250_dw: Don't use UPF_FIXED

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:	Fri, 15 Mar 2013 13:24:52 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	Heikki Krogerus <heikki.krogerus@...ux.intel.com>
Cc:	Gregory CLEMENT <gregory.clement@...e-electrons.com>,
	Jamie Iles <jamie@...ieiles.com>,
	Jason Cooper <jason@...edaemon.net>,
	Andrew Lunn <andrew@...n.ch>,
	Thomas Petazzoni <thomas.petazzoni@...e-electrons.com>,
	Ezequiel Garcia <ezequiel.garcia@...e-electrons.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	linux-serial@...r.kernel.org
Subject: Re: Serial port initialization broken on Armada 370/XP due to
 "serial: 8250_dw: Don't use UPF_FIXED_TYPE"

On Thu, Feb 28, 2013 at 02:34:21PM +0200, Heikki Krogerus wrote:
> Hi,
> 
> On Thu, Feb 28, 2013 at 12:42:06PM +0100, Gregory CLEMENT wrote:
> > >> Would you agree with this kind of patch to fix the issue?
> > >>
> > >> diff --git a/drivers/tty/serial/8250/8250.c b/drivers/tty/serial/8250/8250.c
> > >> index e2ac25a..0b284c6 100644
> > >> --- a/drivers/tty/serial/8250/8250.c
> > >> +++ b/drivers/tty/serial/8250/8250.c
> > >> @@ -1119,7 +1119,7 @@ static void autoconfig(struct uart_8250_port *up, unsigned int probeflags)
> > >>         serial_out(up, UART_LCR, 0);
> > >>
> > >>         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
> > >> -       scratch = serial_in(up, UART_IIR) >> 6;
> > >> +       scratch = (serial_in(up, UART_IIR) & 0xFF) >> 6;
> > >>
> > >>         switch (scratch) {
> > >>         case 0:
> > > 
> > > Instead, can you test if it's enough for you to set the reg-io-width
> > > to 1 instead of 4:
> > 
> > Yes indeed it worked and it seems to be the correct description of my
> > hardware. So I will fix the dtsi file.
> > 
> > However isn't buggy to use a function as it returned a char whereas
> > it returns an int?
> 
> Yes, the driver should probable be cleaned.
> 
> It seems to be happening in quite a few places in 8250.c.
> autoconfig_16550a() has pretty much identical code in it, where
> UART_IIR is read to unsigned char and shifted without a mask.

Can someone send me the correct fix here, if they want it included in
3.9-final?

thanks,

greg k-h
--
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/