Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753805AbWKKVHO (ORCPT ); Sat, 11 Nov 2006 16:07:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754869AbWKKVHO (ORCPT ); Sat, 11 Nov 2006 16:07:14 -0500 Received: from smtp.osdl.org ([65.172.181.4]:36752 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1753805AbWKKVHM (ORCPT ); Sat, 11 Nov 2006 16:07:12 -0500 Date: Sat, 11 Nov 2006 13:06:56 -0800 From: Andrew Morton To: Russell King Cc: Marc Haber , linux-kernel@vger.kernel.org Subject: Re: ttyS0 not working any more, LSR safety check engaged Message-Id: <20061111130656.c9bae39f.akpm@osdl.org> In-Reply-To: <20061111153005.GA28277@flint.arm.linux.org.uk> References: <20061111114352.GA9206@torres.l21.ma.zugschlus.de> <20061111115016.GA24112@flint.arm.linux.org.uk> <20061111123455.GB9206@torres.l21.ma.zugschlus.de> <20061111153005.GA28277@flint.arm.linux.org.uk> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2314 Lines: 57 On Sat, 11 Nov 2006 15:30:05 +0000 Russell King wrote: > On Sat, Nov 11, 2006 at 01:34:55PM +0100, Marc Haber wrote: > > On Sat, Nov 11, 2006 at 11:50:16AM +0000, Russell King wrote: > > > Maybe something to do with PNP? Maybe ACPI? Both of those I know > > > nothing about, but I suggest that if you have PNP enabled, you > > > build and use the 8250_pnp module, even if your port is detected > > > by the legacy detection methods in 8250. > > > > How do I configure that? > > > > I have: > > ? ?<*> 8250/16550 and compatible serial support ? ? > > ? ?[*] Console on 8250/16550 and compatible serial port ? ? > > ? ?<*> 8250/16550 PCI device support ? ? > > ? ?<*> 8250/16550 PNP device support ? ? > > That's fine. > > > $ grep -i 'nov 11.*\(8250\|serial\|ttyS\|pnp\)' /var/log/syslog/syslog > > pnp: PnP ACPI init > > pnp: PnP ACPI: found 15 devices > > PnPBIOS: Disabled by ACPI PNP > > pnp: 00:0d: ioport range 0x4d0-0x4d1 has been reserved > > pnp: 00:0d: ioport range 0x1000-0x107f could not be reserved > > pnp: 00:0d: ioport range 0x1100-0x113f has been reserved > > pnp: 00:0d: ioport range 0x1200-0x121f has been reserved > > isapnp: Scanning for PnP cards... > > isapnp: No Plug & Play device found > > Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing disabled > > serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A > > ttyS0 detected via legacy ISA probes. > > > serial8250: ttyS2 at I/O 0x3e8 (irq = 4) is a 16550A > > ttyS2 detected via legacy ISA probes. > > > 00:02: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A > > ttyS0 detected via PNP device 00:02. > > > ttyS0: LSR safety check engaged! > > ttyS2: LSR safety check engaged! > > and then it mysteriously disappears on us. > > It's certainly a mystery. Suggest you git bisect to find the offending > change - I doubt it'll be serial/8250 itself. /proc/ioports and /proc/iomem might contain hints - can we see those please? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/