linux-kernel - Re: PROBLEM: Sun Ultra 60 hangs on boot since Linux 6.8

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: <20240322090657.GD5132@atomide.com>
Date: Fri, 22 Mar 2024 11:06:57 +0200
From: Tony Lindgren <tony@...mide.com>
To: Nick Bowler <nbowler@...conx.ca>
Cc: linux-kernel@...r.kernel.org, sparclinux@...r.kernel.org,
	regressions@...ts.linux.dev, linux-serial@...r.kernel.org
Subject: Re: PROBLEM: Sun Ultra 60 hangs on boot since Linux 6.8

* Tony Lindgren <tony@...mide.com> [240322 08:48]:
> * Nick Bowler <nbowler@...conx.ca> [240322 06:36]:
> > On 2024-03-22 01:15, Tony Lindgren wrote:
> > > Can you please test if the following change to add back the check for
> > > !pm_runtime_active() is enough to fix the issue?
> > 
> > I applied the below patch on top of 6.8 and unfortunately it does _not_
> > fix the problem (no obvious change in behaviour).
> 
> Hmm OK thanks for testing. I'll take a look and see if I can debug this
> with qemu sparc as I no longer have any sparc boxes around.

I can't reproduce this on qemu-system-sparc64, probably as it does not use
the sunsab driver.

I noticed something though, I think we need to test for the port device
instead for being runtime PM enabled.

Can you please test if the updated patch below make things work again?

Regards,

Tony

8< -------------------
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -156,7 +156,7 @@ static void __uart_start(struct uart_state *state)
 	 * enabled, serial_port_runtime_resume() calls start_tx() again
 	 * after enabling the device.
 	 */
-	if (pm_runtime_active(&port_dev->dev))
+	if (!pm_runtime_enabled(port->dev) || pm_runtime_active(&port_dev->dev))
 		port->ops->start_tx(port);
 	pm_runtime_mark_last_busy(&port_dev->dev);
 	pm_runtime_put_autosuspend(&port_dev->dev);
-- 
2.44.0