Thomas Gleixner wrote:

On Wed, 2007-07-25 at 13:42 -0600, Grant Likely wrote:

quoted

On 7/25/07, Thomas Gleixner [off-list ref] wrote:

quoted

The port lock needs to be dropped across the tty_flip_buffer call,
as it would lead to a deadlock with the spin_lock(&port->lock) in
uart_start()=20
=20
Uncovered by lockdep / preempt-rt
=20
Signed-off-by: Thomas Gleixner <redacted>

While you are at it 8=B0> ... the mpc5200-fec driver has serious =
problems with preempt-rt, similar to what the IBM emac had ....


Best regards,

Daniel Schnell.