On 14 November 2017 at 12:02, James Hogan <james.hogan@xxxxxxxx> wrote: > On Sun, Oct 29, 2017 at 04:27:21PM +0100, Jonas Gorski wrote: >> Since commit aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt >> trigger I/F of FIFO buffers"), the port's default FCR value isn't used >> in serial8250_do_set_termios anymore, but copied over once in >> serial8250_config_port and then modified as needed. >> >> Unfortunately, serial8250_config_port will never be called if the port >> is shared between kernel and userspace, and the port's flag doesn't have >> UPF_BOOT_AUTOCONF, which would trigger a serial8250_config_port as well. >> >> This causes garbled output from userspace: >> >> [ 5.220000] random: procd urandom read with 49 bits of entropy available >> ers >> [kee >> >> Fix this by forcing it to be configured on boot, resulting in the >> expected output: >> >> [ 5.250000] random: procd urandom read with 50 bits of entropy available >> Press the [f] key and hit [enter] to enter failsafe mode >> Press the [1], [2], [3] or [4] key and hit [enter] to select the debug level >> >> Fixes: aef9a7bd9b67 ("serial/uart/8250: Add tunable RX interrupt trigger I/F of FIFO buffers") >> Signed-off-by: Jonas Gorski <jonas.gorski@xxxxxxxxx> >> --- >> I'm not sure if this is just AR7's issue, or if this points to a general >> issue for UARTs used as kernel console and login console with the "fixed" >> commit. > > Thanks. Given nobody seems to have objected, I've applied to my > mips-fixes branch, with stable tag for 3.17+. Hmm, I don't see it in https://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips.git/log/?h=mips-fixes - did you maybe forget to push? Regards Jonas