Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> writes: > On Thu, Jan 28, 2021 at 05:22:44PM +0000, Mans Rullgard wrote: >> On systems that do not have the traditional PC ISA serial ports, the >> 8250 driver still creates non-functional device nodes. This change >> makes only ports that actually exist (PCI, DT, ...) get device nodes. >> >> Signed-off-by: Mans Rullgard <mans@xxxxxxxxx> >> --- >> drivers/tty/serial/8250/8250_core.c | 26 ++++++++++++++++++++------ >> drivers/tty/serial/8250/Kconfig | 5 +++++ >> 2 files changed, 25 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c >> index cae61d1ebec5..49695dd3677c 100644 >> --- a/drivers/tty/serial/8250/8250_core.c >> +++ b/drivers/tty/serial/8250/8250_core.c >> @@ -555,6 +555,7 @@ static void __init serial8250_isa_init_ports(void) >> } >> } >> >> +#ifdef CONFIG_SERIAL_8250_ISA > > This is just making a mess of the code. It was already a mess. > To do this right, pull the isa code out into a separate file and put > the #ifdef in a .h file, so we can properly maintain and support this > code over time. This change as-is is not going to make that any > easier :( I might put in that effort if there's a reasonable chance this change will be accepted. If it's going to be rejected regardless, I'd rather not waste my time. >> +config SERIAL_8250_ISA >> + bool "8250/16550 ISA device support" if EXPERT > > So, no one will set this? I followed the pattern of the existing SERIAL_8250_PNP option. Was that a mistake? How would you prefer it? > What userspace visable change will be caused by this? There won't be /dev/ttyS devices for ports that don't exist. > Will ports get renumbered? Not if they had predictable numbers to begin with. > What harm is this causing systems today without this change? It means I have to somehow maintain a separate list of which ports are real and which should be ignored, or else try to distinguish real errors from those caused by trying to access the bogus ports. -- Måns Rullgård
