Re: [PATCH 1/2 for 8.0] Add the port allocation logic for isa-serial devices.
On Thu, 13 Jan 2022, Michal Prívozník wrote:
> index 144ba4dd12..a8f41dc8c2 100644
> --- a/src/conf/domain_conf.h
> +++ b/src/conf/domain_conf.h
> @@ -1187,6 +1187,12 @@ typedef enum {
> VIR_DOMAIN_CHR_CONSOLE_TARGET_TYPE_LAST
> } virDomainChrConsoleTargetType;
>
> +/*
> + * The value of VIR_MAX_ISA_SERIAL_PORTS corresponds to MAX_ISA_SERIAL_PORTS
> + * set in qemu code base.
We prefer upper case spelling of QEMU. And it's been a long time since
I've last booted up my machine with ISA, but IIRC it could only have 4
COM ports, so maybe the limit doesn't come from QEMU really but BIOS of
that time? What I'm trying to say is, if this is a limit shared across
other hypervisors then it can live under src/conf/ but if isn't shared
then it has to go under hypervisor specific dir (src/qemu/ in this case).
I'm just going to assume the limit is shared and not QEMU specific.
Maybe I read this wrong but I interpreted this commit message in QEMU
repo to mean that the limitation is qemu specific :
commit def337ffda34d331404bd7f1a42726b71500df22
Author: Peter Maydell <peter.maydell(a)linaro.org>
Date: Fri Apr 20 15:52:46 2018 +0100
serial-isa: Use MAX_ISA_SERIAL_PORTS instead of MAX_SERIAL_PORTS
The ISA serial port handling in serial-isa.c imposes a limit
of 4 serial ports. This is because we only know of 4 IO port
and IRQ settings for them, and is unrelated to the generic
MAX_SERIAL_PORTS limit, though they happen to both be set at
4 currently.
Use a new MAX_ISA_SERIAL_PORTS wherever that is the correct
limit to be checking against.
Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug(a)amsat.org>
Reviewed-by: Thomas Huth <thuth(a)redhat.com>
Tested-by: Philippe Mathieu-Daudé <f4bug(a)amsat.org>
Message-id: 20180420145249.32435-11-peter.maydell(a)linaro.org