Hi, On Thu, Apr 30, 2020 at 9:47 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > Hi, > > On Thu, Apr 30, 2020 at 9:18 AM Daniel Thompson > <daniel.thompson@xxxxxxxxxx> wrote: > > > > Currently there is no guarantee that an earlycon will be initialized > > before kgdboc tries to adopt it. Almost the opposite: on systems > > with ACPI then if earlycon has no arguments then it is guaranteed that > > earlycon will not be initialized. > > > > This patch mitigates the problem by giving kgdboc_earlycon a second > > chance during console_init(). This isn't quite as good as stopping during > > early parameter parsing but it is still early in the kernel boot. > > > > Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> > > --- > > > > Notes: > > v2: Simplified, more robust, runs earlier, still has Doug's > > recent patchset as a prerequisite. What's not to like? > > > > More specifically, based on feedback from Doug Anderson, I > > have replaced the initial hacky implementation with a console > > initcall. > > > > I also made it defer more aggressively after realizing that both > > earlycon and kgdboc_earlycon are handled as early parameters > > (meaning I think the current approach relies on the ordering > > of drivers/tty/serial/Makefile to ensure the earlycon is enabled > > before kgdboc tries to adopt it). > > > > Finally, my apologies to Jason and kgdb ML folks, who are seeing > > this patch for the first time. I copied the original circulation > > list from a patch that wasn't kgdb related and forgot to update. > > > > drivers/tty/serial/kgdboc.c | 41 +++++++++++++++++++++++++++++++++++-- > > 1 file changed, 39 insertions(+), 2 deletions(-) > > Thanks, this looks great! > > Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Are you planning to rebase this patch atop what landed? It seems like a useful feature. If you want me to give a shot a rebasing, let me know! -Doug
