On Mon, May 16, 2022 at 8:07 AM Guilherme G. Piccoli <gpiccoli@xxxxxxxxxx> wrote: > > Thanks for the review! > > I agree with the blinking stuff, I can rework and add all LED/blinking > stuff into the loop list, it does make sense. I'll comment a bit in the > others below... > > On 16/05/2022 11:01, Petr Mladek wrote: > > [...] > >> --- a/arch/mips/sgi-ip22/ip22-reset.c > >> +++ b/arch/mips/sgi-ip22/ip22-reset.c > >> @@ -195,7 +195,7 @@ static int __init reboot_setup(void) > >> } > >> > >> timer_setup(&blink_timer, blink_timeout, 0); > >> - atomic_notifier_chain_register(&panic_notifier_list, &panic_block); > >> + atomic_notifier_chain_register(&panic_hypervisor_list, &panic_block); > > > > This notifier enables blinking. It is not much safe. It calls > > mod_timer() that takes a lock internally. > > > > This kind of functionality should go into the last list called > > before panic() enters the infinite loop. IMHO, all the blinking > > stuff should go there. > > [...] > >> --- a/arch/mips/sgi-ip32/ip32-reset.c > >> +++ b/arch/mips/sgi-ip32/ip32-reset.c > >> @@ -145,7 +144,7 @@ static __init int ip32_reboot_setup(void) > >> pm_power_off = ip32_machine_halt; > >> > >> timer_setup(&blink_timer, blink_timeout, 0); > >> - atomic_notifier_chain_register(&panic_notifier_list, &panic_block); > >> + atomic_notifier_chain_register(&panic_hypervisor_list, &panic_block); > > > > Same here. Should be done only before the "loop". > > [...] > > Ack. > > > >> --- a/drivers/firmware/google/gsmi.c > >> +++ b/drivers/firmware/google/gsmi.c > >> @@ -1034,7 +1034,7 @@ static __init int gsmi_init(void) > >> > >> register_reboot_notifier(&gsmi_reboot_notifier); > >> register_die_notifier(&gsmi_die_notifier); > >> - atomic_notifier_chain_register(&panic_notifier_list, > >> + atomic_notifier_chain_register(&panic_hypervisor_list, > >> &gsmi_panic_notifier); > > > > I am not sure about this one. It looks like some logging or > > pre_reboot stuff. > > > > Disagree here. I'm looping Google maintainers, so they can comment. > (CCed Evan, David, Julius) > > This notifier is clearly a hypervisor notification mechanism. I've fixed > a locking stuff there (in previous patch), I feel it's low-risk but even > if it's mid-risk, the class of such callback remains a perfect fit with > the hypervisor list IMHO. This logs a panic to our "eventlog", a tiny logging area in SPI flash for critical and power-related events. In some cases this ends up being the only clue we get in a Chromebook feedback report that a panic occurred, so from my perspective moving it to the front of the line seems like a good idea. -Evan
