From: Petr Mladek <pmladek@suse.com>
To: kexec@lists.infradead.org
Subject: [PATCH 19/30] panic: Add the panic hypervisor notifier list
Date: Mon, 16 May 2022 16:01:57 +0200 [thread overview]
Message-ID: <YoJZVZl/MH0KiE/J@alley> (raw)
In-Reply-To: <20220427224924.592546-20-gpiccoli@igalia.com>
On Wed 2022-04-27 19:49:13, Guilherme G. Piccoli wrote:
> The goal of this new panic notifier is to allow its users to register
> callbacks to run very early in the panic path. This aims hypervisor/FW
> notification mechanisms as well as simple LED functions, and any other
> simple and safe mechanism that should run early in the panic path; more
> dangerous callbacks should execute later.
>
> For now, the patch is almost a no-op (although it changes a bit the
> ordering in which some panic notifiers are executed). In a subsequent
> patch, the panic path will be refactored, then the panic hypervisor
> notifiers will effectively run very early in the panic path.
>
> We also defer documenting it all properly in the subsequent refactor
> patch. While at it, we removed some useless header inclusions and
> fixed some notifiers return too (by using the standard NOTIFY_DONE).
> --- 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.
>
> return 0;
> }
> diff --git a/arch/mips/sgi-ip32/ip32-reset.c b/arch/mips/sgi-ip32/ip32-reset.c
> index 18d1c115cd53..9ee1302c9d13 100644
> --- 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".
>
> return 0;
> }
> --- 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.
>
> printk(KERN_INFO "gsmi version " DRIVER_VERSION " loaded\n");
> --- a/drivers/leds/trigger/ledtrig-activity.c
> +++ b/drivers/leds/trigger/ledtrig-activity.c
> @@ -247,7 +247,7 @@ static int __init activity_init(void)
> int rc = led_trigger_register(&activity_led_trigger);
>
> if (!rc) {
> - atomic_notifier_chain_register(&panic_notifier_list,
> + atomic_notifier_chain_register(&panic_hypervisor_list,
> &activity_panic_nb);
The notifier is trivial. It just sets a variable.
But still, it is about blinking and should be done
in the last "loop" list.
> register_reboot_notifier(&activity_reboot_nb);
> }
> --- a/drivers/leds/trigger/ledtrig-heartbeat.c
> +++ b/drivers/leds/trigger/ledtrig-heartbeat.c
> @@ -190,7 +190,7 @@ static int __init heartbeat_trig_init(void)
> int rc = led_trigger_register(&heartbeat_led_trigger);
>
> if (!rc) {
> - atomic_notifier_chain_register(&panic_notifier_list,
> + atomic_notifier_chain_register(&panic_hypervisor_list,
> &heartbeat_panic_nb);
Same here. Blinking => loop list.
> register_reboot_notifier(&heartbeat_reboot_nb);
> }
> diff --git a/drivers/misc/bcm-vk/bcm_vk_dev.c b/drivers/misc/bcm-vk/bcm_vk_dev.c
> index a16b99bdaa13..d9d5199cdb2b 100644
> --- a/drivers/misc/bcm-vk/bcm_vk_dev.c
> +++ b/drivers/misc/bcm-vk/bcm_vk_dev.c
> @@ -1446,7 +1446,7 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>
> /* register for panic notifier */
> vk->panic_nb.notifier_call = bcm_vk_on_panic;
> - err = atomic_notifier_chain_register(&panic_notifier_list,
> + err = atomic_notifier_chain_register(&panic_hypervisor_list,
> &vk->panic_nb);
It seems to reset some hardware or so. IMHO, it should go into the
pre-reboot list.
> if (err) {
> dev_err(dev, "Fail to register panic notifier\n");
> --- a/drivers/power/reset/ltc2952-poweroff.c
> +++ b/drivers/power/reset/ltc2952-poweroff.c
> @@ -279,7 +279,7 @@ static int ltc2952_poweroff_probe(struct platform_device *pdev)
> pm_power_off = ltc2952_poweroff_kill;
>
> data->panic_notifier.notifier_call = ltc2952_poweroff_notify_panic;
> - atomic_notifier_chain_register(&panic_notifier_list,
> + atomic_notifier_chain_register(&panic_hypervisor_list,
> &data->panic_notifier);
I looks like this somehow triggers the reboot. IMHO, it should go
into the pre_reboot list.
> dev_info(&pdev->dev, "probe successful\n");
>
> --- a/drivers/soc/bcm/brcmstb/pm/pm-arm.c
> +++ b/drivers/soc/bcm/brcmstb/pm/pm-arm.c
> @@ -814,7 +814,7 @@ static int brcmstb_pm_probe(struct platform_device *pdev)
> goto out;
> }
>
> - atomic_notifier_chain_register(&panic_notifier_list,
> + atomic_notifier_chain_register(&panic_hypervisor_list,
> &brcmstb_pm_panic_nb);
I am not sure about this one. It instruct some HW to preserve DRAM.
IMHO, it better fits into pre_reboot category but I do not have
strong opinion.
>
> pm_power_off = brcmstb_pm_poweroff;
Best Regards,
Petr
next prev parent reply other threads:[~2022-05-16 14:01 UTC|newest]
Thread overview: 178+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-27 22:48 [PATCH 00/30] The panic notifiers refactor Guilherme G. Piccoli
2022-04-27 22:48 ` [PATCH 01/30] x86/crash, reboot: Avoid re-disabling VMX in all CPUs on crash/restart Guilherme G. Piccoli
2022-05-09 12:32 ` [PATCH 01/30] x86/crash,reboot: " Guilherme G. Piccoli
2022-05-09 15:52 ` Sean Christopherson
2022-05-10 20:11 ` Guilherme G. Piccoli
2022-04-27 22:48 ` [PATCH 02/30] ARM: kexec: Disable IRQs/FIQs also on crash CPUs shutdown path Guilherme G. Piccoli
2022-04-29 16:26 ` Michael Kelley
2022-04-29 18:20 ` Marc Zyngier
2022-04-29 21:38 ` Guilherme G. Piccoli
2022-04-29 21:45 ` Russell King
2022-04-29 21:56 ` Guilherme G. Piccoli
2022-04-29 22:00 ` Marc Zyngier
2022-04-27 22:48 ` [PATCH 03/30] notifier: Add panic notifiers info and purge trailing whitespaces Guilherme G. Piccoli
2022-04-27 22:48 ` [PATCH 04/30] firmware: google: Convert regular spinlock into trylock on panic path Guilherme G. Piccoli
2022-05-03 18:03 ` Evan Green
2022-05-03 19:12 ` Guilherme G. Piccoli
2022-05-03 21:56 ` Evan Green
2022-05-04 12:45 ` Guilherme G. Piccoli
2022-05-10 11:38 ` Petr Mladek
2022-05-10 13:04 ` Guilherme G. Piccoli
2022-05-10 17:20 ` Steven Rostedt
2022-05-10 19:40 ` John Ogness
2022-05-11 11:13 ` Petr Mladek
2022-04-27 22:48 ` [PATCH 05/30] misc/pvpanic: " Guilherme G. Piccoli
2022-05-10 12:14 ` Petr Mladek
2022-05-10 13:00 ` Guilherme G. Piccoli
2022-05-17 10:58 ` Petr Mladek
2022-05-17 13:03 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 06/30] soc: bcm: brcmstb: Document panic notifier action and remove useless header Guilherme G. Piccoli
2022-05-02 15:38 ` Florian Fainelli
2022-05-02 15:47 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 07/30] mips: ip22: Reword PANICED to PANICKED " Guilherme G. Piccoli
2022-05-04 20:32 ` Thomas Bogendoerfer
2022-05-04 21:26 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 08/30] powerpc/setup: Refactor/untangle panic notifiers Guilherme G. Piccoli
2022-05-05 18:55 ` Hari Bathini
2022-05-05 19:28 ` Guilherme G. Piccoli
2022-05-09 12:50 ` Guilherme G. Piccoli
2022-05-10 13:53 ` Michael Ellerman
2022-05-10 14:10 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 09/30] coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifier Guilherme G. Piccoli
2022-04-28 8:11 ` Suzuki K Poulose
2022-04-29 14:01 ` Guilherme G. Piccoli
2022-05-09 13:09 ` Guilherme G. Piccoli
2022-05-09 16:14 ` Suzuki K Poulose
2022-05-09 16:26 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 10/30] alpha: Clean-up the panic notifier code Guilherme G. Piccoli
2022-05-09 14:13 ` Guilherme G. Piccoli
2022-05-10 14:16 ` Petr Mladek
2022-05-11 20:10 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 11/30] um: Improve panic notifiers consistency and ordering Guilherme G. Piccoli
2022-05-10 14:28 ` Petr Mladek
2022-05-11 20:22 ` Guilherme G. Piccoli
2022-05-13 14:44 ` Johannes Berg
2022-05-15 22:12 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 12/30] parisc: Replace regular spinlock with spin_trylock on panic path Guilherme G. Piccoli
2022-04-28 16:55 ` Helge Deller
2022-04-29 14:34 ` Guilherme G. Piccoli
2022-05-23 20:40 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 13/30] s390/consoles: Improve panic notifiers reliability Guilherme G. Piccoli
2022-04-29 18:46 ` Heiko Carstens
2022-04-29 19:31 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 14/30] panic: Properly identify the panic event to the notifiers' callbacks Guilherme G. Piccoli
2022-05-10 15:16 ` Petr Mladek
2022-05-10 16:16 ` Guilherme G. Piccoli
2022-05-17 13:11 ` Petr Mladek
2022-05-17 15:19 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 15/30] bus: brcmstb_gisb: Clean-up panic/die notifiers Guilherme G. Piccoli
2022-05-02 15:38 ` Florian Fainelli
2022-05-02 15:50 ` Guilherme G. Piccoli
2022-05-10 15:28 ` Petr Mladek
2022-05-17 15:32 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 16/30] drivers/hv/vmbus, video/hyperv_fb: Untangle and refactor Hyper-V panic notifiers Guilherme G. Piccoli
2022-04-29 17:16 ` Michael Kelley
2022-04-29 22:35 ` Guilherme G. Piccoli
2022-05-03 18:13 ` Michael Kelley
2022-05-03 18:57 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 17/30] tracing: Improve panic/die notifiers Guilherme G. Piccoli
2022-04-29 9:22 ` Sergei Shtylyov
2022-04-29 13:23 ` Steven Rostedt
2022-04-29 13:46 ` Guilherme G. Piccoli
2022-04-29 13:56 ` Steven Rostedt
2022-04-29 14:44 ` Guilherme G. Piccoli
2022-05-11 11:45 ` Petr Mladek
2022-05-17 15:33 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 18/30] notifier: Show function names on notifier routines if DEBUG_NOTIFIERS is set Guilherme G. Piccoli
2022-04-28 1:01 ` Xiaoming Ni
2022-04-29 19:38 ` Guilherme G. Piccoli
2022-05-10 17:29 ` Steven Rostedt
2022-05-16 16:14 ` Guilherme G. Piccoli
2022-04-29 16:27 ` Michael Kelley
2022-04-27 22:49 ` [PATCH 19/30] panic: Add the panic hypervisor notifier list Guilherme G. Piccoli
2022-04-29 17:30 ` Michael Kelley
2022-04-29 18:04 ` Guilherme G. Piccoli
2022-05-03 17:44 ` Michael Kelley
2022-05-03 17:56 ` Guilherme G. Piccoli
2022-05-16 14:01 ` Petr Mladek [this message]
2022-05-16 15:06 ` Guilherme G. Piccoli
2022-05-16 16:02 ` Evan Green
2022-05-17 13:28 ` Petr Mladek
2022-05-17 16:37 ` Guilherme G. Piccoli
[not found] ` <YoShZVYNAdvvjb7z@alley>
2022-05-18 13:24 ` Guilherme G. Piccoli
2022-05-17 13:57 ` Petr Mladek
2022-05-17 16:42 ` Guilherme G. Piccoli
2022-05-18 7:38 ` Petr Mladek
2022-05-18 13:09 ` Guilherme G. Piccoli
2022-05-18 22:17 ` Scott Branden
2022-05-19 12:19 ` Guilherme G. Piccoli
2022-05-19 19:20 ` Scott Branden
2022-05-23 14:56 ` Guilherme G. Piccoli
2022-05-24 8:04 ` Petr Mladek
2022-05-18 7:58 ` Petr Mladek
2022-05-18 13:16 ` Guilherme G. Piccoli
2022-05-19 7:03 ` Petr Mladek
2022-05-19 12:07 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 20/30] panic: Add the panic informational " Guilherme G. Piccoli
2022-04-27 23:49 ` Paul E. McKenney
2022-04-28 8:14 ` Suzuki K Poulose
2022-04-29 14:50 ` Guilherme G. Piccoli
2022-05-16 14:11 ` Petr Mladek
2022-05-16 14:28 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 21/30] panic: Introduce the panic pre-reboot " Guilherme G. Piccoli
2022-04-28 14:13 ` Alex Elder
2022-04-28 16:26 ` Corey Minyard
2022-04-29 15:18 ` Guilherme G. Piccoli
2022-04-29 16:04 ` Max Filippov
2022-04-29 19:34 ` Guilherme G. Piccoli
2022-05-16 14:33 ` Petr Mladek
2022-05-16 16:05 ` Guilherme G. Piccoli
2022-05-16 16:18 ` Luck, Tony
2022-05-16 16:33 ` Guilherme G. Piccoli
2022-05-17 14:11 ` Petr Mladek
2022-05-17 16:45 ` Guilherme G. Piccoli
2022-05-17 17:02 ` Luck, Tony
2022-05-17 18:12 ` Guilherme G. Piccoli
2022-05-17 19:07 ` Luck, Tony
2022-04-27 22:49 ` [PATCH 22/30] panic: Introduce the panic post-reboot " Guilherme G. Piccoli
2022-05-09 14:16 ` Guilherme G. Piccoli
2022-05-11 16:45 ` Heiko Carstens
2022-05-11 19:58 ` Guilherme G. Piccoli
2022-05-16 14:45 ` Petr Mladek
2022-05-16 16:08 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 23/30] printk: kmsg_dump: Introduce helper to inform number of dumpers Guilherme G. Piccoli
2022-05-10 17:40 ` Steven Rostedt
2022-05-11 20:03 ` Guilherme G. Piccoli
2022-05-16 14:50 ` Petr Mladek
2022-05-16 16:09 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 24/30] panic: Refactor the panic path Guilherme G. Piccoli
2022-04-28 0:28 ` Randy Dunlap
2022-04-29 16:04 ` Guilherme G. Piccoli
2022-05-09 14:25 ` Guilherme G. Piccoli
2022-04-29 17:53 ` Michael Kelley
2022-04-29 20:38 ` Guilherme G. Piccoli
2022-05-03 17:31 ` Michael Kelley
2022-05-03 18:06 ` Guilherme G. Piccoli
2022-05-09 15:16 ` d.hatayama
2022-05-09 16:39 ` Guilherme G. Piccoli
2022-05-12 14:03 ` Petr Mladek
2022-05-15 22:47 ` Guilherme G. Piccoli
2022-05-16 10:21 ` Petr Mladek
2022-05-16 16:32 ` Guilherme G. Piccoli
2022-05-19 23:45 ` Baoquan He
2022-05-20 11:23 ` Guilherme G. Piccoli
2022-05-24 8:01 ` Petr Mladek
2022-05-24 10:18 ` Baoquan He
2022-05-24 8:32 ` Baoquan He
2022-05-24 14:44 ` Eric W. Biederman
2022-05-26 16:25 ` Guilherme G. Piccoli
2022-06-14 14:36 ` Petr Mladek
2022-06-15 9:36 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 25/30] panic, printk: Add console flush parameter and convert panic_print to a notifier Guilherme G. Piccoli
2022-05-16 14:56 ` Petr Mladek
2022-05-16 16:11 ` Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 26/30] Drivers: hv: Do not force all panic notifiers to execute before kdump Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 27/30] powerpc: " Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 28/30] panic: Unexport crash_kexec_post_notifiers Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 29/30] powerpc: ps3, pseries: Avoid duplicate call to kmsg_dump() on panic Guilherme G. Piccoli
2022-04-27 22:49 ` [PATCH 30/30] um: Avoid duplicate call to kmsg_dump() Guilherme G. Piccoli
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