[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <72eceb0c-8654-6c63-f1c4-c9374f99dfb3@collabora.com>
Date: Tue, 24 May 2022 23:16:41 +0300
From: Dmitry Osipenko <dmitry.osipenko@...labora.com>
To: Geert Uytterhoeven <geert@...ux-m68k.org>
Cc: Thierry Reding <thierry.reding@...il.com>,
Jonathan Hunter <jonathanh@...dia.com>,
Russell King <linux@...linux.org.uk>,
Catalin Marinas <catalin.marinas@....com>,
Will Deacon <will@...nel.org>, Guo Ren <guoren@...nel.org>,
Greg Ungerer <gerg@...ux-m68k.org>,
Joshua Thompson <funaho@...ai.org>,
Thomas Bogendoerfer <tsbogend@...ha.franken.de>,
Sebastian Reichel <sre@...nel.org>,
Linus Walleij <linus.walleij@...aro.org>,
Philipp Zabel <p.zabel@...gutronix.de>,
Greentime Hu <green.hu@...il.com>,
Vincent Chen <deanbo422@...il.com>,
"James E.J. Bottomley" <James.Bottomley@...senpartnership.com>,
Helge Deller <deller@....de>,
Michael Ellerman <mpe@...erman.id.au>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
Paul Mackerras <paulus@...ba.org>,
Paul Walmsley <paul.walmsley@...ive.com>,
Palmer Dabbelt <palmer@...belt.com>,
Albert Ou <aou@...s.berkeley.edu>,
Yoshinori Sato <ysato@...rs.sourceforge.jp>,
Rich Felker <dalias@...c.org>,
Thomas Gleixner <tglx@...utronix.de>,
Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
Dave Hansen <dave.hansen@...ux.intel.com>,
the arch/x86 maintainers <x86@...nel.org>,
"H. Peter Anvin" <hpa@...or.com>,
Boris Ostrovsky <boris.ostrovsky@...cle.com>,
Juergen Gross <jgross@...e.com>,
Stefano Stabellini <sstabellini@...nel.org>,
"Rafael J. Wysocki" <rafael@...nel.org>,
Len Brown <lenb@...nel.org>,
Santosh Shilimkar <ssantosh@...nel.org>,
Krzysztof Kozlowski <krzk@...nel.org>,
Liam Girdwood <lgirdwood@...il.com>,
Mark Brown <broonie@...nel.org>, Pavel Machek <pavel@....cz>,
Lee Jones <lee.jones@...aro.org>,
Andrew Morton <akpm@...ux-foundation.org>,
Guenter Roeck <linux@...ck-us.net>,
Daniel Lezcano <daniel.lezcano@...aro.org>,
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
Ulf Hansson <ulf.hansson@...aro.org>,
Michał Mirosław <mirq-linux@...e.qmqm.pl>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
linux-csky@...r.kernel.org,
"linux-ia64@...r.kernel.org" <linux-ia64@...r.kernel.org>,
linux-m68k <linux-m68k@...ts.linux-m68k.org>,
"open list:BROADCOM NVRAM DRIVER" <linux-mips@...r.kernel.org>,
Parisc List <linux-parisc@...r.kernel.org>,
linux-riscv <linux-riscv@...ts.infradead.org>,
Linux-sh list <linux-sh@...r.kernel.org>,
xen-devel@...ts.xenproject.org,
ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
Linux PM list <linux-pm@...r.kernel.org>,
linux-tegra <linux-tegra@...r.kernel.org>,
Linux-Renesas <linux-renesas-soc@...r.kernel.org>
Subject: Re: [PATCH v8 07/27] kernel/reboot: Add kernel_can_power_off()
On 5/24/22 18:03, Geert Uytterhoeven wrote:
> Hi Dmitry,
>
> On Tue, May 24, 2022 at 3:41 PM Dmitry Osipenko
> <dmitry.osipenko@...labora.com> wrote:
>> On 5/24/22 16:14, Geert Uytterhoeven wrote:
>>> On Tue, May 10, 2022 at 1:33 AM Dmitry Osipenko
>>> <dmitry.osipenko@...labora.com> wrote:
>>>> Add kernel_can_power_off() helper that replaces open-coded checks of
>>>> the global pm_power_off variable. This is a necessary step towards
>>>> supporting chained power-off handlers.
>>>>
>>>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@...labora.com>
>>>
>>> Thanks for your patch, which is now commit 0e2110d2e910e44c
>>> ("kernel/reboot: Add kernel_can_power_off()") in pm/linux-next.
>>>
>>> This causes the "poweroff" command (Debian nfsroot) to no longer
>>> cleanly halt the system on arm32 systems, but fail with a panic
>>> instead:
>>>
>>> -reboot: System halted
>>> +reboot: Power down
>>> +Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000000
>>> +CPU: 0 PID: 1 Comm: systemd-shutdow Not tainted
>>> 5.18.0-rc7-shmobile-00007-g0e2110d2e910 #1274
>>> +Hardware name: Generic R-Car Gen2 (Flattened Device Tree)
>>> + unwind_backtrace from show_stack+0x10/0x14
>>> + show_stack from dump_stack_lvl+0x40/0x4c
>>> + dump_stack_lvl from panic+0xf4/0x330
>>> + panic from do_exit+0x1c8/0x8e4
>>> + do_exit from __do_sys_reboot+0x174/0x1fc
>>> + __do_sys_reboot from ret_fast_syscall+0x0/0x54
>>> +Exception stack(0xf0815fa8 to 0xf0815ff0)
>>> +5fa0: 004e6954 00000000 fee1dead 28121969 4321fedc f0d94600
>>> +5fc0: 004e6954 00000000 00000000 00000058 befa0c78 00000000 befa0c10 004e56f8
>>> +5fe0: 00000058 befa0b6c b6ec8d45 b6e4a746
>>> +---[ end Kernel panic - not syncing: Attempted to kill init!
>>> exitcode=0x00000000 ]---
>>>
>>> On arm64, "poweroff" causes a clean "reboot: Power down" before/after.
>>>
>>> On both arm32 and arm64, the same handlers are registered:
>>> - SYS_OFF_MODE_POWER_OFF_PREPARE: legacy_pm_power_off_prepare
>>> - SYS_OFF_MODE_POWER_OFF: legacy_pm_power_off
>>>
>>> On both arm32 and arm64, legacy_pm_power_off_prepare() is called.
>>> On both arm32 and arm64, legacy_pm_power_off() does not seem to
>>> be called.
>>>
>>> On arm32, both pm_power_off_prepare and pm_power_off are NULL.
>>> On arm64, pm_power_off_prepare is NULL, and
>>> pm_power_off is psci_sys_poweroff.
>>>
>>> Do you have a clue?
>>> Thanks!
>>
>> Thank you, Geert! I see the problem, the kernel_can_power_off() checks whether power-off handler is registered, but it's always registered because legacy_pm_power_off is registered unconditionally. So it causes trouble for platforms that don't have power-off handler installed at all. All platforms that I tested have a power-off handler, so now wonder that I didn't notice this before.
>>
>> This change should fix the problem, please give it a try:
>
> Thank you, that fixes the problem for me!
>
> Tested-by: Geert Uytterhoeven <geert+renesas@...der.be>
Great! I'll send the proper patch soon.
--
Best regards,
Dmitry
Powered by blists - more mailing lists