Re: [PATCH v6 00/25] PM / Domains: Support hierarchical CPU arrangement (PSCI/ARM)

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Ulf,

On Wed, Mar 14, 2018 at 5:58 PM, Ulf Hansson <ulf.hansson@linaro.org> wrote:
> This series is a re-worked version from Lina Iyer's two series [1] that got
> posted more than a year ago by now. I have picked up the series and done a
> significant re-work of it and here's the result. All patches have been changed,
> some have been dropped, some are entirely new. For this reason I decided to not
> include a version history, as I think people need a fresh start anyway.

Thanks for your series!

I gave it a try on a few Renesas boards and SoCs, without adding any new DT
descriptions.  On all of them it triggers

    BUG: sleeping function called from invalid context at
drivers/base/power/runtime.c:1057

during system suspend (s2ram).

On R-Car Gen2 and SH-Mobile AG5 (arm32, no PSCI):

Disabling non-boot CPUs ...
BUG: sleeping function called from invalid context at
drivers/base/power/runtime.c:1057
in_atomic(): 0, irqs_disabled(): 128, pid: 1725, name: s2ram
CPU: 0 PID: 1725 Comm: s2ram Not tainted
4.16.0-rc5-koelsch-00475-gaa69fc46cc44c3d7 #4001
Hardware name: Generic R-Car Gen2 (Flattened Device Tree)
[<c020f6a0>] (unwind_backtrace) from [<c020b324>] (show_stack+0x10/0x14)
[<c020b324>] (show_stack) from [<c07693c8>] (dump_stack+0x7c/0x9c)
[<c07693c8>] (dump_stack) from [<c02422ec>] (___might_sleep+0x128/0x164)
[<c02422ec>] (___might_sleep) from [<c0508efc>] (__pm_runtime_suspend+0x70/0xa8)
[<c0508efc>] (__pm_runtime_suspend) from [<c0299144>] (cpu_pm_enter+0x78/0x9c)
[<c0299144>] (cpu_pm_enter) from [<c0299170>] (cpu_pm_suspend+0x8/0x18)
[<c0299170>] (cpu_pm_suspend) from [<c04ff8c4>] (syscore_suspend+0x88/0x138)
[<c04ff8c4>] (syscore_suspend) from [<c0263010>]
(suspend_devices_and_enter+0x21c/0x564)
[<c0263010>] (suspend_devices_and_enter) from [<c02635a8>]
(pm_suspend+0x250/0x2c8)
[<c02635a8>] (pm_suspend) from [<c0262054>] (state_store+0xac/0xcc)
[<c0262054>] (state_store) from [<c035f238>] (kernfs_fop_write+0x170/0x1b0)
[<c035f238>] (kernfs_fop_write) from [<c02f8a5c>] (__vfs_write+0x2c/0x140)
[<c02f8a5c>] (__vfs_write) from [<c02f8ce4>] (vfs_write+0xb8/0x144)
[<c02f8ce4>] (vfs_write) from [<c02f8ea4>] (SyS_write+0x54/0xac)
[<c02f8ea4>] (SyS_write) from [<c0201000>] (ret_fast_syscall+0x0/0x4c)
Exception stack(0xeabcbfa8 to 0xeabcbff0)
bfa0:                   00000004 000ce408 00000001 000ce408 00000004 00000000
bfc0: 00000004 000ce408 b6e80b50 00000004 00000004 00000000 000c5758 00000000
bfe0: 00000000 be866754 b6de3c85 b6e1ef26


On R-Car Gen3 (arm64, PSCI):

Disabling non-boot CPUs ...
CPU1: shutdown
psci: CPU1 killed.
CPU2: shutdown
psci: CPU2 killed.
CPU3: shutdown
psci: CPU3 killed.
CPU4: shutdown
psci: CPU4 killed.
CPU5: shutdown
psci: CPU5 killed.
CPU6: shutdown
psci: CPU6 killed.
CPU7: shutdown
psci: CPU7 killed.
BUG: sleeping function called from invalid context at
drivers/base/power/runtime.c:1057
in_atomic(): 0, irqs_disabled(): 128, pid: 2592, name: s2ram
4 locks held by s2ram/2592:
 #0:  (sb_writers#7){.+.+}, at: [<00000000cae1f0e5>] vfs_write+0xb0/0x164
 #1:  (&of->mutex){+.+.}, at: [<000000003002e527>] kernfs_fop_write+0x114/0x1bc
 #2:  (kn->count#71){.+.+}, at: [<000000008c0217e1>]
kernfs_fop_write+0x11c/0x1bc
 #3:  (pm_mutex){+.+.}, at: [<000000009a6c23e2>] pm_suspend+0x194/0xb10
irq event stamp: 69308
hardirqs last  enabled at (69307): [<00000000e9d09767>]
_raw_spin_unlock_irq+0x2c/0x4c
hardirqs last disabled at (69308): [<00000000619169c4>]
arch_suspend_disable_irqs+0x10/0x18
softirqs last  enabled at (69246): [<00000000b8a7706e>]
hrtimers_dead_cpu+0x2b8/0x2f0
softirqs last disabled at (69242): [<000000004dee0c40>]
hrtimers_dead_cpu+0x48/0x2f0
CPU: 0 PID: 2592 Comm: s2ram Not tainted
4.16.0-rc5-salvator-x-00470-g319cfb3643965f46 #1685
Hardware name: Renesas Salvator-X 2nd version board based on r8a7795 ES2.0+ (DT)
Call trace:
 dump_backtrace+0x0/0x140
 show_stack+0x14/0x1c
 dump_stack+0xb4/0xf0
 ___might_sleep+0x1fc/0x218
 __might_sleep+0x70/0x80
 __pm_runtime_suspend+0x6c/0xac
 cpu_pm_enter+0x74/0x9c
 cpu_pm_suspend+0xc/0x1c
 syscore_suspend+0x1b8/0x410
 suspend_devices_and_enter+0x210/0xd9c
 pm_suspend+0x9a4/0xb10
 state_store+0xd4/0xf8
 kobj_attr_store+0x18/0x28
 sysfs_kf_write+0x50/0x5c
 kernfs_fop_write+0x178/0x1bc
 __vfs_write+0x38/0x140
 vfs_write+0xc4/0x164
 SyS_write+0x54/0xa4
 el0_svc_naked+0x30/0x34


I've bisected this to "[PATCH v6 09/25] kernel/cpu_pm: Manage runtime PM
in the idle path for CPUs".

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds