Bug: Re: [PATCH v3] ACPI: Split out processor thermal register from ACPI PSS

[Jeremy Linton]

Hi,

On 6/16/22 21:51, Riwen Lu wrote:
> From: Riwen Lu <luriwen@xxxxxxxxxx>
>
> Commit 239708a3af44 ("ACPI: Split out ACPI PSS from ACPI Processor
> driver"), moves processor thermal registration to acpi_pss_perf_init(),
> which doesn't get executed if ACPI_CPU_FREQ_PSS is not enabled.
>
> As ARM64 supports P-states using CPPC, it should be possible to also
> support processor passive cooling even if PSS is not enabled. Split
> out the processor thermal cooling register from ACPI PSS to support
> this, and move it into a separate function in processor_thermal.c.

It appears this commit 7fdc74da940d ACPI: processor: Split out thermal 
initialization from ACPI PSS

Is causing the following:
   41.341659] ------------[ cut here ]------------
[   41.346280] freq_qos_remove_request() called for unknown object
[   41.352251] WARNING: CPU: 3 PID: 1089 at kernel/power/qos.c:597 
freq_qos_remove_request+0xa4/0xc4
[   41.361152] Modules linked in: nf_nat_tftp nft_objref 
nf_conntrack_tftp nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib 
nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct 
nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set 
nf_tables nfnetlink qrtr bnep sunrpc vfat fat btsdio brcmfmac hci_uart 
btqca cfg80211 bs
[   41.413245] CPU: 3 PID: 1089 Comm: rmmod Not tainted 6.0.0-rc1MINI+ #237
[   41.419951] Hardware name: Raspberry Pi Foundation Raspberry Pi 4 
Model B/Raspberry Pi 4 Model B, BIOS EDK2-DEV 07/18/2022
[   41.430990] pstate: 40400005 (nZcv daif +PAN -UAO -TCO -DIT -SSBS 
BTYPE=--)
[   41.437955] pc : freq_qos_remove_request+0xa4/0xc4
[   41.442752] lr : freq_qos_remove_request+0xa4/0xc4
[   41.447550] sp : ffff80000a4bbb60
[   41.450862] x29: ffff80000a4bbb60 x28: ffff07858798a1c0 x27: 
0000000000000000
[   41.458012] x26: 0000000000000000 x25: ffffdf6ade80f850 x24: 
ffff07858b07d200
[   41.465158] x23: ffffdf6ade812cb0 x22: ffff07858b07d000 x21: 
ffffdf6ade80f850
[   41.472303] x20: ffffdf6ade26b998 x19: ffff0785809ba5a8 x18: 
ffffffffffffffff
[   41.479447] x17: 0000000000000000 x16: ffffdf6adcc25320 x15: 
0000000000000006
[   41.486592] x14: 0000000000000000 x13: 7463656a626f206e x12: 
776f6e6b6e752072
[   41.493736] x11: 00000000ffffdfff x10: ffffdf6ade8fd520 x9 : 
ffffdf6adcae53ac
[   41.500881] x8 : 000000000002ffe8 x7 : c0000000ffffdfff x6 : 
0000000000000001
[   41.508026] x5 : 0000000000000000 x4 : ffff07863b7ac450 x3 : 
ffff07863b7b8bb0
[   41.515170] x2 : 0000000000000001 x1 : ffff281b5d54f000 x0 : 
0000000000000033
[   41.522315] Call trace:
[   41.524759]  freq_qos_remove_request+0xa4/0xc4
[   41.529210]  acpi_thermal_cpufreq_exit+0x90/0xb0
[   41.533834]  acpi_processor_notifier+0x74/0x90
[   41.538281]  blocking_notifier_call_chain+0x78/0xb0
[   41.543161]  cpufreq_policy_free+0x154/0x1e0
[   41.547438]  cpufreq_remove_dev+0xc0/0x10c
[   41.551538]  subsys_interface_unregister+0xf0/0xfc
[   41.556335]  cpufreq_unregister_driver+0x54/0x120
[   41.561043]  cppc_cpufreq_exit+0x28/0xd2c [cppc_cpufreq]
[   41.566370]  __do_sys_delete_module.constprop.0+0x150/0x2bc
[   41.571947]  __arm64_sys_delete_module+0x20/0x30
[   41.576567]  invoke_syscall+0x50/0x120
[   41.580318]  el0_svc_common.constprop.0+0x4c/0xf4
[   41.585023]  do_el0_svc+0x38/0x4c
[   41.588338]  el0_svc+0x34/0xdc
[   41.591394]  el0t_64_sync_handler+0x11c/0x150
[   41.595752]  el0t_64_sync+0x190/0x194
[   41.599416] ---[ end trace 0000000000000000 ]---

When the cppc_cpufreq driver is rmmod'ed from a running machine that has 
both CPPC and a thermal zone. I reverted and bisected it, and in both 
cases the splat above goes away.


Thanks,

> Signed-off-by: Riwen Lu <luriwen@xxxxxxxxxx>
>
> ---
> v1 -> v2:
>   - Reword the commit message.
>   - Update the signature of acpi_pss_perf_init() to void, and remove the
>     acpi_device parameter.
>   - Move the processor thermal register/remove into a separate function in
>     processor_thermal.c.
>
> v2 -> v3:
>   - Remove the "pr" NULL check in processor thermal init/exit fuction.
>   - Pass the acpi_device into processor thermal init/exit, and remove the
>     convert in it.
> ---
>   drivers/acpi/Kconfig             |  2 +-
>   drivers/acpi/Makefile            |  5 +--
>   drivers/acpi/processor_driver.c  | 72 ++++----------------------------
>   drivers/acpi/processor_thermal.c | 54 ++++++++++++++++++++++++
>   include/acpi/processor.h         |  8 +++-
>   5 files changed, 71 insertions(+), 70 deletions(-)
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 1e34f846508f..2457ade3f82d 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -255,7 +255,6 @@ config ACPI_DOCK
>   
>   config ACPI_CPU_FREQ_PSS
>   	bool
> -	select THERMAL
>   
>   config ACPI_PROCESSOR_CSTATE
>   	def_bool y
> @@ -287,6 +286,7 @@ config ACPI_PROCESSOR
>   	depends on X86 || IA64 || ARM64 || LOONGARCH
>   	select ACPI_PROCESSOR_IDLE
>   	select ACPI_CPU_FREQ_PSS if X86 || IA64 || LOONGARCH
> +	select THERMAL
>   	default y
>   	help
>   	  This driver adds support for the ACPI Processor package. It is required
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index b5a8d3e00a52..0002eecbf870 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -109,10 +109,9 @@ obj-$(CONFIG_ACPI_PPTT) 	+= pptt.o
>   obj-$(CONFIG_ACPI_PFRUT)	+= pfr_update.o pfr_telemetry.o
>   
>   # processor has its own "processor." module_param namespace
> -processor-y			:= processor_driver.o
> +processor-y			:= processor_driver.o processor_thermal.o
>   processor-$(CONFIG_ACPI_PROCESSOR_IDLE) += processor_idle.o
> -processor-$(CONFIG_ACPI_CPU_FREQ_PSS)	+= processor_throttling.o	\
> -	processor_thermal.o
> +processor-$(CONFIG_ACPI_CPU_FREQ_PSS)	+= processor_throttling.o
>   processor-$(CONFIG_CPU_FREQ)	+= processor_perflib.o
>   
>   obj-$(CONFIG_ACPI_PROCESSOR_AGGREGATOR) += acpi_pad.o
> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> index 368a9edefd0c..1278969eec1f 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -139,75 +139,17 @@ static int acpi_soft_cpu_dead(unsigned int cpu)
>   }
>   
>   #ifdef CONFIG_ACPI_CPU_FREQ_PSS
> -static int acpi_pss_perf_init(struct acpi_processor *pr,
> -		struct acpi_device *device)
> +static void acpi_pss_perf_init(struct acpi_processor *pr)
>   {
> -	int result = 0;
> -
>   	acpi_processor_ppc_has_changed(pr, 0);
>   
>   	acpi_processor_get_throttling_info(pr);
>   
>   	if (pr->flags.throttling)
>   		pr->flags.limit = 1;
> -
> -	pr->cdev = thermal_cooling_device_register("Processor", device,
> -						   &processor_cooling_ops);
> -	if (IS_ERR(pr->cdev)) {
> -		result = PTR_ERR(pr->cdev);
> -		return result;
> -	}
> -
> -	dev_dbg(&device->dev, "registered as cooling_device%d\n",
> -		pr->cdev->id);
> -
> -	result = sysfs_create_link(&device->dev.kobj,
> -				   &pr->cdev->device.kobj,
> -				   "thermal_cooling");
> -	if (result) {
> -		dev_err(&device->dev,
> -			"Failed to create sysfs link 'thermal_cooling'\n");
> -		goto err_thermal_unregister;
> -	}
> -
> -	result = sysfs_create_link(&pr->cdev->device.kobj,
> -				   &device->dev.kobj,
> -				   "device");
> -	if (result) {
> -		dev_err(&pr->cdev->device,
> -			"Failed to create sysfs link 'device'\n");
> -		goto err_remove_sysfs_thermal;
> -	}
> -
> -	return 0;
> -
> - err_remove_sysfs_thermal:
> -	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
> - err_thermal_unregister:
> -	thermal_cooling_device_unregister(pr->cdev);
> -
> -	return result;
> -}
> -
> -static void acpi_pss_perf_exit(struct acpi_processor *pr,
> -		struct acpi_device *device)
> -{
> -	if (pr->cdev) {
> -		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
> -		sysfs_remove_link(&pr->cdev->device.kobj, "device");
> -		thermal_cooling_device_unregister(pr->cdev);
> -		pr->cdev = NULL;
> -	}
>   }
>   #else
> -static inline int acpi_pss_perf_init(struct acpi_processor *pr,
> -		struct acpi_device *device)
> -{
> -	return 0;
> -}
> -
> -static inline void acpi_pss_perf_exit(struct acpi_processor *pr,
> -		struct acpi_device *device) {}
> +static inline void acpi_pss_perf_init(struct acpi_processor *pr) {}
>   #endif /* CONFIG_ACPI_CPU_FREQ_PSS */
>   
>   static int __acpi_processor_start(struct acpi_device *device)
> @@ -229,7 +171,9 @@ static int __acpi_processor_start(struct acpi_device *device)
>   	if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
>   		acpi_processor_power_init(pr);
>   
> -	result = acpi_pss_perf_init(pr, device);
> +	acpi_pss_perf_init(pr);
> +
> +	result = acpi_processor_thermal_init(pr, device);
>   	if (result)
>   		goto err_power_exit;
>   
> @@ -239,7 +183,7 @@ static int __acpi_processor_start(struct acpi_device *device)
>   		return 0;
>   
>   	result = -ENODEV;
> -	acpi_pss_perf_exit(pr, device);
> +	acpi_processor_thermal_exit(pr, device);
>   
>   err_power_exit:
>   	acpi_processor_power_exit(pr);
> @@ -277,10 +221,10 @@ static int acpi_processor_stop(struct device *dev)
>   		return 0;
>   	acpi_processor_power_exit(pr);
>   
> -	acpi_pss_perf_exit(pr, device);
> -
>   	acpi_cppc_processor_exit(pr);
>   
> +	acpi_processor_thermal_exit(pr, device);
> +
>   	return 0;
>   }
>   
> diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
> index d8b2dfcd59b5..db6ac540e924 100644
> --- a/drivers/acpi/processor_thermal.c
> +++ b/drivers/acpi/processor_thermal.c
> @@ -266,3 +266,57 @@ const struct thermal_cooling_device_ops processor_cooling_ops = {
>   	.get_cur_state = processor_get_cur_state,
>   	.set_cur_state = processor_set_cur_state,
>   };
> +
> +int acpi_processor_thermal_init(struct acpi_processor *pr,
> +				struct acpi_device *device)
> +{
> +	int result = 0;
> +
> +	pr->cdev = thermal_cooling_device_register("Processor", device,
> +						   &processor_cooling_ops);
> +	if (IS_ERR(pr->cdev)) {
> +		result = PTR_ERR(pr->cdev);
> +		return result;
> +	}
> +
> +	dev_dbg(&device->dev, "registered as cooling_device%d\n",
> +		pr->cdev->id);
> +
> +	result = sysfs_create_link(&device->dev.kobj,
> +				   &pr->cdev->device.kobj,
> +				   "thermal_cooling");
> +	if (result) {
> +		dev_err(&device->dev,
> +			"Failed to create sysfs link 'thermal_cooling'\n");
> +		goto err_thermal_unregister;
> +	}
> +
> +	result = sysfs_create_link(&pr->cdev->device.kobj,
> +				   &device->dev.kobj,
> +				   "device");
> +	if (result) {
> +		dev_err(&pr->cdev->device,
> +			"Failed to create sysfs link 'device'\n");
> +		goto err_remove_sysfs_thermal;
> +	}
> +
> +	return 0;
> +
> +err_remove_sysfs_thermal:
> +	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
> +err_thermal_unregister:
> +	thermal_cooling_device_unregister(pr->cdev);
> +
> +	return result;
> +}
> +
> +void acpi_processor_thermal_exit(struct acpi_processor *pr,
> +				 struct acpi_device *device)
> +{
> +	if (pr->cdev) {
> +		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
> +		sysfs_remove_link(&pr->cdev->device.kobj, "device");
> +		thermal_cooling_device_unregister(pr->cdev);
> +		pr->cdev = NULL;
> +	}
> +}
> diff --git a/include/acpi/processor.h b/include/acpi/processor.h
> index 194027371928..ba1e3ed98d3d 100644
> --- a/include/acpi/processor.h
> +++ b/include/acpi/processor.h
> @@ -442,8 +442,12 @@ static inline int acpi_processor_hotplug(struct acpi_processor *pr)
>   
>   /* in processor_thermal.c */
>   int acpi_processor_get_limit_info(struct acpi_processor *pr);
> +int acpi_processor_thermal_init(struct acpi_processor *pr,
> +				struct acpi_device *device);
> +void acpi_processor_thermal_exit(struct acpi_processor *pr,
> +				 struct acpi_device *device);
>   extern const struct thermal_cooling_device_ops processor_cooling_ops;
> -#if defined(CONFIG_ACPI_CPU_FREQ_PSS) & defined(CONFIG_CPU_FREQ)
> +#ifdef CONFIG_CPU_FREQ
>   void acpi_thermal_cpufreq_init(struct cpufreq_policy *policy);
>   void acpi_thermal_cpufreq_exit(struct cpufreq_policy *policy);
>   #else
> @@ -455,6 +459,6 @@ static inline void acpi_thermal_cpufreq_exit(struct cpufreq_policy *policy)
>   {
>   	return;
>   }
> -#endif	/* CONFIG_ACPI_CPU_FREQ_PSS */
> +#endif	/* CONFIG_CPU_FREQ */
>   
>   #endif