From: Masayoshi Mizuma <[email protected]>
When a physical cpu is hot-removed, the following warning message
are shown while the uncore device is removing in uncore_pci_remove().
WARNING: CPU: 120 PID: 5 at arch/x86/events/intel/uncore.c:988
uncore_pci_remove+0xf1/0x110
...
CPU: 120 PID: 5 Comm: kworker/u1024:0 Not tainted 4.15.0-rc8 #1
Workqueue: kacpi_hotplug acpi_hotplug_work_fn
...
Call Trace:
pci_device_remove+0x36/0xb0
device_release_driver_internal+0x145/0x210
pci_stop_bus_device+0x76/0xa0
pci_stop_root_bus+0x44/0x60
acpi_pci_root_remove+0x1f/0x80
acpi_bus_trim+0x54/0x90
acpi_bus_trim+0x2e/0x90
acpi_device_hotplug+0x2bc/0x4b0
acpi_hotplug_work_fn+0x1a/0x30
process_one_work+0x141/0x340
worker_thread+0x47/0x3e0
kthread+0xf5/0x130
When uncore_pci_remove() runs, it tries to get package id to
clear the value of uncore_extra_pci_dev[].dev[] by using
topology_phys_to_logical_pkg(). The warning messesage are
shown because topology_phys_to_logical_pkg() returns -1.
arch/x86/events/intel/uncore.c:
static void uncore_pci_remove(struct pci_dev *pdev)
{
...
phys_id = uncore_pcibus_to_physid(pdev->bus);
...
pkg = topology_phys_to_logical_pkg(phys_id); //returns -1
for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {
if (uncore_extra_pci_dev[pkg].dev[i] == pdev) {
uncore_extra_pci_dev[pkg].dev[i] = NULL;
break;
}
}
WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX); //HERE!!
topology_phys_to_logical_pkg() tries to find
cpuinfo_x86->phys_proc_id that matches the phys_pkg argument.
arch/x86/kernel/smpboot.c:
int topology_phys_to_logical_pkg(unsigned int phys_pkg)
{
int cpu;
for_each_possible_cpu(cpu) {
struct cpuinfo_x86 *c = &cpu_data(cpu);
if (c->initialized && c->phys_proc_id == phys_pkg)
return c->logical_proc_id;
}
return -1;
}
However, the phys_proc_id is already set to 0 by remove_siblinginfo()
when the cpu was offlined.
So, topology_phys_to_logical_pkg() cannot find correct the
logical_proc_id and always returns -1.
As the result, uncore_pci_remove() calls WARN_ON_ONCE() and the warning
messages are shown.
To avoid this, remove the setting from remove_siblinginfo().
There is no influence about the removing because phys_proc_id is not
used after it is hot-removed and it is re-set while hot-addeding.
Signed-off-by: Masayoshi Mizuma <[email protected]>
---
arch/x86/kernel/smpboot.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ed556d5..844279c 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1431,7 +1431,6 @@ static void remove_siblinginfo(int cpu)
cpumask_clear(cpu_llc_shared_mask(cpu));
cpumask_clear(topology_sibling_cpumask(cpu));
cpumask_clear(topology_core_cpumask(cpu));
- c->phys_proc_id = 0;
c->cpu_core_id = 0;
cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
recompute_smt_state();
--
1.8.3.1
- Masayoshi
CC:+Andi Kleen
Hi Masayoshi,
This issue is caused by the following commit:
commit 30bb9811856f667042e746d8033883b1091a46ce
Author: Andi Kleen <[email protected]>
Date: Tue Nov 14 07:42:56 2017 -0500
x86/topology: Avoid wasting 128k for package id array
So you should add the following "Fixes:" tag in the description.
Fixes: 30bb9811856f ("x86/topology: Avoid wasting 128k for package id array")
Thanks,
Yasuaki Ishimatsu
On 02/05/2018 10:51 PM, Masayoshi Mizuma wrote:
> From: Masayoshi Mizuma <[email protected]>
>
> When a physical cpu is hot-removed, the following warning message
> are shown while the uncore device is removing in uncore_pci_remove().
>
> WARNING: CPU: 120 PID: 5 at arch/x86/events/intel/uncore.c:988
> uncore_pci_remove+0xf1/0x110
> ...
> CPU: 120 PID: 5 Comm: kworker/u1024:0 Not tainted 4.15.0-rc8 #1
> Workqueue: kacpi_hotplug acpi_hotplug_work_fn
> ...
> Call Trace:
> pci_device_remove+0x36/0xb0
> device_release_driver_internal+0x145/0x210
> pci_stop_bus_device+0x76/0xa0
> pci_stop_root_bus+0x44/0x60
> acpi_pci_root_remove+0x1f/0x80
> acpi_bus_trim+0x54/0x90
> acpi_bus_trim+0x2e/0x90
> acpi_device_hotplug+0x2bc/0x4b0
> acpi_hotplug_work_fn+0x1a/0x30
> process_one_work+0x141/0x340
> worker_thread+0x47/0x3e0
> kthread+0xf5/0x130
>
> When uncore_pci_remove() runs, it tries to get package id to
> clear the value of uncore_extra_pci_dev[].dev[] by using
> topology_phys_to_logical_pkg(). The warning messesage are
> shown because topology_phys_to_logical_pkg() returns -1.
>
> arch/x86/events/intel/uncore.c:
> static void uncore_pci_remove(struct pci_dev *pdev)
> {
> ...
> phys_id = uncore_pcibus_to_physid(pdev->bus);
> ...
> pkg = topology_phys_to_logical_pkg(phys_id); //returns -1
> for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {
> if (uncore_extra_pci_dev[pkg].dev[i] == pdev) {
> uncore_extra_pci_dev[pkg].dev[i] = NULL;
> break;
> }
> }
> WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX); //HERE!!
>
> topology_phys_to_logical_pkg() tries to find
> cpuinfo_x86->phys_proc_id that matches the phys_pkg argument.
>
> arch/x86/kernel/smpboot.c:
> int topology_phys_to_logical_pkg(unsigned int phys_pkg)
> {
> int cpu;
>
> for_each_possible_cpu(cpu) {
> struct cpuinfo_x86 *c = &cpu_data(cpu);
>
> if (c->initialized && c->phys_proc_id == phys_pkg)
> return c->logical_proc_id;
> }
> return -1;
> }
>
> However, the phys_proc_id is already set to 0 by remove_siblinginfo()
> when the cpu was offlined.
> So, topology_phys_to_logical_pkg() cannot find correct the
> logical_proc_id and always returns -1.
> As the result, uncore_pci_remove() calls WARN_ON_ONCE() and the warning
> messages are shown.
>
> To avoid this, remove the setting from remove_siblinginfo().
> There is no influence about the removing because phys_proc_id is not
> used after it is hot-removed and it is re-set while hot-addeding.
>
> Signed-off-by: Masayoshi Mizuma <[email protected]>
>
> ---
> arch/x86/kernel/smpboot.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
> index ed556d5..844279c 100644
> --- a/arch/x86/kernel/smpboot.c
> +++ b/arch/x86/kernel/smpboot.c
> @@ -1431,7 +1431,6 @@ static void remove_siblinginfo(int cpu)
> cpumask_clear(cpu_llc_shared_mask(cpu));
> cpumask_clear(topology_sibling_cpumask(cpu));
> cpumask_clear(topology_core_cpumask(cpu));
> - c->phys_proc_id = 0;
> c->cpu_core_id = 0;
> cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
> recompute_smt_state();
>
Hello Yasuaki,
Thank you for your comment.
I will add the Fixes tag and resend the patch.
- Masayoshi
Wed, 7 Feb 2018 19:24:26 +0900 Yasuaki Ishimatsu wrote:
> CC:+Andi Kleen
>
> Hi Masayoshi,
>
> This issue is caused by the following commit:
>
> commit 30bb9811856f667042e746d8033883b1091a46ce
> Author: Andi Kleen <[email protected]>
> Date: Tue Nov 14 07:42:56 2017 -0500
>
> x86/topology: Avoid wasting 128k for package id array
>
> So you should add the following "Fixes:" tag in the description.
>
> Fixes: 30bb9811856f ("x86/topology: Avoid wasting 128k for package id array")
>
> Thanks,
> Yasuaki Ishimatsu
>
> On 02/05/2018 10:51 PM, Masayoshi Mizuma wrote:
>> From: Masayoshi Mizuma <[email protected]>
>>
>> When a physical cpu is hot-removed, the following warning message
>> are shown while the uncore device is removing in uncore_pci_remove().
>>
>> WARNING: CPU: 120 PID: 5 at arch/x86/events/intel/uncore.c:988
>> uncore_pci_remove+0xf1/0x110
>> ...
>> CPU: 120 PID: 5 Comm: kworker/u1024:0 Not tainted 4.15.0-rc8 #1
>> Workqueue: kacpi_hotplug acpi_hotplug_work_fn
>> ...
>> Call Trace:
>> pci_device_remove+0x36/0xb0
>> device_release_driver_internal+0x145/0x210
>> pci_stop_bus_device+0x76/0xa0
>> pci_stop_root_bus+0x44/0x60
>> acpi_pci_root_remove+0x1f/0x80
>> acpi_bus_trim+0x54/0x90
>> acpi_bus_trim+0x2e/0x90
>> acpi_device_hotplug+0x2bc/0x4b0
>> acpi_hotplug_work_fn+0x1a/0x30
>> process_one_work+0x141/0x340
>> worker_thread+0x47/0x3e0
>> kthread+0xf5/0x130
>>
>> When uncore_pci_remove() runs, it tries to get package id to
>> clear the value of uncore_extra_pci_dev[].dev[] by using
>> topology_phys_to_logical_pkg(). The warning messesage are
>> shown because topology_phys_to_logical_pkg() returns -1.
>>
>> arch/x86/events/intel/uncore.c:
>> static void uncore_pci_remove(struct pci_dev *pdev)
>> {
>> ...
>> phys_id = uncore_pcibus_to_physid(pdev->bus);
>> ...
>> pkg = topology_phys_to_logical_pkg(phys_id); //returns -1
>> for (i = 0; i < UNCORE_EXTRA_PCI_DEV_MAX; i++) {
>> if (uncore_extra_pci_dev[pkg].dev[i] == pdev) {
>> uncore_extra_pci_dev[pkg].dev[i] = NULL;
>> break;
>> }
>> }
>> WARN_ON_ONCE(i >= UNCORE_EXTRA_PCI_DEV_MAX); //HERE!!
>>
>> topology_phys_to_logical_pkg() tries to find
>> cpuinfo_x86->phys_proc_id that matches the phys_pkg argument.
>>
>> arch/x86/kernel/smpboot.c:
>> int topology_phys_to_logical_pkg(unsigned int phys_pkg)
>> {
>> int cpu;
>>
>> for_each_possible_cpu(cpu) {
>> struct cpuinfo_x86 *c = &cpu_data(cpu);
>>
>> if (c->initialized && c->phys_proc_id == phys_pkg)
>> return c->logical_proc_id;
>> }
>> return -1;
>> }
>>
>> However, the phys_proc_id is already set to 0 by remove_siblinginfo()
>> when the cpu was offlined.
>> So, topology_phys_to_logical_pkg() cannot find correct the
>> logical_proc_id and always returns -1.
>> As the result, uncore_pci_remove() calls WARN_ON_ONCE() and the warning
>> messages are shown.
>>
>> To avoid this, remove the setting from remove_siblinginfo().
>> There is no influence about the removing because phys_proc_id is not
>> used after it is hot-removed and it is re-set while hot-addeding.
>>
>> Signed-off-by: Masayoshi Mizuma <[email protected]>
>>
>> ---
>> arch/x86/kernel/smpboot.c | 1 -
>> 1 file changed, 1 deletion(-)
>>
>> diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
>> index ed556d5..844279c 100644
>> --- a/arch/x86/kernel/smpboot.c
>> +++ b/arch/x86/kernel/smpboot.c
>> @@ -1431,7 +1431,6 @@ static void remove_siblinginfo(int cpu)
>> cpumask_clear(cpu_llc_shared_mask(cpu));
>> cpumask_clear(topology_sibling_cpumask(cpu));
>> cpumask_clear(topology_core_cpumask(cpu));
>> - c->phys_proc_id = 0;
>> c->cpu_core_id = 0;
>> cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
>> recompute_smt_state();
>>