Re: [PATCH v3 1/5] misc: pci_endpoint_test: Avoid issue of interrupts remaining after request_irq error

[Kunihiko Hayashi <hayashi.kunihiko@socionext.com>]

Hi Manivannan,

On 2025/02/15 2:21, Manivannan Sadhasivam wrote:
> On Mon, Feb 10, 2025 at 04:58:08PM +0900, Kunihiko Hayashi wrote:
>> After devm_request_irq() fails with error in
>> pci_endpoint_test_request_irq(), pci_endpoint_test_free_irq_vectors() is
>> called assuming that all IRQs have been released.
>>
>> However some requested IRQs remain unreleased, so there are still
>> /proc/irq/* entries remaining and we encounters WARN() with the following
> 
> s/we encounters/this results in WARN()

I see. I'll fix it.

>> message:
>>
>>      remove_proc_entry: removing non-empty directory 'irq/30', leaking at
>>      least 'pci-endpoint-test.0'
>>      WARNING: CPU: 0 PID: 202 at fs/proc/generic.c:719 remove_proc_entry
>>      +0x190/0x19c
>>
>> And show the call trace that led to this issue:
> 
> You can remove this backtrace.

I'll add more information instead.

> 
>>
>>      [   12.050005] Call trace:
>>      [   12.051226]  remove_proc_entry+0x190/0x19c (P)
>>      [   12.053448]  unregister_irq_proc+0xd0/0x104
>>      [   12.055541]  free_desc+0x4c/0xd0
>>      [   12.057155]  irq_free_descs+0x68/0x90
>>      [   12.058984]  irq_domain_free_irqs+0x15c/0x1bc
>>      [   12.061161]  msi_domain_free_locked.part.0+0x184/0x1d4
>>      [   12.063728]  msi_domain_free_irqs_all_locked+0x64/0x8c
>>      [   12.066296]  pci_msi_teardown_msi_irqs+0x48/0x54
>>      [   12.068604]  pci_free_msi_irqs+0x18/0x38
>>      [   12.070564]  pci_free_irq_vectors+0x64/0x8c
>>      [   12.072654]  pci_endpoint_test_ioctl+0x870/0x1068
>>      [   12.075006]  __arm64_sys_ioctl+0xb0/0xe8
>>      [   12.076967]  invoke_syscall+0x48/0x110
>>      [   12.078841]  el0_svc_common.constprop.0+0x40/0xe8
>>      [   12.081192]  do_el0_svc+0x20/0x2c
>>      [   12.082848]  el0_svc+0x30/0xd0
>>      [   12.084376]  el0t_64_sync_handler+0x144/0x168
>>      [   12.086553]  el0t_64_sync+0x198/0x19c
>>      [   12.088383] ---[ end trace 0000000000000000 ]---
>>
>> To solve this issue, set the number of remaining IRQs to test->num_irqs
>> and release IRQs in advance by calling pci_endpoint_test_release_irq().
>>
>> Cc: stable@vger.kernel.org
>> Fixes: e03327122e2c ("pci_endpoint_test: Add 2 ioctl commands")
>> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> 
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thank you,

---
Best Regards
Kunihiko Hayashi