| Message ID | 20240220111019.133697-1-herve.codina@bootlin.com |
|---|---|
| Headers | show |
| Series | gpio-cdev: Release IRQ used by gpio-cdev on gpio chip removal | expand |
On Tue, Feb 20, 2024 at 12:10 PM Herve Codina <herve.codina@bootlin.com> wrote: > > Hi, > > When a gpio chip device is removed while some related gpio are used by > the user-space (gpiomon for instance), the following warning can appear: > remove_proc_entry: removing non-empty directory 'irq/233', leaking at least 'gpiomon' > WARNING: CPU: 2 PID: 72 at fs/proc/generic.c:717 remove_proc_entry+0x190/0x19c > ... > Call trace: > remove_proc_entry+0x190/0x19c > unregister_irq_proc+0xd0/0x104 > free_desc+0x4c/0xc4 > irq_free_descs+0x6c/0x90 > irq_dispose_mapping+0x104/0x14c > gpiochip_irqchip_remove+0xcc/0x1a4 > gpiochip_remove+0x48/0x100 > ... > > Indeed, even if the gpio removal is notified to the gpio-cdev, the > IRQ used is not released when it should be. > > This series calls the gpio removal notifier sooner in the removal > process in order to give a chance to a notifier function to release > the IRQ before releasing the IRQ mapping and adds the needed > operations to release the IRQ in the gpio cdev notifier function. > > Best regards, > Hervé Codina > > Herve Codina (2): > gpiolib: call gcdev_unregister() sooner in the removal operations > gpiolib: cdev: release IRQs when the gpio chip device is removed > > drivers/gpio/gpiolib-cdev.c | 33 ++++++++++++++++++++++----------- > drivers/gpio/gpiolib.c | 8 +++++++- > 2 files changed, 29 insertions(+), 12 deletions(-) > > -- > 2.43.0 > Thanks for taking a stab at it. I saw this issue some time ago, tried to fix it directly in interrupt procfs code[1], got yelled at by Thomas Gleixner for 20 or so emails and eventually forgot about it. Nice to see someone tackle it again. Bart [1] https://lore.kernel.org/lkml/20230814093621.23209-1-brgl@bgdev.pl/
Hi, When a gpio chip device is removed while some related gpio are used by the user-space (gpiomon for instance), the following warning can appear: remove_proc_entry: removing non-empty directory 'irq/233', leaking at least 'gpiomon' WARNING: CPU: 2 PID: 72 at fs/proc/generic.c:717 remove_proc_entry+0x190/0x19c ... Call trace: remove_proc_entry+0x190/0x19c unregister_irq_proc+0xd0/0x104 free_desc+0x4c/0xc4 irq_free_descs+0x6c/0x90 irq_dispose_mapping+0x104/0x14c gpiochip_irqchip_remove+0xcc/0x1a4 gpiochip_remove+0x48/0x100 ... Indeed, even if the gpio removal is notified to the gpio-cdev, the IRQ used is not released when it should be. This series calls the gpio removal notifier sooner in the removal process in order to give a chance to a notifier function to release the IRQ before releasing the IRQ mapping and adds the needed operations to release the IRQ in the gpio cdev notifier function. Best regards, Hervé Codina Herve Codina (2): gpiolib: call gcdev_unregister() sooner in the removal operations gpiolib: cdev: release IRQs when the gpio chip device is removed drivers/gpio/gpiolib-cdev.c | 33 ++++++++++++++++++++++----------- drivers/gpio/gpiolib.c | 8 +++++++- 2 files changed, 29 insertions(+), 12 deletions(-)