Re: [PATCH -next 2/2] sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl

[libaokun (A)]

在 2021/11/19 23:43, Sergei Shtylyov 写道:
> Hello!
>
> On 19.11.2021 7:11, Baokun Li wrote:
>
> > Trying to remove the fsl-sata module in the PPC64 GNU/Linux
> > leads to the following warning:
> >   ------------[ cut here ]------------
> >   remove_proc_entry: removing non-empty directory 'irq/69',
> >     leaking at least 'fsl-sata[ff0221000.sata]'
> >   WARNING: CPU: 3 PID: 1048 at fs/proc/generic.c:722
> >     .remove_proc_entry+0x20c/0x220
> >   IRQMASK: 0
> >   NIP [c00000000033826c] .remove_proc_entry+0x20c/0x220
> >   LR [c000000000338268] .remove_proc_entry+0x208/0x220
> >   Call Trace:
> >    .remove_proc_entry+0x208/0x220 (unreliable)
> >    .unregister_irq_proc+0x104/0x140
> >    .free_desc+0x44/0xb0
> >    .irq_free_descs+0x9c/0xf0
> >    .irq_dispose_mapping+0x64/0xa0
> >    .sata_fsl_remove+0x58/0xa0 [sata_fsl]
> >    .platform_drv_remove+0x40/0x90
> >    .device_release_driver_internal+0x160/0x2c0
> >    .driver_detach+0x64/0xd0
> >    .bus_remove_driver+0x70/0xf0
> >    .driver_unregister+0x38/0x80
> >    .platform_driver_unregister+0x14/0x30
> >    .fsl_sata_driver_exit+0x18/0xa20 [sata_fsl]
> >   ---[ end trace 0ea876d4076908f5 ]---
> >
> > The driver creates the mapping by calling irq_of_parse_and_map(),
> > so it also has to dispose the mapping. But the easy way out is to
> > simply use platform_get_irq() instead of irq_of_parse_map().
>
>   Not that easy. :-)
>
> > In this case the mapping is not managed by the device but by
> > the of core, so the device has not to dispose the mapping.
> >
> > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> > Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx>
> > ---
> >   drivers/ata/sata_fsl.c | 4 +---
> >   1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/ata/sata_fsl.c b/drivers/ata/sata_fsl.c
> > index 30759fd1c3a2..011daac4a14e 100644
> > --- a/drivers/ata/sata_fsl.c
> > +++ b/drivers/ata/sata_fsl.c
> > @@ -1493,7 +1493,7 @@ static int sata_fsl_probe(struct 
> > platform_device *ofdev)
> >       host_priv->ssr_base = ssr_base;
> >       host_priv->csr_base = csr_base;
> >   -    irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
> > +    irq = platform_get_irq(ofdev, 0);
> >       if (!irq) {
>
>     if (irq < 0) {
>
>   platform_get_irq() returns negative error codes, not 0 on failure.
>
> [...]
>
> MBR, Sergey
> .

I didn't notice the change in this return value, and the test didn't 
cover the error branch.

Thank you very much for your advice.

I'm about to send a patch v2 with the changes suggested by you.

--
With Best Regards,
Baokun Li
.