Re: [PATCH -next V4 2/2] sata_fsl: fix warning in remove_proc_entry when rmmod sata_fsl

From: libaokun (A)
Date: Thu Nov 25 2021 - 20:38:47 EST


在 2021/11/26 7:47, Damien Le Moal 写道:
On 2021/11/23 10:41, 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(). Also
we should adapt return value checking and propagate error values.

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.

Fixes: faf0b2e5afe7 ("drivers/ata: add support to Freescale 3.0Gbps SATA Controller")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx>
---
V1->V2:
Adapt return value checking and propagate error values.
V2->V3:
Add fixed and CC stable.

drivers/ata/sata_fsl.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/ata/sata_fsl.c b/drivers/ata/sata_fsl.c
index 2eb216792695..8e7c49793f91 100644
--- a/drivers/ata/sata_fsl.c
+++ b/drivers/ata/sata_fsl.c
@@ -1490,8 +1490,9 @@ 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);
- if (!irq) {
+ irq = platform_get_irq(ofdev, 0);
+ if (irq < 0) {
+ retval = irq;
dev_err(&ofdev->dev, "invalid irq from platform\n");
Nit: platform_get_irq() already prints an error message in case of failure. So
while at it, you could remove this one here.

I've seen a similar change in cf9441adb1a3("ASoC: Remove dev_err() usage after platform_get_irq()"),

but I'm not sure if it needs to be changed here. Now that you have pointed out the problem,

I will send a patch V5 with the changes suggested by you. Thank you!



goto error_exit_with_cleanup;
}
@@ -1567,8 +1568,6 @@ static int sata_fsl_remove(struct platform_device *ofdev)
ata_host_detach(host);
- irq_dispose_mapping(host_priv->irq);
-
return 0;
}


--
With Best Regards,
Baokun Li
.