[PATCH] PCI: switchtec: Fix an error handling path in switchtec_pci_probe()

[PATCH] PCI: switchtec: Fix an error handling path in switchtec_pci_probe()

[Christophe JAILLET]

The commit in Fixes changed the logic on how resources are released and
introduced a new switchtec_exit_pci() that need to be called explicitly in
order to undo a corresponding switchtec_init_pci().

This was done in the remove function, but not in the probe.

Fix the probe now.

Fixes: df25461119d9 ("PCI: switchtec: Fix stdev_release() crash after surprise hot remove")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/pci/switch/switchtec.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index 1804794d0e68..5a4adf6c04cf 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -1672,7 +1672,7 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
 	rc = switchtec_init_isr(stdev);
 	if (rc) {
 		dev_err(&stdev->dev, "failed to init isr.\n");
-		goto err_put;
+		goto err_exit_pci;
 	}
 
 	iowrite32(SWITCHTEC_EVENT_CLEAR |
@@ -1693,6 +1693,8 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
 
 err_devadd:
 	stdev_kill(stdev);
+err_exit_pci:
+	switchtec_exit_pci(stdev);
 err_put:
 	ida_free(&switchtec_minor_ida, MINOR(stdev->dev.devt));
 	put_device(&stdev->dev);
-- 
2.34.1

Re: [PATCH] PCI: switchtec: Fix an error handling path in switchtec_pci_probe()

[Bjorn Helgaas]

[+to Daniel, can you take a look?  If you like this, I'd like to
squash it into df25461119d9 and credit Christophe since that's not
upstream yet]

On Sun, Dec 24, 2023 at 03:30:01PM +0100, Christophe JAILLET wrote:
> The commit in Fixes changed the logic on how resources are released and
> introduced a new switchtec_exit_pci() that need to be called explicitly in
> order to undo a corresponding switchtec_init_pci().
> 
> This was done in the remove function, but not in the probe.
> 
> Fix the probe now.
> 
> Fixes: df25461119d9 ("PCI: switchtec: Fix stdev_release() crash after surprise hot remove")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
>  drivers/pci/switch/switchtec.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
> index 1804794d0e68..5a4adf6c04cf 100644
> --- a/drivers/pci/switch/switchtec.c
> +++ b/drivers/pci/switch/switchtec.c
> @@ -1672,7 +1672,7 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
>  	rc = switchtec_init_isr(stdev);
>  	if (rc) {
>  		dev_err(&stdev->dev, "failed to init isr.\n");
> -		goto err_put;
> +		goto err_exit_pci;
>  	}
>  
>  	iowrite32(SWITCHTEC_EVENT_CLEAR |
> @@ -1693,6 +1693,8 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
>  
>  err_devadd:
>  	stdev_kill(stdev);
> +err_exit_pci:
> +	switchtec_exit_pci(stdev);
>  err_put:
>  	ida_free(&switchtec_minor_ida, MINOR(stdev->dev.devt));
>  	put_device(&stdev->dev);
> -- 
> 2.34.1
> 

Re: [PATCH] PCI: switchtec: Fix an error handling path in switchtec_pci_probe()

[Daniel Stodden]

> On Dec 28, 2023, at 3:56 PM, Bjorn Helgaas <helgaas@kernel.org> wrote:
> 
> [+to Daniel, can you take a look?  If you like this, I'd like to
> squash it into df25461119d9 and credit Christophe since that's not
> upstream yet]

Thanks very much for fixing this, Christophe.

The fix looks correct to me. If it can still fold into the previous change, all the better.

Best,
Daniel

PS: without trying to complicate this thread, does one know idr.[ch] well enough to state
whether ida_free() could have gone into stdev_release()? The way the two idr_free calls have
been placed looks intentional. But stdev_release would look more obvious + cleaner to me.
Was only starting to wonder while reviewing the err_put side of this patch.

Re: [PATCH] PCI: switchtec: Fix an error handling path in switchtec_pci_probe()

[Bjorn Helgaas]

On Sun, Dec 24, 2023 at 03:30:01PM +0100, Christophe JAILLET wrote:
> The commit in Fixes changed the logic on how resources are released and
> introduced a new switchtec_exit_pci() that need to be called explicitly in
> order to undo a corresponding switchtec_init_pci().
> 
> This was done in the remove function, but not in the probe.
> 
> Fix the probe now.
> 
> Fixes: df25461119d9 ("PCI: switchtec: Fix stdev_release() crash after surprise hot remove")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

Applied to pci/switchtec for v6.9, thanks!

> ---
>  drivers/pci/switch/switchtec.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
> index 1804794d0e68..5a4adf6c04cf 100644
> --- a/drivers/pci/switch/switchtec.c
> +++ b/drivers/pci/switch/switchtec.c
> @@ -1672,7 +1672,7 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
>  	rc = switchtec_init_isr(stdev);
>  	if (rc) {
>  		dev_err(&stdev->dev, "failed to init isr.\n");
> -		goto err_put;
> +		goto err_exit_pci;
>  	}
>  
>  	iowrite32(SWITCHTEC_EVENT_CLEAR |
> @@ -1693,6 +1693,8 @@ static int switchtec_pci_probe(struct pci_dev *pdev,
>  
>  err_devadd:
>  	stdev_kill(stdev);
> +err_exit_pci:
> +	switchtec_exit_pci(stdev);
>  err_put:
>  	ida_free(&switchtec_minor_ida, MINOR(stdev->dev.devt));
>  	put_device(&stdev->dev);
> -- 
> 2.34.1
>