PCI: use pr_warn_once for ACS parameter parse failure

[PATCH] PCI: use pr_warn_once for ACS parameter parse failure

Posted by Richard Cheng 3 weeks, 5 days ago

When the ACS command line parameter cannot be parsed, the kernel skips
applying the requested ACS override. This indicates an invalid boot
parameter and should not be logged at informational level.

Use pr_warn_once() so the message is surfaced as a warning while still
avoiding repeated log spam during device enumeration.

Signed-off-by: Richard Cheng <icheng@nvidia.com>
Acked-by: Tushar Dave <tdave@nvidia.com>
---
 drivers/pci/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 13dbb405dc31..4e3b051c0f5f 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -953,7 +953,7 @@ static void __pci_config_acs(struct pci_dev *dev, struct pci_acs *caps,
 
 		ret = pci_dev_str_match(dev, p, &p);
 		if (ret < 0) {
-			pr_info_once("PCI: Can't parse ACS command line parameter\n");
+			pr_warn_once("PCI: Can't parse ACS command line parameter\n");
 			break;
 		} else if (ret == 1) {
 			/* Found a match */
-- 
2.51.0

Re: [PATCH] PCI: use pr_warn_once for ACS parameter parse failure

Posted by Bjorn Helgaas 3 weeks, 4 days ago

On Thu, Mar 12, 2026 at 07:54:41PM +0800, Richard Cheng wrote:
> When the ACS command line parameter cannot be parsed, the kernel skips
> applying the requested ACS override. This indicates an invalid boot
> parameter and should not be logged at informational level.
> 
> Use pr_warn_once() so the message is surfaced as a warning while still
> avoiding repeated log spam during device enumeration.
> 
> Signed-off-by: Richard Cheng <icheng@nvidia.com>
> Acked-by: Tushar Dave <tdave@nvidia.com>

Applied to pci/misc for v7.1, thanks!

> ---
>  drivers/pci/pci.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 13dbb405dc31..4e3b051c0f5f 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -953,7 +953,7 @@ static void __pci_config_acs(struct pci_dev *dev, struct pci_acs *caps,
>  
>  		ret = pci_dev_str_match(dev, p, &p);
>  		if (ret < 0) {
> -			pr_info_once("PCI: Can't parse ACS command line parameter\n");
> +			pr_warn_once("PCI: Can't parse ACS command line parameter\n");
>  			break;
>  		} else if (ret == 1) {
>  			/* Found a match */
> -- 
> 2.51.0
> 
>