Re: [PATCH v2] PCI: octep: Size the interrupt name buffer for the full format range

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Nov 06, 2026 at 09:21:26AM +0800, xujiahao wrote:
> octep_hp_request_irq() formats the interrupt name with "octep_hp_%d"
> into a 16-byte array.  The prefix is 9 bytes and a full-range %d
> argument can add up to 11 more, so the worst case needs 21 bytes
> including the terminator and 0-day reports:
> 
>   drivers/pci/hotplug/octep_hp.c:312:53: warning: '%d' directive output may be truncated writing between 1 and 10 bytes into a region of size 7 [-Wformat-truncation=]
>   note: 'snprintf' output between 11 and 20 bytes into a destination of size 16
> 
> The values passed today are OCTEP_HP_INTR_ENA (0) and OCTEP_HP_INTR_DIS (1),
> so no truncation actually happens, but the buffer carries no margin over the
> format's worst case.  Give it the room so the warning stops coming back from
> builds that cannot narrow the argument.
> 
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202507261457.SXXHOjUk-lkp@intel.com/
> Signed-off-by: xujiahao <xujiahao@cmss.chinamobile.com>

Applied to pci/hotplug for v7.5, thank you!

> ---
> Changes in v2:
> - Keep the compiler warning text on single lines so it stays greppable in
>   the git log (Bjorn Helgaas)
> - Capitalize the subject to match drivers/pci/hotplug/ style (Bjorn Helgaas)
> - Spell out the enum values passed to the format (Bjorn Helgaas)
> ---
>  drivers/pci/hotplug/octep_hp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/hotplug/octep_hp.c b/drivers/pci/hotplug/octep_hp.c
> index a0a7f9ccb..801c080e6 100644
> --- a/drivers/pci/hotplug/octep_hp.c
> +++ b/drivers/pci/hotplug/octep_hp.c
> @@ -52,7 +52,7 @@ struct octep_hp_slot {
>  struct octep_hp_intr_info {
>  	enum octep_hp_intr_type type;
>  	int number;
> -	char name[16];
> +	char name[24];
>  };
>  
>  struct octep_hp_controller {
> -- 
> 2.43.0
> 
> 
>