Re: [PATCH v7 15/24] alpha/PCI: Remove WARN from __pci_mmap_fits() and __legacy_mmap_fits()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] The `hose` parameter in `__legacy_mmap_fits()` is now unused.
--

commit 7cae102d6c390202438077326b2b816098a36a13
Author: Krzysztof Wilczyński <kwilczynski@kernel.org>

alpha/PCI: Remove WARN from __pci_mmap_fits() and __legacy_mmap_fits()

This commit removes the WARN() that triggers when userspace attempts to mmap
beyond the BAR bounds. The mapping is still rejected, but the warning is
suppressed to prevent excessive logging.

> diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c
> index 8802f955256ea..a8dade7d084bc 100644
> --- a/arch/alpha/kernel/pci-sysfs.c
> +++ b/arch/alpha/kernel/pci-sysfs.c
[ ... ]
> @@ -259,7 +253,7 @@ int pci_create_resource_files(struct pci_dev *pdev)
>  
>  static int __legacy_mmap_fits(struct pci_controller *hose,
>  			      struct vm_area_struct *vma,
> -			      unsigned long res_size, int sparse)
> +			      unsigned long res_size)

This isn't a bug, but since the WARN() statement that used hose->index was
removed below, is the hose parameter still needed? It appears to be completely
unused in the function body now.

>  {
>  	unsigned long nr, start, size;
>  
> @@ -267,13 +261,7 @@ static int __legacy_mmap_fits(struct pci_controller *hose,
>  	start = vma->vm_pgoff;
>  	size = ((res_size - 1) >> PAGE_SHIFT) + 1;
>  
> -	if (start < size && size - start >= nr)
> -		return 1;
> -	WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on hose %d "
> -		"(size 0x%08lx)\n",
> -		current->comm, sparse ? " sparse" : "", start, start + nr,
> -		hose->index, size);
> -	return 0;
> +	return start < size && size - start >= nr;
>  }

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260508043543.217179-1-kwilczynski@kernel.org?part=15