[PATCH v8 15/25] alpha/PCI: Remove WARN from __pci_mmap_fits() and __legacy_mmap_fits()
From: Krzysztof Wilczyński <kwilczynski@kernel.org>
Date: 2026-06-19 08:52:59
Also in:
linux-alpha, linux-pci
Subsystem:
alpha port, the rest · Maintainers:
Richard Henderson, Matt Turner, Magnus Lindholm, Linus Torvalds
Remove the WARN() that fires when userspace attempts to mmap beyond
the BAR bounds. The check still returns 0 to reject the mapping,
but the warning is excessive for normal operation.
A similar warning was removed from the PCI core in the commit
3b519e4ea618 ("PCI: fix size checks for mmap() on /proc/bus/pci files").
Tested-by: Magnus Lindholm <linmag7@gmail.com>
Tested-by: Shivaprasad G Bhat <redacted>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Acked-by: Magnus Lindholm <linmag7@gmail.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
---
arch/alpha/kernel/pci-sysfs.c | 23 +++++------------------
1 file changed, 5 insertions(+), 18 deletions(-)
diff --git a/arch/alpha/kernel/pci-sysfs.c b/arch/alpha/kernel/pci-sysfs.c
index 8802f955256e..6cf688621ea9 100644
--- a/arch/alpha/kernel/pci-sysfs.c
+++ b/arch/alpha/kernel/pci-sysfs.c@@ -48,13 +48,7 @@ static int __pci_mmap_fits(struct pci_dev *pdev, int num, start = vma->vm_pgoff; size = ((len - 1) >> (PAGE_SHIFT - shift)) + 1; - if (start < size && size - start >= nr) - return 1; - WARN(1, "process \"%s\" tried to map%s 0x%08lx-0x%08lx on %s BAR %d " - "(size 0x%08lx)\n", - current->comm, sparse ? " sparse" : "", start, start + nr, - pci_name(pdev), num, size); - return 0; + return start < size && size - start >= nr; } /**
@@ -257,9 +251,8 @@ int pci_create_resource_files(struct pci_dev *pdev) /* Legacy I/O bus mapping stuff. */ -static int __legacy_mmap_fits(struct pci_controller *hose, - struct vm_area_struct *vma, - unsigned long res_size, int sparse) +static int __legacy_mmap_fits(struct vm_area_struct *vma, + unsigned long res_size) { unsigned long nr, start, size;
@@ -267,13 +260,7 @@ 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; } static inline int has_sparse(struct pci_controller *hose,
@@ -296,7 +283,7 @@ int pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma, res_size = (mmap_type == pci_mmap_mem) ? bus->legacy_mem->size : bus->legacy_io->size; - if (!__legacy_mmap_fits(hose, vma, res_size, sparse)) + if (!__legacy_mmap_fits(vma, res_size)) return -EINVAL; return hose_mmap_page_range(hose, vma, mmap_type, sparse);
--
2.54.0