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authorKees Cook2022-03-09 09:37:31 -0800
committerKees Cook2022-03-31 11:19:25 -0700
commit229a08a4f4e4f9949801cc39b6480ddc9c487183 (patch)
tree99ba87442ac1db9a7b64b2d998bf4e295ee6bdea /arch
parentef3e787c21d1efcd297f0cf2e9535e76188fb831 (diff)
ARM/dma-mapping: Remove CMA code when not built with CMA
The MAX_CMA_AREAS could be set to 0, which would result in code that would attempt to operate beyond the end of a zero-sized array. If CONFIG_CMA is disabled, just remove this code entirely. Found when building arm on GCC 10.x for several defconfigs (e.g. axm55xx_defconfig) under -Warray-bounds: arch/arm/mm/dma-mapping.c:396:22: warning: array subscript <unknown> is outside array bounds of 'struct dma_contig_early_reserve[0]' [-Warray-bounds] 396 | dma_mmu_remap[dma_mmu_remap_num].size = size; | ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~ arch/arm/mm/dma-mapping.c:389:40: note: while referencing 'dma_mmu_remap' 389 | static struct dma_contig_early_reserve dma_mmu_remap[MAX_CMA_AREAS] __initdata; | ^~~~~~~~~~~~~ Cc: Russell King <linux@armlinux.org.uk> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Martin Oliveira <martin.oliveira@eideticom.com> Cc: David Hildenbrand <david@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Zi Yan <ziy@nvidia.com> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/all/6243ee60.1c69fb81.16de6.7dbf@mx.google.com/ Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/lkml/20220310070041.GA24874@lst.de Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/lkml/9059fa71-330f-f04f-b155-2850abb72a71@redhat.com
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mm/dma-mapping.c2
-rw-r--r--arch/arm/mm/mm.h4
2 files changed, 6 insertions, 0 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 4b61541853ea..82ffac621854 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -381,6 +381,7 @@ out:
*/
postcore_initcall(atomic_pool_init);
+#ifdef CONFIG_CMA_AREAS
struct dma_contig_early_reserve {
phys_addr_t base;
unsigned long size;
@@ -435,6 +436,7 @@ void __init dma_contiguous_remap(void)
iotable_init(&map, 1);
}
}
+#endif
static int __dma_update_pte(pte_t *pte, unsigned long addr, void *data)
{
diff --git a/arch/arm/mm/mm.h b/arch/arm/mm/mm.h
index 9ff683612f2a..d7ffccb7fea7 100644
--- a/arch/arm/mm/mm.h
+++ b/arch/arm/mm/mm.h
@@ -88,6 +88,10 @@ extern phys_addr_t arm_lowmem_limit;
void __init bootmem_init(void);
void arm_mm_memblock_reserve(void);
+#ifdef CONFIG_CMA_AREAS
void dma_contiguous_remap(void);
+#else
+static inline void dma_contiguous_remap(void) { }
+#endif
unsigned long __clear_cr(unsigned long mask);