diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/dma/debug.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 3dfed51c3d9a..c38efc1ac8d6 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -1074,6 +1074,29 @@ static void check_unmap(struct dma_debug_entry *ref) type2name[entry->type]); } + /* + * This may be no bug in reality - but DMA API still expects + * that entry is unmapped with same attributes as it was mapped. + * + * DMA_ATTR_UNMAP_VALID lists the attributes that must be identical + * between map and unmap. Any attribute outside this set (e.g. + * DMA_ATTR_NO_WARN, DMA_ATTR_SKIP_CPU_SYNC) is allowed to differ. + */ +#define DMA_ATTR_UNMAP_VALID \ + (DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_FORCE_CONTIGUOUS | \ + DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT | DMA_ATTR_PRIVILEGED | \ + DMA_ATTR_CC_SHARED) + if ((ref->attrs & DMA_ATTR_UNMAP_VALID) != + (entry->attrs & DMA_ATTR_UNMAP_VALID)) { + err_printk(ref->dev, entry, + "device driver frees " + "DMA memory with different attributes " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with 0x%lx] [unmapped with 0x%lx]\n", + ref->dev_addr, ref->size, entry->attrs, ref->attrs); + } +#undef DMA_ATTR_UNMAP_VALID + hash_bucket_del(entry); put_hash_bucket(bucket, flags); |