[PATCH] dma debug: report -EEXIST errors in add_dma_entry

From: Hamza Mahfooz
Date: Tue May 18 2021 - 08:55:43 EST


Since, overlapping mappings are not supported by the DMA API we should
report an error if active_cacheline_insert returns -EEXIST.

Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Hamza Mahfooz <someguy@xxxxxxxxxxxxxxxxxxx>
---
kernel/dma/debug.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 14de1271463f..dadae6255d05 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -566,11 +566,9 @@ static void add_dma_entry(struct dma_debug_entry *entry)
if (rc == -ENOMEM) {
pr_err("cacheline tracking ENOMEM, dma-debug disabled\n");
global_disable = true;
+ } else if (rc == -EEXIST) {
+ pr_err("cacheline tracking EEXIST, overlapping mappings aren't supported\n");
}
-
- /* TODO: report -EEXIST errors here as overlapping mappings are
- * not supported by the DMA API
- */
}

static int dma_debug_create_entries(gfp_t gfp)
--
2.31.1