From a4d4e55e34079bc72fbf2f63e9babcf67f8fe195 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Tue, 10 May 2022 13:17:32 -0400 Subject: [PATCH] dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC [ Upstream commit 84bc4f1dbbbb5f8aa68706a96711dccb28b518e5 ] We observed the error "cacheline tracking ENOMEM, dma-debug disabled" during a light system load (copying some files). The reason for this error is that the dma_active_cacheline radix tree uses GFP_NOWAIT allocation - so it can't access the emergency memory reserves and it fails as soon as anybody reaches the watermark. This patch changes GFP_NOWAIT to GFP_ATOMIC, so that it can access the emergency memory reserves. Signed-off-by: Mikulas Patocka Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- kernel/dma/debug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 9c9a5b12f92f..7c6cd00d0fca 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -469,7 +469,7 @@ void debug_dma_dump_mappings(struct device *dev) * At any time debug_dma_assert_idle() can be called to trigger a * warning if any cachelines in the given page are in the active set. */ -static RADIX_TREE(dma_active_cacheline, GFP_NOWAIT); +static RADIX_TREE(dma_active_cacheline, GFP_ATOMIC); static DEFINE_SPINLOCK(radix_lock); #define ACTIVE_CACHELINE_MAX_OVERLAP ((1 << RADIX_TREE_MAX_TAGS) - 1) #define CACHELINE_PER_PAGE_SHIFT (PAGE_SHIFT - L1_CACHE_SHIFT)