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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-08-10 10:19:05 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-08-10 10:19:05 -0700 |
| commit | 0409cc53c42129cfeeaea610d0ebb91934491dca (patch) | |
| tree | c74e903dbd2de74a4e4f9c9f018bb7e6f916db16 | |
| parent | 31b244460634c74430745a74e56f5c88c43f079b (diff) | |
| parent | bd44ca3de49cc1badcff7a96010fa2c64f04868c (diff) | |
| download | lwn-0409cc53c42129cfeeaea610d0ebb91934491dca.tar.gz lwn-0409cc53c42129cfeeaea610d0ebb91934491dca.zip | |
Merge tag 'dma-mapping-6.11-2024-08-10' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fix from Christoph Hellwig:
- avoid a deadlock with dma-debug and netconsole (Rik van Riel)
* tag 'dma-mapping-6.11-2024-08-10' of git://git.infradead.org/users/hch/dma-mapping:
dma-debug: avoid deadlock between dma debug vs printk and netconsole
| -rw-r--r-- | kernel/dma/debug.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index a6e3792b15f8..d570535342cb 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -416,8 +416,11 @@ static unsigned long long phys_addr(struct dma_debug_entry *entry) * dma_active_cacheline entry to track per event. dma_map_sg(), on the * other hand, consumes a single dma_debug_entry, but inserts 'nents' * entries into the tree. + * + * Use __GFP_NOWARN because the printk from an OOM, to netconsole, could end + * up right back in the DMA debugging code, leading to a deadlock. */ -static RADIX_TREE(dma_active_cacheline, GFP_ATOMIC); +static RADIX_TREE(dma_active_cacheline, GFP_ATOMIC | __GFP_NOWARN); 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) |