Commit 173735c3 authored by Anthony Iliopoulos's avatar Anthony Iliopoulos Committed by Christoph Hellwig
Browse files

dma-debug: fix debugfs initialization order 

Due to link order, dma_debug_init is called before debugfs has a chance
to initialize (via debugfs_init which also happens in the core initcall
stage), so the directories for dma-debug are never created.

Decouple dma_debug_fs_init from dma_debug_init and defer its init until
core_initcall_sync (after debugfs has been initialized) while letting
dma-debug initialization occur as soon as possible to catch any early
mappings, as suggested in [1].

[1] https://lore.kernel.org/linux-iommu/YIgGa6yF%2Fadg8OSN@kroah.com/



Fixes: 15b28bbc ("dma-debug: move initialization to common code")
Signed-off-by: default avatarAnthony Iliopoulos <ailiop@suse.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 1d7db834

kernel/dma/debug.c

+4 −3
Original line number Diff line number Diff line
@@ -792,7 +792,7 @@ static int dump_show(struct seq_file *seq, void *v) 
}

DEFINE_SHOW_ATTRIBUTE(dump);



static void dma_debug_fs_init(void)

static int __init dma_debug_fs_init(void)

{

	struct dentry *dentry = debugfs_create_dir("dma-api", NULL);
@@ -805,7 +805,10 @@ static void dma_debug_fs_init(void) 
	debugfs_create_u32("nr_total_entries", 0444, dentry, &nr_total_entries);

	debugfs_create_file("driver_filter", 0644, dentry, NULL, &filter_fops);

	debugfs_create_file("dump", 0444, dentry, NULL, &dump_fops);



	return 0;

}

core_initcall_sync(dma_debug_fs_init);



static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry)

{
@@ -890,8 +893,6 @@ static int dma_debug_init(void) 
		spin_lock_init(&dma_entry_hash[i].lock);

	}



	dma_debug_fs_init();



	nr_pages = DIV_ROUND_UP(nr_prealloc_entries, DMA_DEBUG_DYNAMIC_ENTRIES);

	for (i = 0; i < nr_pages; ++i)

		dma_debug_create_entries(GFP_KERNEL);