This is a note to let you know that I've just added the patch titled
swiotlb: suppress warning when __GFP_NOWARN is set
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: swiotlb-suppress-warning-when-__gfp_nowarn-is-set.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From d0bc0c2a31c95002d37c3cc511ffdcab851b3256 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= ckoenig.leichtzumerken@gmail.com Date: Thu, 4 Jan 2018 14:24:19 +0100 Subject: swiotlb: suppress warning when __GFP_NOWARN is set MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
From: Christian König ckoenig.leichtzumerken@gmail.com
commit d0bc0c2a31c95002d37c3cc511ffdcab851b3256 upstream.
TTM tries to allocate coherent memory in chunks of 2MB first to improve TLB efficiency and falls back to allocating 4K pages if that fails.
Suppress the warning when the 2MB allocations fails since there is a valid fall back path.
Signed-off-by: Christian König christian.koenig@amd.com Reported-by: Mike Galbraith efault@gmx.de Acked-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com Bug: https://bugs.freedesktop.org/show_bug.cgi?id=104082 Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- lib/swiotlb.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
--- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -585,7 +585,7 @@ phys_addr_t swiotlb_tbl_map_single(struc
not_found: spin_unlock_irqrestore(&io_tlb_lock, flags); - if (printk_ratelimit()) + if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size); return SWIOTLB_MAP_ERROR; found: @@ -712,6 +712,7 @@ void * swiotlb_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, gfp_t flags) { + bool warn = !(flags & __GFP_NOWARN); dma_addr_t dev_addr; void *ret; int order = get_order(size); @@ -737,8 +738,8 @@ swiotlb_alloc_coherent(struct device *hw * GFP_DMA memory; fall back on map_single(), which * will grab memory from the lowest available address range. */ - phys_addr_t paddr = map_single(hwdev, 0, size, - DMA_FROM_DEVICE, 0); + phys_addr_t paddr = map_single(hwdev, 0, size, DMA_FROM_DEVICE, + warn ? 0 : DMA_ATTR_NO_WARN); if (paddr == SWIOTLB_MAP_ERROR) goto err_warn;
@@ -768,9 +769,11 @@ swiotlb_alloc_coherent(struct device *hw return ret;
err_warn: - pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n", - dev_name(hwdev), size); - dump_stack(); + if (warn && printk_ratelimit()) { + pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n", + dev_name(hwdev), size); + dump_stack(); + }
return NULL; }
Patches currently in stable-queue which might be from ckoenig.leichtzumerken@gmail.com are
queue-4.14/dma-buf-fix-reservation_object_wait_timeout_rcu-once-more-v2.patch queue-4.14/swiotlb-suppress-warning-when-__gfp_nowarn-is-set.patch