From ca38f0295578d682a6710d930d9dbb127639d104 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Mon, 29 Jul 2019 20:36:39 +0800 Subject: [PATCH] intel_th: msu: Fix single mode with disabled IOMMU commit 918b8646497b5dba6ae82d4a7325f01b258972b9 upstream. Commit 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU") switched the single mode code to use dma mapping pages obtained from the page allocator, but with IOMMU disabled, that may lead to using SWIOTLB bounce buffers and without additional sync'ing, produces empty trace buffers. Fix this by using a DMA32 GFP flag to the page allocation in single mode, as the device supports full 32-bit DMA addressing. Signed-off-by: Alexander Shishkin Fixes: 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU") Reviewed-by: Andy Shevchenko Reported-by: Ammy Yi Cc: stable Link: https://lore.kernel.org/r/20190621161930.60785-4-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang --- drivers/hwtracing/intel_th/msu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c index 8ff326c0c406..3cdf85b1ce4f 100644 --- a/drivers/hwtracing/intel_th/msu.c +++ b/drivers/hwtracing/intel_th/msu.c @@ -632,7 +632,7 @@ static int msc_buffer_contig_alloc(struct msc *msc, unsigned long size) goto err_out; ret = -ENOMEM; - page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); + page = alloc_pages(GFP_KERNEL | __GFP_ZERO | GFP_DMA32, order); if (!page) goto err_free_sgt; -- GitLab