Re: [GIT PULL 3/4] intel_th: msu: Fix single mode with disabled IOMMU

From: Greg Kroah-Hartman
Date: Wed Jul 03 2019 - 11:36:25 EST

On Fri, Jun 21, 2019 at 07:19:29PM +0300, Alexander Shishkin wrote:
> 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 <alexander.shishkin@xxxxxxxxxxxxxxx>
> Fixes: 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU")
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Reported-by: Ammy Yi <ammy.yi@xxxxxxxxx>
> ---
> drivers/hwtracing/intel_th/msu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

You should have had a stable tag on here anyway...