7f72346689
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 <alexander.shishkin@linux.intel.com>
Fixes: 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reported-by: Ammy Yi <ammy.yi@intel.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190621161930.60785-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.