linux-kernel - [PATCH 5.2 400/413] intel_th: msu: Fix single mode with disabled IOMMU

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190724191803.455107597@linuxfoundation.org>
Date:   Wed, 24 Jul 2019 21:21:31 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Ammy Yi <ammy.yi@...el.com>
Subject: [PATCH 5.2 400/413] intel_th: msu: Fix single mode with disabled IOMMU

From: Alexander Shishkin <alexander.shishkin@...ux.intel.com>

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@...ux.intel.com>
Fixes: 4e0eaf239fb3 ("intel_th: msu: Fix single mode with IOMMU")
Reviewed-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Reported-by: Ammy Yi <ammy.yi@...el.com>
Cc: stable <stable@...r.kernel.org>
Link: https://lore.kernel.org/r/20190621161930.60785-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/hwtracing/intel_th/msu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/hwtracing/intel_th/msu.c
+++ b/drivers/hwtracing/intel_th/msu.c
@@ -667,7 +667,7 @@ static int msc_buffer_contig_alloc(struc
 		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;