+ lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up.patch added to -mm tree

+ lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up.patch added to -mm tree

[akpm]

The patch titled
     lib/swiotlb.c: fix strange panic message selection logic when swiotlb fills up
has been added to the -mm tree.  Its filename is
     lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up.patch

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------------------------------------------------------
Subject: lib/swiotlb.c: fix strange panic message selection logic when swiotlb fills up
From: Casey Dahlin <cdahlin@redhat.com>

swiotlb_full in lib/swiotlb.c throws one of two panic messages based on
whether the direction of transfer is from the device or to the device. 
The logic around this is somewhat weird in the case of bidirectional
transfers.  It appears to want to throw both in succession, but since its
a panic only the first makes it.

This patch adds a third, separate error for DMA_BIDIRECTIONAL to make
things a bit clearer.

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/swiotlb.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff -puN lib/swiotlb.c~lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up lib/swiotlb.c
--- a/lib/swiotlb.c~lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up
+++ a/lib/swiotlb.c
@@ -581,12 +581,15 @@ swiotlb_full(struct device *dev, size_t 
 	printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
 	       "device %s\n", size, dev ? dev_name(dev) : "?");
 
-	if (size > io_tlb_overflow && do_panic) {
-		if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
-			panic("DMA: Memory would be corrupted\n");
-		if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
-			panic("DMA: Random memory would be DMAed\n");
-	}
+	if (size <= io_tlb_overflow || !do_panic)
+		return;
+
+	if (dir == DMA_BIDIRECTIONAL)
+		panic("DMA: Random memory could be corrupted or DMAed\n");
+	if (dir == DMA_FROM_DEVICE)
+		panic("DMA: Memory would be corrupted\n");
+	if (dir == DMA_TO_DEVICE)
+		panic("DMA: Random memory would be DMAed\n");
 }
 
 /*
_

Patches currently in -mm which might be from cdahlin@redhat.com are

lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up.patch
lib-swiotlbc-fix-strange-panic-message-selection-logic-when-swiotlb-fills-up-fix.patch

[tip:core/iommu] lib/swiotlb.c: Fix strange panic message selection logic when swiotlb fills up

[tip-bot for Casey Dahlin]

Commit-ID:  c7084b35eb1a4d3353a501508baf9d3d82822c93
Gitweb:     http://git.kernel.org/tip/c7084b35eb1a4d3353a501508baf9d3d82822c93
Author:     Casey Dahlin <cdahlin@redhat.com>
AuthorDate: Thu, 20 Aug 2009 16:27:56 -0700
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 21 Aug 2009 10:36:03 +0200

lib/swiotlb.c: Fix strange panic message selection logic when swiotlb fills up

swiotlb_full() in lib/swiotlb.c throws one of two panic messages
based on whether the direction of transfer is from the device
or to the device. The logic around this is somewhat weird in
the case of bidirectional transfers. It appears to want to
throw both in succession, but since its a panic only the first
makes it.

This patch adds a third, separate error for DMA_BIDIRECTIONAL
to make things a bit clearer.

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
[ further fixed the error message ]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <200908202327.n7KNRuqK001504@imap1.linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


---
 lib/swiotlb.c |   15 +++++++++------
 1 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 9e2fe3e..ac25cd2 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -581,12 +581,15 @@ swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
 	printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
 	       "device %s\n", size, dev ? dev_name(dev) : "?");
 
-	if (size > io_tlb_overflow && do_panic) {
-		if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
-			panic("DMA: Memory would be corrupted\n");
-		if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
-			panic("DMA: Random memory would be DMAed\n");
-	}
+	if (size <= io_tlb_overflow || !do_panic)
+		return;
+
+	if (dir == DMA_BIDIRECTIONAL)
+		panic("DMA: Random memory could be DMA accessed\n");
+	if (dir == DMA_FROM_DEVICE)
+		panic("DMA: Random memory could be DMA written\n");
+	if (dir == DMA_TO_DEVICE)
+		panic("DMA: Random memory could be DMA read\n");
 }
 
 /*