Commit c7084b35 authored Aug 20, 2009 by Casey Dahlin Committed by Ingo Molnar Aug 21, 2009

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>

parent 451d7400

lib/swiotlb.c

+9 −6

Original line number	Diff line number	Diff line
		@@ -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");
		}

		/*

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