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34 lines
1.4 KiB
Diff
34 lines
1.4 KiB
Diff
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From 4967ec844a52498af050b1176fedeca37aca111e Mon Sep 17 00:00:00 2001
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From: Robin Gong <yibin.gong@nxp.com>
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Date: Tue, 16 Oct 2018 01:06:29 +0800
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Subject: [PATCH] MLK-19931-1: dmaengine: fsl-edma-v3: fix potential kernel
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crash in cyclic
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There is one potential race condition in virt-dma framework as below:
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terminate dma channel after the last dma done interrupt, but before
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vchan_complete tasklet scheduled, thus the free-ed 'vd' (free in
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fsl_edma3_terminate_all) maybe still be touched in vchan_complete()
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which cause NULL pointer crash.
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Kernel community noticed this issue and fix it at virt-dma level:
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https://patchwork.kernel.org/patch/10057791/. To avoid backport too
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much patches, set 'vc->cyclic = NULL' in terminate dma channel
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interfaces to fix such issue easily.
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Signed-off-by: Robin Gong <yibin.gong@nxp.com>
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Acked-by: Fugang Duan <fugang.duan@nxp.com>
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(cherry picked from commit 18c9083826400a2ef731496391a0b5e71d461a5f)
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---
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drivers/dma/fsl-edma-v3.c | 1 +
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1 file changed, 1 insertion(+)
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--- a/drivers/dma/fsl-edma-v3.c
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+++ b/drivers/dma/fsl-edma-v3.c
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@@ -285,6 +285,7 @@ static int fsl_edma3_terminate_all(struc
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fsl_chan->edesc = NULL;
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fsl_chan->idle = true;
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fsl_chan->used = false;
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+ fsl_chan->vchan.cyclic = NULL;
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vchan_get_all_descriptors(&fsl_chan->vchan, &head);
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spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
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vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
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