@@ -287,6 +287,12 @@ struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
"desc %p not ACKed\n", tx_desc);
}
+ if (ret == NULL) {
+ dev_dbg(bdma_chan->dchan.device->dev,
+ "%s: unable to obtain tx descriptor\n", __func__);
+ goto err_out;
+ }
+
i = bdma_chan->wr_count_next % bdma_chan->bd_num;
if (i == bdma_chan->bd_num - 1) {
i = 0;
@@ -297,7 +303,7 @@ struct tsi721_tx_desc *tsi721_desc_get(struct tsi721_bdma_chan *bdma_chan)
tx_desc->txd.phys = bdma_chan->bd_phys +
i * sizeof(struct tsi721_dma_desc);
tx_desc->hw_desc = &((struct tsi721_dma_desc *)bdma_chan->bd_base)[i];
-
+err_out:
spin_unlock_bh(&bdma_chan->lock);
return ret;
This is a note to let you know that I have just added a patch titled rapidio/tsi721_dma: fix failure to obtain transaction descriptor to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11.6. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 4a4f762ed817847e9b8cabdae7f59803393003a3 Mon Sep 17 00:00:00 2001 From: Alexandre Bounine <alexandre.bounine@idt.com> Date: Wed, 30 Jul 2014 16:08:26 -0700 Subject: rapidio/tsi721_dma: fix failure to obtain transaction descriptor commit 0193ed8225e1a79ed64632106ec3cc81798cb13c upstream. This is a bug fix for the situation when function tsi721_desc_get() fails to obtain a free transaction descriptor. The bug usually results in a memory access crash dump when data transfer scatter-gather list has more entries than size of hardware buffer descriptors ring. This fix ensures that error is properly returned to a caller instead of an invalid entry. This patch is applicable to kernel versions starting from v3.5. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com> Cc: Stef van Os <stef.van.os@prodrive-technologies.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/rapidio/devices/tsi721_dma.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) -- 1.9.1