From: Qian Cai <cai@lca.pw>
To: jroedel@suse.de
Cc: iommu@lists.linux-foundation.org, torvalds@linux-foundation.org,
hch@lst.de, linux-kernel@vger.kernel.org
Subject: [PATCH v2] iommu/amd: fix a crash in iova_magazine_free_pfns
Date: Thu, 11 Jul 2019 12:17:45 -0400 [thread overview]
Message-ID: <1562861865-23660-1-git-send-email-cai@lca.pw> (raw)
The commit b3aa14f02254 ("iommu: remove the mapping_error dma_map_ops
method") incorrectly changed the checking from dma_ops_alloc_iova() in
map_sg() causes a crash under memory pressure as dma_ops_alloc_iova()
never return DMA_MAPPING_ERROR on failure but 0, so the error handling
is all wrong.
kernel BUG at drivers/iommu/iova.c:801!
Workqueue: kblockd blk_mq_run_work_fn
RIP: 0010:iova_magazine_free_pfns+0x7d/0xc0
Call Trace:
free_cpu_cached_iovas+0xbd/0x150
alloc_iova_fast+0x8c/0xba
dma_ops_alloc_iova.isra.6+0x65/0xa0
map_sg+0x8c/0x2a0
scsi_dma_map+0xc6/0x160
pqi_aio_submit_io+0x1f6/0x440 [smartpqi]
pqi_scsi_queue_command+0x90c/0xdd0 [smartpqi]
scsi_queue_rq+0x79c/0x1200
blk_mq_dispatch_rq_list+0x4dc/0xb70
blk_mq_sched_dispatch_requests+0x249/0x310
__blk_mq_run_hw_queue+0x128/0x200
blk_mq_run_work_fn+0x27/0x30
process_one_work+0x522/0xa10
worker_thread+0x63/0x5b0
kthread+0x1d2/0x1f0
ret_from_fork+0x22/0x40
Fixes: b3aa14f02254 ("iommu: remove the mapping_error dma_map_ops method")
Signed-off-by: Qian Cai <cai@lca.pw>
---
v2: Fix the offensive commit directly.
drivers/iommu/amd_iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 73740b969e62..b607a92791d3 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2533,7 +2533,7 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
npages = sg_num_pages(dev, sglist, nelems);
address = dma_ops_alloc_iova(dev, dma_dom, npages, dma_mask);
- if (address == DMA_MAPPING_ERROR)
+ if (!address)
goto out_err;
prot = dir2prot(direction);
--
1.8.3.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
next reply other threads:[~2019-07-11 16:24 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-11 16:17 Qian Cai [this message]
2019-07-11 16:21 ` [PATCH v2] iommu/amd: fix a crash in iova_magazine_free_pfns Christoph Hellwig
2019-07-21 16:58 ` Linus Torvalds
2019-07-22 13:30 ` Joerg Roedel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1562861865-23660-1-git-send-email-cai@lca.pw \
--to=cai@lca.pw \
--cc=hch@lst.de \
--cc=iommu@lists.linux-foundation.org \
--cc=jroedel@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox