linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Joe Jin <joe.jin@oracle.com>
To: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	"DONGLI.ZHANG" <dongli.zhang@oracle.com>,
	konrad@kernel.org, Christoph Helwig <hch@lst.de>,
	John Sobecki <john.sobecki@oracle.com>,
	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>,
	"linux-kernel@vger.kernel.org\"" <linux-kernel@vger.kernel.org>
Subject: [PATCH] xen-swiotlb: exchange memory with Xen only when pages are contiguous
Date: Tue, 23 Oct 2018 20:09:04 -0700	[thread overview]
Message-ID: <bb6d87b4-c371-c6c0-8c48-bc95df018ad1@oracle.com> (raw)

Commit 4855c92dbb7 "xen-swiotlb: fix the check condition for
xen_swiotlb_free_coherent" only fixed memory address check condition
on xen_swiotlb_free_coherent(), when memory was not physically
contiguous and tried to exchanged with Xen via 
xen_destroy_contiguous_region it will lead kernel panic.

The correct check condition should be memory is in DMA area and
physically contiguous.

Thank you Boris for pointing it out.

Signed-off-by: Joe Jin <joe.jin@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christoph Helwig <hch@lst.de>
Cc: Dongli Zhang <dongli.zhang@oracle.com>
Cc: John Sobecki <john.sobecki@oracle.com>
---
 drivers/xen/swiotlb-xen.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index f5c1af4ce9ab..aed92fa019f9 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -357,8 +357,8 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
 	/* Convert the size to actually allocated. */
 	size = 1UL << (order + XEN_PAGE_SHIFT);
 
-	if (((dev_addr + size - 1 <= dma_mask)) ||
-	    range_straddles_page_boundary(phys, size))
+	if ((dev_addr + size - 1 <= dma_mask) &&
+	    !range_straddles_page_boundary(phys, size))
 		xen_destroy_contiguous_region(phys, order);
 
 	xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs);
-- 
2.17.1 (Apple Git-112)


             reply	other threads:[~2018-10-24  3:09 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-24  3:09 Joe Jin [this message]
2018-10-24 13:02 ` Konrad Rzeszutek Wilk
2018-10-24 13:57   ` Boris Ostrovsky
2018-10-24 14:43     ` Joe Jin
2018-10-25 11:45       ` Boris Ostrovsky
2018-10-25 14:23         ` Joe Jin
2018-10-25 16:10           ` Boris Ostrovsky
2018-10-25 16:28             ` Joe Jin
2018-10-25 18:56               ` Joe Jin
2018-10-26  7:48                 ` Christoph Helwig
2018-10-26  8:54                   ` Dongli Zhang
2018-10-26 14:48                     ` Joe Jin
2018-10-26 14:40                   ` Joe Jin
2018-10-30  2:51                 ` Joe Jin
     [not found]                   ` <57e5593233c64dc0a36c7d4c750a1ed4@AMSPEX02CL03.citrite.net>
2018-10-30 14:12                     ` [Xen-devel] " Joe Jin
     [not found]                       ` <097f1f6f16f7415aa3a52a7c4f5e52dc@AMSPEX02CL03.citrite.net>
2018-10-30 14:48                         ` Joe Jin
2018-10-24 16:05   ` Joe Jin

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=bb6d87b4-c371-c6c0-8c48-bc95df018ad1@oracle.com \
    --to=joe.jin@oracle.com \
    --cc=boris.ostrovsky@oracle.com \
    --cc=dongli.zhang@oracle.com \
    --cc=hch@lst.de \
    --cc=john.sobecki@oracle.com \
    --cc=konrad.wilk@oracle.com \
    --cc=konrad@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=xen-devel@lists.xenproject.org \
    --subject='Re: [PATCH] xen-swiotlb: exchange memory with Xen only when pages are contiguous' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).