From: "Jan Beulich" <JBeulich@suse.com>
To: xen-devel <xen-devel@lists.xenproject.org>
Cc: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>,
suravee.suthikulpanit@amd.com
Subject: [PATCH] AMD IOMMU: don't free page table prematurely
Date: Mon, 26 May 2014 11:16:43 +0100 [thread overview]
Message-ID: <538330AB0200007800015B2F@mail.emea.novell.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 1177 bytes --]
iommu_merge_pages() still wants to look at the next level page table,
the TLB flush necessary before freeing too happens in that function,
and if it fails no free should happen at all. Hence the freeing must
be done after that function returned successfully, not before it's
being called.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/drivers/passthrough/amd/iommu_map.c
+++ b/xen/drivers/passthrough/amd/iommu_map.c
@@ -691,8 +691,6 @@ int amd_iommu_map_page(struct domain *d,
if ( !iommu_update_pde_count(d, pt_mfn[merge_level],
gfn, mfn, merge_level) )
break;
- /* Deallocate lower level page table */
- free_amd_iommu_pgtable(mfn_to_page(pt_mfn[merge_level - 1]));
if ( iommu_merge_pages(d, pt_mfn[merge_level], gfn,
flags, merge_level) )
@@ -703,6 +701,9 @@ int amd_iommu_map_page(struct domain *d,
domain_crash(d);
return -EFAULT;
}
+
+ /* Deallocate lower level page table */
+ free_amd_iommu_pgtable(mfn_to_page(pt_mfn[merge_level - 1]));
}
out:
[-- Attachment #2: AMD-IOMMU-defer-merge-free.patch --]
[-- Type: text/plain, Size: 1219 bytes --]
AMD IOMMU: don't free page table prematurely
iommu_merge_pages() still wants to look at the next level page table,
the TLB flush necessary before freeing too happens in that function,
and if it fails no free should happen at all. Hence the freeing must
be done after that function returned successfully, not before it's
being called.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/drivers/passthrough/amd/iommu_map.c
+++ b/xen/drivers/passthrough/amd/iommu_map.c
@@ -691,8 +691,6 @@ int amd_iommu_map_page(struct domain *d,
if ( !iommu_update_pde_count(d, pt_mfn[merge_level],
gfn, mfn, merge_level) )
break;
- /* Deallocate lower level page table */
- free_amd_iommu_pgtable(mfn_to_page(pt_mfn[merge_level - 1]));
if ( iommu_merge_pages(d, pt_mfn[merge_level], gfn,
flags, merge_level) )
@@ -703,6 +701,9 @@ int amd_iommu_map_page(struct domain *d,
domain_crash(d);
return -EFAULT;
}
+
+ /* Deallocate lower level page table */
+ free_amd_iommu_pgtable(mfn_to_page(pt_mfn[merge_level - 1]));
}
out:
[-- Attachment #3: Type: text/plain, Size: 126 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
next reply other threads:[~2014-05-26 10:16 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-26 10:16 Jan Beulich [this message]
2014-05-26 15:55 ` [PATCH] AMD IOMMU: don't free page table prematurely Andrew Cooper
2014-05-28 5:20 ` Suravee Suthikulpanit
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=538330AB0200007800015B2F@mail.emea.novell.com \
--to=jbeulich@suse.com \
--cc=aravind.gopalakrishnan@amd.com \
--cc=suravee.suthikulpanit@amd.com \
--cc=xen-devel@lists.xenproject.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;
as well as URLs for NNTP newsgroup(s).