<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/include, branch v3.0.79</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>ipv6: do not clear pinet6 field</title>
<updated>2013-05-19T17:04:46+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2013-05-09T10:28:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1e74f2ea952f201c5ee5edce74daab21aea89b31'/>
<id>1e74f2ea952f201c5ee5edce74daab21aea89b31</id>
<content type='text'>
[ Upstream commit f77d602124d865c38705df7fa25c03de9c284ad2 ]

We have seen multiple NULL dereferences in __inet6_lookup_established()

After analysis, I found that inet6_sk() could be NULL while the
check for sk_family == AF_INET6 was true.

Bug was added in linux-2.6.29 when RCU lookups were introduced in UDP
and TCP stacks.

Once an IPv6 socket, using SLAB_DESTROY_BY_RCU is inserted in a hash
table, we no longer can clear pinet6 field.

This patch extends logic used in commit fcbdf09d9652c891
("net: fix nulls list corruptions in sk_prot_alloc")

TCP/UDP/UDPLite IPv6 protocols provide their own .clear_sk() method
to make sure we do not clear pinet6 field.

At socket clone phase, we do not really care, as cloning the parent (non
NULL) pinet6 is not adding a fatal race.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f77d602124d865c38705df7fa25c03de9c284ad2 ]

We have seen multiple NULL dereferences in __inet6_lookup_established()

After analysis, I found that inet6_sk() could be NULL while the
check for sk_family == AF_INET6 was true.

Bug was added in linux-2.6.29 when RCU lookups were introduced in UDP
and TCP stacks.

Once an IPv6 socket, using SLAB_DESTROY_BY_RCU is inserted in a hash
table, we no longer can clear pinet6 field.

This patch extends logic used in commit fcbdf09d9652c891
("net: fix nulls list corruptions in sk_prot_alloc")

TCP/UDP/UDPLite IPv6 protocols provide their own .clear_sk() method
to make sure we do not clear pinet6 field.

At socket clone phase, we do not really care, as cloning the parent (non
NULL) pinet6 is not adding a fatal race.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>macvlan: fix passthru mode race between dev removal and rx path</title>
<updated>2013-05-19T17:04:46+00:00</updated>
<author>
<name>Jiri Pirko</name>
<email>jiri@resnulli.us</email>
</author>
<published>2013-05-09T04:23:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d5bf240fa193989d605a715bda7cb3283b1abc89'/>
<id>d5bf240fa193989d605a715bda7cb3283b1abc89</id>
<content type='text'>
[ Upstream commit 233c7df0821c4190e2d3f4be0f2ca0ab40a5ed8c, note
  that I had to add list_first_or_null_rcu to rculist.h in order
  to accomodate this fix. ]

Currently, if macvlan in passthru mode is created and data are rxed and
you remove this device, following panic happens:

NULL pointer dereference at 0000000000000198
IP: [&lt;ffffffffa0196058&gt;] macvlan_handle_frame+0x153/0x1f7 [macvlan]

I'm using following script to trigger this:
&lt;script&gt;
while [ 1 ]
do
	ip link add link e1 name macvtap0 type macvtap mode passthru
	ip link set e1 up
	ip link set macvtap0 up
	IFINDEX=`ip link |grep macvtap0 | cut -f 1 -d ':'`
	cat /dev/tap$IFINDEX  &gt;/dev/null &amp;
	ip link del dev macvtap0
done
&lt;/script&gt;

I run this script while "ping -f" is running on another machine to send
packets to e1 rx.

Reason of the panic is that list_first_entry() is blindly called in
macvlan_handle_frame() even if the list was empty. vlan is set to
incorrect pointer which leads to the crash.

I'm fixing this by protecting port-&gt;vlans list by rcu and by preventing
from getting incorrect pointer in case the list is empty.

Introduced by: commit eb06acdc85585f2 "macvlan: Introduce 'passthru' mode to takeover the underlying device"

Signed-off-by: Jiri Pirko &lt;jiri@resnulli.us&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 233c7df0821c4190e2d3f4be0f2ca0ab40a5ed8c, note
  that I had to add list_first_or_null_rcu to rculist.h in order
  to accomodate this fix. ]

Currently, if macvlan in passthru mode is created and data are rxed and
you remove this device, following panic happens:

NULL pointer dereference at 0000000000000198
IP: [&lt;ffffffffa0196058&gt;] macvlan_handle_frame+0x153/0x1f7 [macvlan]

I'm using following script to trigger this:
&lt;script&gt;
while [ 1 ]
do
	ip link add link e1 name macvtap0 type macvtap mode passthru
	ip link set e1 up
	ip link set macvtap0 up
	IFINDEX=`ip link |grep macvtap0 | cut -f 1 -d ':'`
	cat /dev/tap$IFINDEX  &gt;/dev/null &amp;
	ip link del dev macvtap0
done
&lt;/script&gt;

I run this script while "ping -f" is running on another machine to send
packets to e1 rx.

Reason of the panic is that list_first_entry() is blindly called in
macvlan_handle_frame() even if the list was empty. vlan is set to
incorrect pointer which leads to the crash.

I'm fixing this by protecting port-&gt;vlans list by rcu and by preventing
from getting incorrect pointer in case the list is empty.

Introduced by: commit eb06acdc85585f2 "macvlan: Introduce 'passthru' mode to takeover the underlying device"

Signed-off-by: Jiri Pirko &lt;jiri@resnulli.us&gt;
Acked-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>if_cablemodem.h: Add parenthesis around ioctl macros</title>
<updated>2013-05-19T17:04:46+00:00</updated>
<author>
<name>Josh Boyer</name>
<email>jwboyer@redhat.com</email>
</author>
<published>2013-05-08T09:45:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1d81283ce68fb5f6841aeea620a133e5f9707e33'/>
<id>1d81283ce68fb5f6841aeea620a133e5f9707e33</id>
<content type='text'>
[ Upstream commit 4f924b2aa4d3cb30f07e57d6b608838edcbc0d88 ]

Protect the SIOCGCM* ioctl macros with parenthesis.

Reported-by: Paul Wouters &lt;pwouters@redhat.com&gt;
Signed-off-by: Josh Boyer &lt;jwboyer@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4f924b2aa4d3cb30f07e57d6b608838edcbc0d88 ]

Protect the SIOCGCM* ioctl macros with parenthesis.

Reported-by: Paul Wouters &lt;pwouters@redhat.com&gt;
Signed-off-by: Josh Boyer &lt;jwboyer@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: force a dst refcount when prequeue packet</title>
<updated>2013-05-19T17:04:42+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2013-04-25T01:34:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a0464b18acc3f17ff86aa25df34c5066a21c8291'/>
<id>a0464b18acc3f17ff86aa25df34c5066a21c8291</id>
<content type='text'>
[ Upstream commit 093162553c33e9479283e107b4431378271c735d ]

Before escaping RCU protected section and adding packet into
prequeue, make sure the dst is refcounted.

Reported-by: Mike Galbraith &lt;bitbucket@online.de&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 093162553c33e9479283e107b4431378271c735d ]

Before escaping RCU protected section and adding packet into
prequeue, make sure the dst is refcounted.

Reported-by: Mike Galbraith &lt;bitbucket@online.de&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipc: sysv shared memory limited to 8TiB</title>
<updated>2013-05-08T02:57:27+00:00</updated>
<author>
<name>Robin Holt</name>
<email>holt@sgi.com</email>
</author>
<published>2013-05-01T02:15:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9b2bdb66b65fcbdd4f3a3d08c28e4c46b4a59364'/>
<id>9b2bdb66b65fcbdd4f3a3d08c28e4c46b4a59364</id>
<content type='text'>
commit d69f3bad4675ac519d41ca2b11e1c00ca115cecd upstream.

Trying to run an application which was trying to put data into half of
memory using shmget(), we found that having a shmall value below 8EiB-8TiB
would prevent us from using anything more than 8TiB.  By setting
kernel.shmall greater than 8EiB-8TiB would make the job work.

In the newseg() function, ns-&gt;shm_tot which, at 8TiB is INT_MAX.

ipc/shm.c:
 458 static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 459 {
...
 465         int numpages = (size + PAGE_SIZE -1) &gt;&gt; PAGE_SHIFT;
...
 474         if (ns-&gt;shm_tot + numpages &gt; ns-&gt;shm_ctlall)
 475                 return -ENOSPC;

[akpm@linux-foundation.org: make ipc/shm.c:newseg()'s numpages size_t, not int]
Signed-off-by: Robin Holt &lt;holt@sgi.com&gt;
Reported-by: Alex Thorlton &lt;athorlton@sgi.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d69f3bad4675ac519d41ca2b11e1c00ca115cecd upstream.

Trying to run an application which was trying to put data into half of
memory using shmget(), we found that having a shmall value below 8EiB-8TiB
would prevent us from using anything more than 8TiB.  By setting
kernel.shmall greater than 8EiB-8TiB would make the job work.

In the newseg() function, ns-&gt;shm_tot which, at 8TiB is INT_MAX.

ipc/shm.c:
 458 static int newseg(struct ipc_namespace *ns, struct ipc_params *params)
 459 {
...
 465         int numpages = (size + PAGE_SIZE -1) &gt;&gt; PAGE_SHIFT;
...
 474         if (ns-&gt;shm_tot + numpages &gt; ns-&gt;shm_ctlall)
 475                 return -ENOSPC;

[akpm@linux-foundation.org: make ipc/shm.c:newseg()'s numpages size_t, not int]
Signed-off-by: Robin Holt &lt;holt@sgi.com&gt;
Reported-by: Alex Thorlton &lt;athorlton@sgi.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>net: fix incorrect credentials passing</title>
<updated>2013-05-01T15:56:38+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-04-19T15:32:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=73d2de1ad017f674ec21e57405e47028dbc884bf'/>
<id>73d2de1ad017f674ec21e57405e47028dbc884bf</id>
<content type='text'>
[ Upstream commit 83f1b4ba917db5dc5a061a44b3403ddb6e783494 ]

Commit 257b5358b32f ("scm: Capture the full credentials of the scm
sender") changed the credentials passing code to pass in the effective
uid/gid instead of the real uid/gid.

Obviously this doesn't matter most of the time (since normally they are
the same), but it results in differences for suid binaries when the wrong
uid/gid ends up being used.

This just undoes that (presumably unintentional) part of the commit.

Reported-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Serge E. Hallyn &lt;serge@hallyn.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 83f1b4ba917db5dc5a061a44b3403ddb6e783494 ]

Commit 257b5358b32f ("scm: Capture the full credentials of the scm
sender") changed the credentials passing code to pass in the effective
uid/gid instead of the real uid/gid.

Obviously this doesn't matter most of the time (since normally they are
the same), but it results in differences for suid binaries when the wrong
uid/gid ends up being used.

This just undoes that (presumably unintentional) part of the commit.

Reported-by: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Eric W. Biederman &lt;ebiederm@xmission.com&gt;
Cc: Serge E. Hallyn &lt;serge@hallyn.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Acked-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>netfilter: don't reset nf_trace in nf_reset()</title>
<updated>2013-05-01T15:56:37+00:00</updated>
<author>
<name>Patrick McHardy</name>
<email>kaber@trash.net</email>
</author>
<published>2013-04-05T18:42:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a57d91ae48c1bca556dcde0d0a6273f7d8fabe1e'/>
<id>a57d91ae48c1bca556dcde0d0a6273f7d8fabe1e</id>
<content type='text'>
[ Upstream commit 124dff01afbdbff251f0385beca84ba1b9adda68 ]

Commit 130549fe ("netfilter: reset nf_trace in nf_reset") added code
to reset nf_trace in nf_reset(). This is wrong and unnecessary.

nf_reset() is used in the following cases:

- when passing packets up the the socket layer, at which point we want to
  release all netfilter references that might keep modules pinned while
  the packet is queued. nf_trace doesn't matter anymore at this point.

- when encapsulating or decapsulating IPsec packets. We want to continue
  tracing these packets after IPsec processing.

- when passing packets through virtual network devices. Only devices on
  that encapsulate in IPv4/v6 matter since otherwise nf_trace is not
  used anymore. Its not entirely clear whether those packets should
  be traced after that, however we've always done that.

- when passing packets through virtual network devices that make the
  packet cross network namespace boundaries. This is the only cases
  where we clearly want to reset nf_trace and is also what the
  original patch intended to fix.

Add a new function nf_reset_trace() and use it in dev_forward_skb() to
fix this properly.

Signed-off-by: Patrick McHardy &lt;kaber@trash.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 124dff01afbdbff251f0385beca84ba1b9adda68 ]

Commit 130549fe ("netfilter: reset nf_trace in nf_reset") added code
to reset nf_trace in nf_reset(). This is wrong and unnecessary.

nf_reset() is used in the following cases:

- when passing packets up the the socket layer, at which point we want to
  release all netfilter references that might keep modules pinned while
  the packet is queued. nf_trace doesn't matter anymore at this point.

- when encapsulating or decapsulating IPsec packets. We want to continue
  tracing these packets after IPsec processing.

- when passing packets through virtual network devices. Only devices on
  that encapsulate in IPv4/v6 matter since otherwise nf_trace is not
  used anymore. Its not entirely clear whether those packets should
  be traced after that, however we've always done that.

- when passing packets through virtual network devices that make the
  packet cross network namespace boundaries. This is the only cases
  where we clearly want to reset nf_trace and is also what the
  original patch intended to fix.

Add a new function nf_reset_trace() and use it in dev_forward_skb() to
fix this properly.

Signed-off-by: Patrick McHardy &lt;kaber@trash.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: count hw_addr syncs so that unsync works properly.</title>
<updated>2013-05-01T15:56:36+00:00</updated>
<author>
<name>Vlad Yasevich</name>
<email>vyasevic@redhat.com</email>
</author>
<published>2013-04-02T21:10:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d569e833b770b21d29147c1ed937ab3882647252'/>
<id>d569e833b770b21d29147c1ed937ab3882647252</id>
<content type='text'>
[ Upstream commit 4543fbefe6e06a9e40d9f2b28d688393a299f079 ]

A few drivers use dev_uc_sync/unsync to synchronize the
address lists from master down to slave/lower devices.  In
some cases (bond/team) a single address list is synched down
to multiple devices.  At the time of unsync, we have a leak
in these lower devices, because "synced" is treated as a
boolean and the address will not be unsynced for anything after
the first device/call.

Treat "synced" as a count (same as refcount) and allow all
unsync calls to work.

Signed-off-by: Vlad Yasevich &lt;vyasevic@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4543fbefe6e06a9e40d9f2b28d688393a299f079 ]

A few drivers use dev_uc_sync/unsync to synchronize the
address lists from master down to slave/lower devices.  In
some cases (bond/team) a single address list is synched down
to multiple devices.  At the time of unsync, we have a leak
in these lower devices, because "synced" is treated as a
boolean and the address will not be unsynced for anything after
the first device/call.

Treat "synced" as a count (same as refcount) and allow all
unsync calls to work.

Signed-off-by: Vlad Yasevich &lt;vyasevic@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vm: add vm_iomap_memory() helper function</title>
<updated>2013-04-26T04:23:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2013-04-16T20:45:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d1a01d18320e37367e23f006f0dfbd74ff32de68'/>
<id>d1a01d18320e37367e23f006f0dfbd74ff32de68</id>
<content type='text'>
commit b4cbb197c7e7a68dbad0d491242e3ca67420c13e upstream.

Various drivers end up replicating the code to mmap() their memory
buffers into user space, and our core memory remapping function may be
very flexible but it is unnecessarily complicated for the common cases
to use.

Our internal VM uses pfn's ("page frame numbers") which simplifies
things for the VM, and allows us to pass physical addresses around in a
denser and more efficient format than passing a "phys_addr_t" around,
and having to shift it up and down by the page size.  But it just means
that drivers end up doing that shifting instead at the interface level.

It also means that drivers end up mucking around with internal VM things
like the vma details (vm_pgoff, vm_start/end) way more than they really
need to.

So this just exports a function to map a certain physical memory range
into user space (using a phys_addr_t based interface that is much more
natural for a driver) and hides all the complexity from the driver.
Some drivers will still end up tweaking the vm_page_prot details for
things like prefetching or cacheability etc, but that's actually
relevant to the driver, rather than caring about what the page offset of
the mapping is into the particular IO memory region.

Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b4cbb197c7e7a68dbad0d491242e3ca67420c13e upstream.

Various drivers end up replicating the code to mmap() their memory
buffers into user space, and our core memory remapping function may be
very flexible but it is unnecessarily complicated for the common cases
to use.

Our internal VM uses pfn's ("page frame numbers") which simplifies
things for the VM, and allows us to pass physical addresses around in a
denser and more efficient format than passing a "phys_addr_t" around,
and having to shift it up and down by the page size.  But it just means
that drivers end up doing that shifting instead at the interface level.

It also means that drivers end up mucking around with internal VM things
like the vma details (vm_pgoff, vm_start/end) way more than they really
need to.

So this just exports a function to map a certain physical memory range
into user space (using a phys_addr_t based interface that is much more
natural for a driver) and hides all the complexity from the driver.
Some drivers will still end up tweaking the vm_page_prot details for
things like prefetching or cacheability etc, but that's actually
relevant to the driver, rather than caring about what the page offset of
the mapping is into the particular IO memory region.

Acked-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: Allow cross page reads and writes from cached translations.</title>
<updated>2013-04-26T04:23:48+00:00</updated>
<author>
<name>Andrew Honig</name>
<email>ahonig@google.com</email>
</author>
<published>2013-03-29T16:35:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d715cdddb8cdf1c17bf1c5ff8fcc9852cd6ba79e'/>
<id>d715cdddb8cdf1c17bf1c5ff8fcc9852cd6ba79e</id>
<content type='text'>
commit 8f964525a121f2ff2df948dac908dcc65be21b5b upstream.

This patch adds support for kvm_gfn_to_hva_cache_init functions for
reads and writes that will cross a page.  If the range falls within
the same memslot, then this will be a fast operation.  If the range
is split between two memslots, then the slower kvm_read_guest and
kvm_write_guest are used.

Tested: Test against kvm_clock unit tests.

Signed-off-by: Andrew Honig &lt;ahonig@google.com&gt;
Signed-off-by: Gleb Natapov &lt;gleb@redhat.com&gt;
Cc: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8f964525a121f2ff2df948dac908dcc65be21b5b upstream.

This patch adds support for kvm_gfn_to_hva_cache_init functions for
reads and writes that will cross a page.  If the range falls within
the same memslot, then this will be a fast operation.  If the range
is split between two memslots, then the slower kvm_read_guest and
kvm_write_guest are used.

Tested: Test against kvm_clock unit tests.

Signed-off-by: Andrew Honig &lt;ahonig@google.com&gt;
Signed-off-by: Gleb Natapov &lt;gleb@redhat.com&gt;
Cc: Ben Hutchings &lt;ben@decadent.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
