<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/arm/include/asm, branch v3.10.41</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>ARM: 7728/1: mm: Use phys_addr_t properly for ioremap functions</title>
<updated>2014-05-06T14:55:27+00:00</updated>
<author>
<name>Laura Abbott</name>
<email>lauraa@codeaurora.org</email>
</author>
<published>2013-05-16T18:40:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6f80251afe07130734c86628cbadff0caba3af27'/>
<id>6f80251afe07130734c86628cbadff0caba3af27</id>
<content type='text'>
commit 9b97173e785a54c5df0aa23d1e1f680f61e36e43 upstream.

Several of the ioremap functions use unsigned long in places
resulting in truncation if physical addresses greater than
4G are passed in. Change the types of the functions and the
callers accordingly.

Cc: Krzysztof Halasa &lt;khc@pm.waw.pl&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Signed-off-by: Laura Abbott &lt;lauraa@codeaurora.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&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 9b97173e785a54c5df0aa23d1e1f680f61e36e43 upstream.

Several of the ioremap functions use unsigned long in places
resulting in truncation if physical addresses greater than
4G are passed in. Change the types of the functions and the
callers accordingly.

Cc: Krzysztof Halasa &lt;khc@pm.waw.pl&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Signed-off-by: Laura Abbott &lt;lauraa@codeaurora.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Wang Nan &lt;wangnan0@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 8027/1: fix do_div() bug in big-endian systems</title>
<updated>2014-05-06T14:55:27+00:00</updated>
<author>
<name>Xiangyu Lu</name>
<email>luxiangyu@huawei.com</email>
</author>
<published>2014-04-15T08:38:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4a91c29ca2e7ae1fa4020e334abfc2174d8c6bdf'/>
<id>4a91c29ca2e7ae1fa4020e334abfc2174d8c6bdf</id>
<content type='text'>
commit 80bb3ef109ff40a7593d9481c17de9bbc4d7c0e2 upstream.

In big-endian systems, "%1" get the most significant part of the value, cause the instruction to get the wrong result.

When viewing ftrace record in big-endian ARM systems, we found that
the timestamp errors:

swapper-0   [001] 1325.970000:   0:120:R ==&gt; [001]    16:120:R events/1
events/1-16 [001] 1325.970000:   16:120:S ==&gt; [001]    0:120:R swapper
swapper-0   [000] 1325.1000000:  0:120:R   + [000]    15:120:R events/0
swapper-0   [000] 1325.1000000:  0:120:R ==&gt; [000]    15:120:R events/0
swapper-0   [000] 1326.030000:   0:120:R   + [000]  1150:120:R sshd
swapper-0   [000] 1326.030000:   0:120:R ==&gt; [000]  1150:120:R sshd

When viewed ftrace records, it will call the do_div(n, base) function, which achieved arch/arm/include/asm/div64.h in. When n = 10000000, base = 1000000, in do_div(n, base) will execute "umull %Q0, %R0, %1, %Q2".

Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Alex Wu &lt;wuquanming@huawei.com&gt;
Signed-off-by: Xiangyu Lu &lt;luxiangyu@huawei.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.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 80bb3ef109ff40a7593d9481c17de9bbc4d7c0e2 upstream.

In big-endian systems, "%1" get the most significant part of the value, cause the instruction to get the wrong result.

When viewing ftrace record in big-endian ARM systems, we found that
the timestamp errors:

swapper-0   [001] 1325.970000:   0:120:R ==&gt; [001]    16:120:R events/1
events/1-16 [001] 1325.970000:   16:120:S ==&gt; [001]    0:120:R swapper
swapper-0   [000] 1325.1000000:  0:120:R   + [000]    15:120:R events/0
swapper-0   [000] 1325.1000000:  0:120:R ==&gt; [000]    15:120:R events/0
swapper-0   [000] 1326.030000:   0:120:R   + [000]  1150:120:R sshd
swapper-0   [000] 1326.030000:   0:120:R ==&gt; [000]  1150:120:R sshd

When viewed ftrace records, it will call the do_div(n, base) function, which achieved arch/arm/include/asm/div64.h in. When n = 10000000, base = 1000000, in do_div(n, base) will execute "umull %Q0, %R0, %1, %Q2".

Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Alex Wu &lt;wuquanming@huawei.com&gt;
Signed-off-by: Xiangyu Lu &lt;luxiangyu@huawei.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 8007/1: Remove extraneous kcmp syscall ignore</title>
<updated>2014-05-06T14:55:26+00:00</updated>
<author>
<name>Christopher Covington</name>
<email>cov@codeaurora.org</email>
</author>
<published>2014-03-19T17:12:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ec474f3aef984135bbc568ddc903083a5170e308'/>
<id>ec474f3aef984135bbc568ddc903083a5170e308</id>
<content type='text'>
commit 95c52fe063351192e0f4ffb70ef9bac1aa26f5a4 upstream.

The kcmp system call was ported to ARM in
commit 3f7d1fe108dbaefd0c57a41753fc2c90b395f458
"ARM: 7665/1: Wire up kcmp syscall".

Fixes: 3f7d1fe108db ("ARM: 7665/1: Wire up kcmp syscall")
Signed-off-by: Christopher Covington &lt;cov@codeaurora.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.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 95c52fe063351192e0f4ffb70ef9bac1aa26f5a4 upstream.

The kcmp system call was ported to ARM in
commit 3f7d1fe108dbaefd0c57a41753fc2c90b395f458
"ARM: 7665/1: Wire up kcmp syscall".

Fixes: 3f7d1fe108db ("ARM: 7665/1: Wire up kcmp syscall")
Signed-off-by: Christopher Covington &lt;cov@codeaurora.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7954/1: mm: remove remaining domain support from ARMv6</title>
<updated>2014-05-06T14:55:26+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2014-02-07T18:12:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d895644c13bab61f17bc65c86cd2b2c80c44f930'/>
<id>d895644c13bab61f17bc65c86cd2b2c80c44f930</id>
<content type='text'>
commit b6ccb9803e90c16b212cf4ed62913a7591e79a39 upstream.

CPU_32v6 currently selects CPU_USE_DOMAINS if CPU_V6 and MMU. This is
because ARM 1136 r0pX CPUs lack the v6k extensions, and therefore do
not have hardware thread registers. The lack of these registers requires
the kernel to update the vectors page at each context switch in order to
write a new TLS pointer. This write must be done via the userspace
mapping, since aliasing caches can lead to expensive flushing when using
kmap. Finally, this requires the vectors page to be mapped r/w for
kernel and r/o for user, which has implications for things like put_user
which must trigger CoW appropriately when targetting user pages.

The upshot of all this is that a v6/v7 kernel makes use of domains to
segregate kernel and user memory accesses. This has the nasty
side-effect of making device mappings executable, which has been
observed to cause subtle bugs on recent cores (e.g. Cortex-A15
performing a speculative instruction fetch from the GIC and acking an
interrupt in the process).

This patch solves this problem by removing the remaining domain support
from ARMv6. A new memory type is added specifically for the vectors page
which allows that page (and only that page) to be mapped as user r/o,
kernel r/w. All other user r/o pages are mapped also as kernel r/o.
Patch co-developed with Russell King.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.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 b6ccb9803e90c16b212cf4ed62913a7591e79a39 upstream.

CPU_32v6 currently selects CPU_USE_DOMAINS if CPU_V6 and MMU. This is
because ARM 1136 r0pX CPUs lack the v6k extensions, and therefore do
not have hardware thread registers. The lack of these registers requires
the kernel to update the vectors page at each context switch in order to
write a new TLS pointer. This write must be done via the userspace
mapping, since aliasing caches can lead to expensive flushing when using
kmap. Finally, this requires the vectors page to be mapped r/w for
kernel and r/o for user, which has implications for things like put_user
which must trigger CoW appropriately when targetting user pages.

The upshot of all this is that a v6/v7 kernel makes use of domains to
segregate kernel and user memory accesses. This has the nasty
side-effect of making device mappings executable, which has been
observed to cause subtle bugs on recent cores (e.g. Cortex-A15
performing a speculative instruction fetch from the GIC and acking an
interrupt in the process).

This patch solves this problem by removing the remaining domain support
from ARMv6. A new memory type is added specifically for the vectors page
which allows that page (and only that page) to be mapped as user r/o,
kernel r/w. All other user r/o pages are mapped also as kernel r/o.
Patch co-developed with Russell King.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: move outer_cache declaration out of ifdef</title>
<updated>2014-03-31T16:58:13+00:00</updated>
<author>
<name>Rob Herring</name>
<email>rob.herring@calxeda.com</email>
</author>
<published>2013-08-18T01:12:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c46696c9e2235a4f00aa424509fd3c12ebcfc475'/>
<id>c46696c9e2235a4f00aa424509fd3c12ebcfc475</id>
<content type='text'>
commit 0b53c11d533a8f6688d73fad0baf67dd08ec1b90 upstream.

Move the outer_cache declaration of the CONFIG_OUTER_CACHE ifdef so that
outer_cache can be used inside IS_ENABLED condition.

Signed-off-by: Rob Herring &lt;rob.herring@calxeda.com&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Signed-off-by: Ian Campbell &lt;ian.campbell@citrix.com&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 0b53c11d533a8f6688d73fad0baf67dd08ec1b90 upstream.

Move the outer_cache declaration of the CONFIG_OUTER_CACHE ifdef so that
outer_cache can be used inside IS_ENABLED condition.

Signed-off-by: Rob Herring &lt;rob.herring@calxeda.com&gt;
Cc: Russell King &lt;linux@arm.linux.org.uk&gt;
Signed-off-by: Ian Campbell &lt;ian.campbell@citrix.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7811/1: locks: use early clobber in arch_spin_trylock</title>
<updated>2014-03-24T04:38:13+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2013-08-12T17:03:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9400319cc170bec3ff02f0adcb978552682725af'/>
<id>9400319cc170bec3ff02f0adcb978552682725af</id>
<content type='text'>
commit afa31d8eb86fc2f25083e675d57ac8173a98f999 upstream.

The res variable is written before we've finished with the input
operands (namely the lock address), so ensure that we mark it as `early
clobber' to avoid unintended register sharing.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Wang Weidong &lt;wangweidong1@huawei.com&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 afa31d8eb86fc2f25083e675d57ac8173a98f999 upstream.

The res variable is written before we've finished with the input
operands (namely the lock address), so ensure that we mark it as `early
clobber' to avoid unintended register sharing.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Wang Weidong &lt;wangweidong1@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7812/1: rwlocks: retry trylock operation if strex fails on free lock</title>
<updated>2014-03-07T05:30:13+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2013-08-12T17:04:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fed783a535fe9cf3068977562235cf334fbff0b3'/>
<id>fed783a535fe9cf3068977562235cf334fbff0b3</id>
<content type='text'>
commit 00efaa0250939dc148e2d3104fb3c18395d24a2d upstream.

Commit 15e7e5c1ebf5 ("ARM: 7749/1: spinlock: retry trylock operation if
strex fails on free lock") modifying our arch_spin_trylock to retry the
acquisition if the lock appeared uncontended, but the strex failed.

This patch does the same for rwlocks, which were missed by the original
patch.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Li Zefan &lt;lizefan@huawei.com&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 00efaa0250939dc148e2d3104fb3c18395d24a2d upstream.

Commit 15e7e5c1ebf5 ("ARM: 7749/1: spinlock: retry trylock operation if
strex fails on free lock") modifying our arch_spin_trylock to retry the
acquisition if the lock appeared uncontended, but the strex failed.

This patch does the same for rwlocks, which were missed by the original
patch.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Li Zefan &lt;lizefan@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7749/1: spinlock: retry trylock operation if strex fails on free lock</title>
<updated>2014-03-07T05:30:13+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2013-06-05T10:27:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f411a4439b68149518898379d7d537a32becb381'/>
<id>f411a4439b68149518898379d7d537a32becb381</id>
<content type='text'>
commit 15e7e5c1ebf556cd620c9b091e121091ac760f6d upstream.

An exclusive store instruction may fail for reasons other than lock
contention (e.g. a cache eviction during the critical section) so, in
line with other architectures using similar exclusive instructions
(alpha, mips, powerpc), retry the trylock operation if the lock appears
to be free but the strex reported failure.

Reported-by: Tony Thompson &lt;anthony.thompson@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Li Zefan &lt;lizefan@huawei.com&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 15e7e5c1ebf556cd620c9b091e121091ac760f6d upstream.

An exclusive store instruction may fail for reasons other than lock
contention (e.g. a cache eviction during the critical section) so, in
line with other architectures using similar exclusive instructions
(alpha, mips, powerpc), retry the trylock operation if the lock appears
to be free but the strex reported failure.

Reported-by: Tony Thompson &lt;anthony.thompson@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Li Zefan &lt;lizefan@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7957/1: add DSB after icache flush in __flush_icache_all()</title>
<updated>2014-03-07T05:30:01+00:00</updated>
<author>
<name>Vinayak Kale</name>
<email>vkale@apm.com</email>
</author>
<published>2014-02-12T06:30:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c943f5f92411ccb977e3272615309d3877d435f5'/>
<id>c943f5f92411ccb977e3272615309d3877d435f5</id>
<content type='text'>
commit 39544ac9df20f73e49fc6b9ac19ff533388c82c0 upstream.

Add DSB after icache flush to complete the cache maintenance operation.

Signed-off-by: Vinayak Kale &lt;vkale@apm.com&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.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 39544ac9df20f73e49fc6b9ac19ff533388c82c0 upstream.

Add DSB after icache flush to complete the cache maintenance operation.

Signed-off-by: Vinayak Kale &lt;vkale@apm.com&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>clocksource: arch_timer: use virtual counters</title>
<updated>2014-01-09T20:24:26+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2013-01-30T17:51:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=714c21cb90951905b269870087a99c37f3a7af0c'/>
<id>714c21cb90951905b269870087a99c37f3a7af0c</id>
<content type='text'>
commit 0d651e4e65e96989f72236bf83bd4c6e55eb6ce4 upstream.

Switching between reading the virtual or physical counters is
problematic, as some core code wants a view of time before we're fully
set up. Using a function pointer and switching the source after the
first read can make time appear to go backwards, and having a check in
the read function is an unfortunate block on what we want to be a fast
path.

Instead, this patch makes us always use the virtual counters. If we're a
guest, or don't have hyp mode, we'll use the virtual timers, and as such
don't care about CNTVOFF as long as it doesn't change in such a way as
to make time appear to travel backwards. As the guest will use the
virtual timers, a (potential) KVM host must use the physical timers
(which can wake up the host even if they fire while a guest is
executing), and hence a host must have CNTVOFF set to zero so as to have
a consistent view of time between the physical timers and virtual
counters.

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Acked-by: Santosh Shilimkar &lt;santosh.shilimkar@ti.com&gt;
Cc: Rob Herring &lt;rob.herring@calxeda.com&gt;
Cc: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
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commit 0d651e4e65e96989f72236bf83bd4c6e55eb6ce4 upstream.

Switching between reading the virtual or physical counters is
problematic, as some core code wants a view of time before we're fully
set up. Using a function pointer and switching the source after the
first read can make time appear to go backwards, and having a check in
the read function is an unfortunate block on what we want to be a fast
path.

Instead, this patch makes us always use the virtual counters. If we're a
guest, or don't have hyp mode, we'll use the virtual timers, and as such
don't care about CNTVOFF as long as it doesn't change in such a way as
to make time appear to travel backwards. As the guest will use the
virtual timers, a (potential) KVM host must use the physical timers
(which can wake up the host even if they fire while a guest is
executing), and hence a host must have CNTVOFF set to zero so as to have
a consistent view of time between the physical timers and virtual
counters.

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Acked-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Acked-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Acked-by: Santosh Shilimkar &lt;santosh.shilimkar@ti.com&gt;
Cc: Rob Herring &lt;rob.herring@calxeda.com&gt;
Cc: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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