2013-02-26 (?), 11:29 -0800, Kevin Hilman:

Frederic Weisbecker [off-list ref] writes:

quoted

On Wed, Feb 20, 2013 at 11:41:38AM -0800, Kevin Hilman wrote:

quoted

So that it can build on !KVM systems too.

Signed-off-by: Kevin Hilman <redacted>
---
 kernel/context_tracking.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c
index 74f68f4..6fe96b1 100644
--- a/kernel/context_tracking.c
+++ b/kernel/context_tracking.c

@@ -1,5 +1,7 @@
 #include <linux/context_tracking.h>
+#ifdef CONFIG_KVM
 #include <linux/kvm_host.h>
+#endif

The header should take care of the off-case, no need to ifdef its inclusion.

In their current form, the headers will not build on platforms without
KVM support.  For example, these platforms (like ARM) don't even have
<asm/kvm.h> or <asm/kvm_host.h>.

quoted

quoted

 #include <linux/rcupdate.h>
 #include <linux/sched.h>
 #include <linux/hardirq.h>

@@ -62,6 +64,7 @@ void user_exit(void)
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_KVM
 void guest_enter(void)
 {
 	if (vtime_accounting_enabled())

@@ -79,6 +82,7 @@ void guest_exit(void)
 		__guest_exit();
 }
 EXPORT_SYMBOL_GPL(guest_exit);
+#endif

Kvm might be built as a module so we can't actually do this unfortunately.

Ah, right.  How bout using 

#if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)

for both conditionals above?  Updated patch below.

This is what IS_ENABLED(CONFIG_KVM) is for.

Thanks,
Namhyung