[PATCH] xen: Make VPMU init message look less scary

From: Juergen Gross
Date: Mon Aug 01 2016 - 07:41:56 EST


The default for the Xen hypervisor is to not enable VPMU in order to
avoid security issues. In this case the Linux kernel will issue the
message "Could not initialize VPMU for cpu 0, error -95" which looks
more like an error than a normal state.

Change the message to something less scary in case the hypervisor
returns EOPNOTSUPP when trying to activate VPMU.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
arch/x86/xen/pmu.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/x86/xen/pmu.c b/arch/x86/xen/pmu.c
index 32bdc2c..e9d66fa 100644
--- a/arch/x86/xen/pmu.c
+++ b/arch/x86/xen/pmu.c
@@ -547,8 +547,11 @@ void xen_pmu_init(int cpu)
return;

fail:
- pr_info_once("Could not initialize VPMU for cpu %d, error %d\n",
- cpu, err);
+ if (err == -EOPNOTSUPP)
+ pr_info_once("VPMU usage disabled due to Xen settings\n");
+ else
+ pr_info_once("Could not initialize VPMU for cpu %d, error %d\n",
+ cpu, err);
free_pages((unsigned long)xenpmu_data, 0);
}

--
2.6.6