linux-kernel - [PATCH 1/2] [for 3.4] drivers/virt: the Freescale hypervisor driver doesn't need to check MSR[GS]

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Date:	Thu, 17 May 2012 14:10:27 -0500
From:	Timur Tabi <timur@...escale.com>
To:	<linuxppc-dev@...ux.freescale.net>,
	Kumar Gala <galak@...nel.crashing.org>,
	Scott Wood <scottwood@...escale.com>,
	Anatolij Gustschin <agust@...x.de>, <geert@...ux-m68k.org>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	<linux-kernel@...r.kernel.org>
Subject: [PATCH 1/2] [for 3.4] drivers/virt: the Freescale hypervisor driver doesn't need to check MSR[GS]

The MSR[GS] bit indicates whether the kernel is running in processor guest
state mode, but such a check is unnecessary.  The driver already checks
for the /hypervisor node and the fsl,hv-version property, so it already
knows that it's running under the Freescale hypervisor.

There is nothing in the driver that inherently requires guest state,
anyway.

This fixes a break that can occur in some randconfig builds.

Signed-off-by: Timur Tabi <timur@...escale.com>
---
 drivers/virt/fsl_hypervisor.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)

diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c
index 4939e0c..d294f67 100644
--- a/drivers/virt/fsl_hypervisor.c
+++ b/drivers/virt/fsl_hypervisor.c
@@ -796,9 +796,6 @@ static int has_fsl_hypervisor(void)
 	struct device_node *node;
 	int ret;
 
-	if (!(mfmsr() & MSR_GS))
-		return 0;
-
 	node = of_find_node_by_path("/hypervisor");
 	if (!node)
 		return 0;
-- 
1.7.3.4


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