[PATCH 011/222] x86: hpet: Fix masking of MSI interrupts

[Herton Ronaldo Krzesinski]

3.5.7.3 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jan Beulich <JBeulich at suse.com>

commit 6acf5a8c931da9d26c8dd77d784daaf07fa2bff0 upstream.

HPET_TN_FSB is not a proper mask bit; it merely toggles between MSI and
legacy interrupt delivery. The proper mask bit is HPET_TN_ENABLE, so
use both bits when (un)masking the interrupt.

Signed-off-by: Jan Beulich <jbeulich at suse.com>
Link: http://lkml.kernel.org/r/5093E09002000078000A60E6@nat28.tlf.novell.com
Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 arch/x86/kernel/hpet.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index 1460a5d..e28670f 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -434,7 +434,7 @@ void hpet_msi_unmask(struct irq_data *data)
 
 	/* unmask it */
 	cfg = hpet_readl(HPET_Tn_CFG(hdev->num));
-	cfg |= HPET_TN_FSB;
+	cfg |= HPET_TN_ENABLE | HPET_TN_FSB;
 	hpet_writel(cfg, HPET_Tn_CFG(hdev->num));
 }
 
@@ -445,7 +445,7 @@ void hpet_msi_mask(struct irq_data *data)
 
 	/* mask it */
 	cfg = hpet_readl(HPET_Tn_CFG(hdev->num));
-	cfg &= ~HPET_TN_FSB;
+	cfg &= ~(HPET_TN_ENABLE | HPET_TN_FSB);
 	hpet_writel(cfg, HPET_Tn_CFG(hdev->num));
 }
 
-- 
1.7.9.5