diff options
authorFlorian Fainelli <f.fainelli@gmail.com>2016-08-24 11:01:20 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-09-30 10:18:36 +0200
commita3fb2b3bd4f095327a98c484260fb63851d3bb14 (patch)
parentc03c024fd36db587cb0797408d5c64adf096f678 (diff)
net: dsa: bcm_sf2: Fix race condition while unmasking interrupts
[ Upstream commit 4f101c47791cdcb831b3ef1f831b1cc51e4fe03c ] We kept shadow copies of which interrupt sources we have enabled and disabled, but due to an order bug in how intrl2_mask_clear was defined, we could run into the following scenario: CPU0 CPU1 intrl2_1_mask_clear(..) sets INTRL2_CPU_MASK_CLEAR bcm_sf2_switch_1_isr read INTRL2_CPU_STATUS and masks with stale irq1_mask value updates irq1_mask value Which would make us loop again and again trying to process and interrupt we are not clearing since our copy of whether it was enabled before still indicates it was not. Fix this by updating the shadow copy first, and then unasking at the HW level. Fixes: 246d7f773c13 ("net: dsa: add Broadcom SF2 switch driver") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/dsa/bcm_sf2.h b/drivers/net/dsa/bcm_sf2.h
index 6bba1c98d764..c7994e372284 100644
--- a/drivers/net/dsa/bcm_sf2.h
+++ b/drivers/net/dsa/bcm_sf2.h
@@ -187,8 +187,8 @@ static inline void name##_writeq(struct bcm_sf2_priv *priv, u64 val, \
static inline void intrl2_##which##_mask_clear(struct bcm_sf2_priv *priv, \
u32 mask) \
{ \
- intrl2_##which##_writel(priv, mask, INTRL2_CPU_MASK_CLEAR); \
priv->irq##which##_mask &= ~(mask); \
+ intrl2_##which##_writel(priv, mask, INTRL2_CPU_MASK_CLEAR); \
} \
static inline void intrl2_##which##_mask_set(struct bcm_sf2_priv *priv, \
u32 mask) \