[PATCH] shpchp - Fix incorrect return value of interrupt handler

Current SHPCHP driver has a bug in its interrupt handler which cause
"IRQ #: nobody cared" oops. This problem can be reproduced easily by
the following operation.

    # cd /sys/bus/pci/slots/<slot#>
    # while true; do echo 1 > attention ; done &

The reason is that when command complete interrupt is raised, current
SHPCHP driver's interrupt handler returns IRQ_NONE regardless of if
the interrupt is handled or not.

This patch fixes this issue.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 8 deletions

diff --git a/drivers/pci/hotplug/shpchp_hpc.c b/drivers/pci/hotplug/shpchp_hpc.c
index 1a6b5448f81d..943ed2b4dabe 100644
--- a/drivers/pci/hotplug/shpchp_hpc.c
+++ b/drivers/pci/hotplug/shpchp_hpc.c
@@ -1109,14 +1109,8 @@ static irqreturn_t shpc_isr(int IRQ, void *dev_id, struct pt_regs *regs)
                 wake_up_interruptible(&ctrl->queue);
         }
 
-        if ((intr_loc = (intr_loc >> 1)) == 0) {
-                /* Unmask Global Interrupt Mask */
-                temp_dword = readl(php_ctlr->creg + SERR_INTR_ENABLE);
-                temp_dword &= 0xfffffffe;
-                writel(temp_dword, php_ctlr->creg + SERR_INTR_ENABLE);
-
-                return IRQ_NONE;
-        }
+        if ((intr_loc = (intr_loc >> 1)) == 0)
+                goto out;
 
         for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) { 
         /* To find out which slot has interrupt pending */
@@ -1146,6 +1140,7 @@ static irqreturn_t shpc_isr(int IRQ, void *dev_id, struct pt_regs *regs)
                         dbg("%s: intr_loc2 = %x\n",__FUNCTION__, intr_loc2); 
                 }
         }
+ out:
         if (!shpchp_poll_mode) {
                 /* Unmask Global Interrupt Mask */
                 temp_dword = readl(php_ctlr->creg + SERR_INTR_ENABLE);