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Subject[patch] sgi-xp: nested calls to spin_lock_irqsave()
The code here has a nested spin_lock_irqsave().  It's not needed since
IRQs are already disabled and it causes a problem because it means that
IRQs won't be enabled again at the end. The second call to
spin_lock_irqsave() will overwrite the value of irq_flags and we can't
restore the proper settings.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
This is a static checker fix. It's possible that no one hits this bug
in real life if the function is always called with IRQs disabled.

diff --git a/drivers/misc/sgi-xp/xpc_uv.c b/drivers/misc/sgi-xp/xpc_uv.c
index 17bbacb..87b251a 100644
--- a/drivers/misc/sgi-xp/xpc_uv.c
+++ b/drivers/misc/sgi-xp/xpc_uv.c
@@ -452,9 +452,9 @@ xpc_handle_activate_mq_msg_uv(struct xpc_partition *part,

if (msg->activate_gru_mq_desc_gpa !=
part_uv->activate_gru_mq_desc_gpa) {
- spin_lock_irqsave(&part_uv->flags_lock, irq_flags);
+ spin_lock(&part_uv->flags_lock);
part_uv->flags &= ~XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV;
- spin_unlock_irqrestore(&part_uv->flags_lock, irq_flags);
+ spin_unlock(&part_uv->flags_lock);
part_uv->activate_gru_mq_desc_gpa =
msg->activate_gru_mq_desc_gpa;
}

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