From: Steve Best <sbest@redhat.com>
Date: Tue, 16 Nov 2010 15:17:02 -0500
Subject: [infiniband] ehea: use shca_list_lock spinlock
Message-id: <20101116151156.17393.78517.sendpatchset@squad5-lp1.lab.bos.redhat.com>
Patchwork-id: 29455
O-Subject: [PATCH RHEL5.6 BZ613797] IB/ehea: change the spinlock that's being
	locked to shca_list_lock
Bugzilla: 613797
RH-Acked-by: David Howells <dhowells@redhat.com>
RH-Acked-by: David S. Miller <davem@redhat.com>
RH-Acked-by: Doug Ledford <dledford@redhat.com>

RHBZ#:
------
https://bugzilla.redhat.com/show_bug.cgi?id=613797

Description:
------------
For RH-5.5 a fixed was done for #bz 561952 in the interruption code of ehca.
That the fix is not completed. In the patch we introduce the shca_list_lock
which is used during destroy of an event queue instead of the eq->spinlock.
This patch uses the new scha_list_lock.

RHEL Version Found:
-------------------
RHEL 5.6

kABI Status:
------------
No symbols were harmed.

Brew:
-----
http://brewweb.devel.redhat.com/brew/taskinfo?taskID=2895033

Upstream Status:
----------------
This patch does not have an upstream equivalent per se. The back port
for bz 561952, forgot a small (but important) detail of the patch.
This fix adds that detail.

The upstream equivalent of the complete fix (including this detail) is commit
9420269428b3dc80c98e52beac60a3976fbef7d2

The mistake is obvious when looking at the attached patch -- the spinlock that's
being locked needed to be shca_list_lock. The upstream patch does it right.

Test Status:
------------
Joachim Fenkes helped me test this patch.

===============================================================
Steve Best
IBM on-site partner

Proposed Patch:

Signed-off-by: Jarod Wilson <jarod@redhat.com>

diff --git a/drivers/infiniband/hw/ehca/ehca_eq.c b/drivers/infiniband/hw/ehca/ehca_eq.c
index f782681..73de94d 100644
--- a/drivers/infiniband/hw/ehca/ehca_eq.c
+++ b/drivers/infiniband/hw/ehca/ehca_eq.c
@@ -171,9 +171,9 @@ int ehca_destroy_eq(struct ehca_shca *shca, struct ehca_eq *eq)
 
 	ibmebus_free_irq(NULL, eq->ist, (void *)shca);
 
-	spin_lock_irqsave(&eq->spinlock, flags);
+	spin_lock_irqsave(&shca_list_lock, flags);
 	eq->is_initialized = 0;
-	spin_unlock_irqrestore(&eq->spinlock, flags);
+	spin_unlock_irqrestore(&shca_list_lock, flags);
 	
 	tasklet_kill(&eq->interrupt_task);