+ ipmi-handle-run_to_completion-properly-in-deliver_recv_msg.patch added to -mm tree

+ ipmi-handle-run_to_completion-properly-in-deliver_recv_msg.patch added to -mm tree

[akpm]

The patch titled
     ipmi: handle run_to_completion properly in deliver_recv_msg()
has been added to the -mm tree.  Its filename is
     ipmi-handle-run_to_completion-properly-in-deliver_recv_msg.patch

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------------------------------------------------------
Subject: ipmi: handle run_to_completion properly in deliver_recv_msg()
From: Jiri Kosina <jkosina@suse.cz>

If run_to_completion flag is set, it means that we are running in a
single-threaded mode, and thus no locks are held.

This fixes a deadlock when IPMI notifier is being called during panic.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/char/ipmi/ipmi_si_intf.c |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff -puN drivers/char/ipmi/ipmi_si_intf.c~ipmi-handle-run_to_completion-properly-in-deliver_recv_msg drivers/char/ipmi/ipmi_si_intf.c
--- a/drivers/char/ipmi/ipmi_si_intf.c~ipmi-handle-run_to_completion-properly-in-deliver_recv_msg
+++ a/drivers/char/ipmi/ipmi_si_intf.c
@@ -323,9 +323,14 @@ static void deliver_recv_msg(struct smi_
 {
 	/* Deliver the message to the upper layer with the lock
 	   released. */
-	spin_unlock(&(smi_info->si_lock));
-	ipmi_smi_msg_received(smi_info->intf, msg);
-	spin_lock(&(smi_info->si_lock));
+
+	if (smi_info->run_to_completion) {
+		ipmi_smi_msg_received(smi_info->intf, msg);
+	} else {
+		spin_unlock(&(smi_info->si_lock));
+		ipmi_smi_msg_received(smi_info->intf, msg);
+		spin_lock(&(smi_info->si_lock));
+	}
 }
 
 static void return_hosed_msg(struct smi_info *smi_info, int cCode)
_

Patches currently in -mm which might be from jkosina@suse.cz are

origin.patch
linux-next.patch
acpi-video-fix-acpi_backlight=video.patch
ipmi-handle-run_to_completion-properly-in-deliver_recv_msg.patch