This is a note to let you know that I've just added the patch titled

ipmi/watchdog: fix wdog hang on panic waiting for ipmi response

to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ipmi-watchdog-fix-wdog-hang-on-panic-waiting-for-ipmi-response.patch and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Thu Mar 22 15:16:04 CET 2018

From: Robert Lippert roblip@gmail.com Date: Thu, 20 Apr 2017 16:49:47 -0700 Subject: ipmi/watchdog: fix wdog hang on panic waiting for ipmi response

From: Robert Lippert roblip@gmail.com

[ Upstream commit 2c1175c2e8e5487233cabde358a19577562ac83e ]

Commit c49c097610fe ("ipmi: Don't call receive handler in the panic context") means that the panic_recv_free is not called during a panic and the atomic count does not drop to 0.

Fix this by only expecting one decrement of the atomic variable which comes from panic_smi_free.

Signed-off-by: Robert Lippert rlippert@google.com Signed-off-by: Corey Minyard cminyard@mvista.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/char/ipmi/ipmi_watchdog.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/char/ipmi/ipmi_watchdog.c +++ b/drivers/char/ipmi/ipmi_watchdog.c @@ -509,7 +509,7 @@ static void panic_halt_ipmi_heartbeat(vo msg.cmd = IPMI_WDOG_RESET_TIMER; msg.data = NULL; msg.data_len = 0; - atomic_add(2, &panic_done_count); + atomic_add(1, &panic_done_count); rv = ipmi_request_supply_msgs(watchdog_user, (struct ipmi_addr *) &addr, 0, @@ -519,7 +519,7 @@ static void panic_halt_ipmi_heartbeat(vo &panic_halt_heartbeat_recv_msg, 1); if (rv) - atomic_sub(2, &panic_done_count); + atomic_sub(1, &panic_done_count); }

static struct ipmi_smi_msg panic_halt_smi_msg = { @@ -543,12 +543,12 @@ static void panic_halt_ipmi_set_timeout( /* Wait for the messages to be free. */ while (atomic_read(&panic_done_count) != 0) ipmi_poll_interface(watchdog_user); - atomic_add(2, &panic_done_count); + atomic_add(1, &panic_done_count); rv = i_ipmi_set_timeout(&panic_halt_smi_msg, &panic_halt_recv_msg, &send_heartbeat_now); if (rv) { - atomic_sub(2, &panic_done_count); + atomic_sub(1, &panic_done_count); printk(KERN_WARNING PFX "Unable to extend the watchdog timeout."); } else {

Patches currently in stable-queue which might be from roblip@gmail.com are

queue-3.18/ipmi-watchdog-fix-wdog-hang-on-panic-waiting-for-ipmi-response.patch