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

    MIPS: Fix kernel lockup or crash after CPU offline/online

to the 3.18-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mips-fix-kernel-lockup-or-crash-after-cpu-offline-online.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 <[email protected]> know about it.


>From c7754e75100ed5e3068ac5085747f2bfc386c8d6 Mon Sep 17 00:00:00 2001
From: Hemmo Nieminen <[email protected]>
Date: Thu, 15 Jan 2015 23:01:59 +0200
Subject: MIPS: Fix kernel lockup or crash after CPU offline/online

From: Hemmo Nieminen <[email protected]>

commit c7754e75100ed5e3068ac5085747f2bfc386c8d6 upstream.

As printk() invocation can cause e.g. a TLB miss, printk() cannot be
called before the exception handlers have been properly initialized.
This can happen e.g. when netconsole has been loaded as a kernel module
and the TLB table has been cleared when a CPU was offline.

Call cpu_report() in start_secondary() only after the exception handlers
have been initialized to fix this.

Without the patch the kernel will randomly either lockup or crash
after a CPU is onlined and the console driver is a module.

Signed-off-by: Hemmo Nieminen <[email protected]>
Signed-off-by: Aaro Koskinen <[email protected]>
Cc: David Daney <[email protected]>
Cc: [email protected]
Cc: [email protected]
Patchwork: https://patchwork.linux-mips.org/patch/8953/
Signed-off-by: Ralf Baechle <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/mips/kernel/smp.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -123,10 +123,10 @@ asmlinkage void start_secondary(void)
        unsigned int cpu;
 
        cpu_probe();
-       cpu_report();
        per_cpu_trap_init(false);
        mips_clockevent_init();
        mp_ops->init_secondary();
+       cpu_report();
 
        /*
         * XXX parity protection should be folded in here when it's converted


Patches currently in stable-queue which might be from [email protected] are

queue-3.18/mips-fix-kernel-lockup-or-crash-after-cpu-offline-online.patch
queue-3.18/mips-octeon-fix-kernel-crash-when-offlining-a-cpu.patch
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