Re: [PATCH 1/6] CRISv32: don't enable irqs in INIT_THREAD

[Jesper Nilsson]

On Thu, Feb 19, 2015 at 08:29:51PM +0100, Rabin Vincent wrote:
> INIT_THREAD enables interrupts in the thread_struct's saved flags.  This
> means that interrupts get enabled in the middle of context_switch()
> while switching to new tasks that get forked off the init task during
> boot.  Don't do this.
> 
> Fixes the following splat on boot with spinlock debugging on:
> 
>   BUG: spinlock cpu recursion on CPU#0, swapper/2
>    lock: runqueues+0x0/0x47c, .magic: dead4ead, .owner: swapper/0,
>   .owner_cpu: 0
>   CPU: 0 PID: 2 Comm: swapper Not tainted 3.19.0-08796-ga747b55 #285
> 
>   Call Trace:
>   [<c0032b80>] spin_bug+0x2a/0x36
>   [<c0032c98>] do_raw_spin_lock+0xa2/0x126
>   [<c01964b0>] _raw_spin_lock+0x20/0x2a
>   [<c00286c8>] scheduler_tick+0x22/0x76
>   [<c003db2c>] update_process_times+0x5e/0x72
>   [<c0007a94>] timer_interrupt+0x4e/0x6a
>   [<c00378d6>] handle_irq_event_percpu+0x54/0xf2
>   [<c00379c4>] handle_irq_event+0x50/0x74
>   [<c003988e>] handle_simple_irq+0x6c/0xbe
>   [<c0037270>] generic_handle_irq+0x2a/0x36
>   [<c0004c40>] do_IRQ+0x38/0x84
>   [<c000662e>] crisv32_do_IRQ+0x54/0x60
>   [<c0006204>] IRQ0x4b_interrupt+0x34/0x3c
>   [<c0192baa>] __schedule+0x24a/0x532
>   [<c00056b4>] ret_from_kernel_thread+0x0/0x14
> 
> Signed-off-by: Rabin Vincent <rabin@xxxxxx>

Looks good, adding to the CRIS-tree.

/^JN - Jesper Nilsson
-- 
               Jesper Nilsson -- jesper.nilsson@xxxxxxxx
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