[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1424374196-4954-1-git-send-email-rabin@rab.in>
Date: Thu, 19 Feb 2015 20:29:51 +0100
From: Rabin Vincent <rabin@....in>
To: jesper.nilsson@...s.com
Cc: linux-cris-kernel@...s.com, linux-kernel@...r.kernel.org,
Rabin Vincent <rabin@....in>
Subject: [PATCH 1/6] CRISv32: don't enable irqs in INIT_THREAD
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@....in>
---
arch/cris/include/arch-v32/arch/processor.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/cris/include/arch-v32/arch/processor.h b/arch/cris/include/arch-v32/arch/processor.h
index a024b7d..5687592 100644
--- a/arch/cris/include/arch-v32/arch/processor.h
+++ b/arch/cris/include/arch-v32/arch/processor.h
@@ -25,8 +25,7 @@ struct thread_struct {
*/
#define TASK_SIZE (0xB0000000UL)
-/* CCS I=1, enable interrupts. */
-#define INIT_THREAD { 0, 0, (1 << I_CCS_BITNR) }
+#define INIT_THREAD { }
#define KSTK_EIP(tsk) \
({ \
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists