Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758426Ab2J2KAh (ORCPT ); Mon, 29 Oct 2012 06:00:37 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:53678 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758399Ab2J2KAe (ORCPT ); Mon, 29 Oct 2012 06:00:34 -0400 X-AuditID: cbfee61a-b7fa66d0000004cf-14-508e53be75eb From: Bartlomiej Zolnierkiewicz To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org Cc: jassisinghbrar@gmail.com, vinod.koul@intel.com, kgene.kim@samsung.com, rob.herring@calxeda.com, dinguyen@altera.com, pawel.moll@arm.com, t.figa@samsung.com, kyungmin.park@samsung.com, Bartlomiej Zolnierkiewicz , Vinod Koul Subject: [PATCH 1/4] DMA: PL330: fix locking in pl330_free_chan_resources() Date: Mon, 29 Oct 2012 10:59:53 +0100 Message-id: <1351504796-24788-2-git-send-email-b.zolnierkie@samsung.com> X-Mailer: git-send-email 1.7.10 In-reply-to: <1351504796-24788-1-git-send-email-b.zolnierkie@samsung.com> References: <1351504796-24788-1-git-send-email-b.zolnierkie@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrOJMWRmVeSWpSXmKPExsVy+t9jQd19wX0BBm8f81hc3jWHzWLG+X1M DkwenzfJBTBGcdmkpOZklqUW6dslcGXs38tbsFOm4vfBx2wNjDMkuxg5OSQETCT+rT3CBmGL SVy4tx7I5uIQEpjOKLHpwXomCKeLSWLZ5lWsIFVsAlYSE9tXMYLYIgLZEj++TWYBKWIWWMgk 8WrPWXaQhLCAt8TK7cfAbBYBVYkHLV1gK3gFPCRuTjjDCrFOXuLp/T6wOKeAp8TpiauYQWwh oJp/n/azT2DkXcDIsIpRNLUguaA4KT3XUK84Mbe4NC9dLzk/dxMj2PvPpHYwrmywOMQowMGo xMPb+KY3QIg1say4MvcQowQHs5II71JuoBBvSmJlVWpRfnxRaU5q8SFGaQ4WJXHeZo+UACGB 9MSS1OzU1ILUIpgsEwenVAOjzp0YnaYvi7jZtucvD17nK92nv/I/6/LlcXGlH41MZ8tYzRbb enkG69TKF0vCb6fprjmknLVwgZJXTOb8kl+z+qwtz27oWdHirtR7VfTb77ZWr1XCF8Q+fs6d 31m3L0d+hrfnNo4UzaL1nnMOFC3YJ3bLkrtS7cS2B5LlDjLVLmof0n//SZ6kxFKckWioxVxU nAgAhfcQSPoBAAA= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3822 Lines: 69 tasklet_kill() may sleep so call it before taking pch->lock. Fixes following lockup: [ 345.470000] BUG: scheduling while atomic: cat/2383/0x00000002 [ 345.470000] Modules linked in: [ 345.470000] [] (unwind_backtrace+0x0/0xfc) from [] (__schedule_bug+0x4c/0x58) [ 345.470000] [] (__schedule_bug+0x4c/0x58) from [] (__schedule+0x690/0x6e0) [ 345.470000] [] (__schedule+0x690/0x6e0) from [] (sys_sched_yield+0x70/0x78) [ 345.470000] [] (sys_sched_yield+0x70/0x78) from [] (tasklet_kill+0x34/0x8c) [ 345.470000] [] (tasklet_kill+0x34/0x8c) from [] (pl330_free_chan_resources+0x24/0x88) [ 345.470000] [] (pl330_free_chan_resources+0x24/0x88) from [] (dma_chan_put+0x4c/0x50) [ 345.470000] [] (dma_chan_put+0x4c/0x50) from [] (dma_release_channel+0x28/0x98) [...] [ 368.335000] BUG: spinlock lockup suspected on CPU#0, swapper/0/0 [ 368.340000] lock: 0xe52aa04c, .magic: dead4ead, .owner: cat/2383, .owner_cpu: 1 [ 368.350000] [] (unwind_backtrace+0x0/0xfc) from [] (do_raw_spin_lock+0x194/0x204) [ 368.360000] [] (do_raw_spin_lock+0x194/0x204) from [] (_raw_spin_lock_irqsave+0x20/0x28) [ 368.365000] [] (_raw_spin_lock_irqsave+0x20/0x28) from [] (pl330_tasklet+0x2c/0x5a8) [ 368.375000] [] (pl330_tasklet+0x2c/0x5a8) from [] (tasklet_action+0xfc/0x114) [ 368.385000] [] (tasklet_action+0xfc/0x114) from [] (__do_softirq+0xe4/0x19c) [ 368.395000] [] (__do_softirq+0xe4/0x19c) from [] (irq_exit+0x98/0x9c) [ 368.405000] [] (irq_exit+0x98/0x9c) from [] (handle_IPI+0x124/0x16c) [ 368.410000] [] (handle_IPI+0x124/0x16c) from [] (gic_handle_irq+0x64/0x68) [ 368.420000] [] (gic_handle_irq+0x64/0x68) from [] (__irq_svc+0x40/0x70) [ 368.430000] Exception stack(0xc04a3f00 to 0xc04a3f48) [ 368.435000] 3f00: c04a3f48 00000000 6f9e23e8 00000050 c07492c8 c04a3f48 00000000 c04ccc88 [ 368.440000] 3f20: 6f9dbac3 00000050 6f9e23e8 00000050 3b9aca00 c04a3f48 c005cfa4 c02946d4 [ 368.450000] 3f40: 60000013 ffffffff [ 368.455000] [] (__irq_svc+0x40/0x70) from [] (cpuidle_wrap_enter+0x4c/0xa0) [ 368.460000] [] (cpuidle_wrap_enter+0x4c/0xa0) from [] (cpuidle_enter_state+0x18/0x68) [ 368.470000] [] (cpuidle_enter_state+0x18/0x68) from [] (cpuidle_idle_call+0xac/0xe0) [ 368.480000] [] (cpuidle_idle_call+0xac/0xe0) from [] (cpu_idle+0xac/0xf0) [ 368.490000] [] (cpu_idle+0xac/0xf0) from [] (start_kernel+0x28c/0x294) Cc: Jassi Brar Cc: Vinod Koul Cc: Tomasz Figa Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Kyungmin Park --- drivers/dma/pl330.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 665668b..db7574b 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2459,10 +2459,10 @@ static void pl330_free_chan_resources(struct dma_chan *chan) struct dma_pl330_chan *pch = to_pchan(chan); unsigned long flags; - spin_lock_irqsave(&pch->lock, flags); - tasklet_kill(&pch->task); + spin_lock_irqsave(&pch->lock, flags); + pl330_release_channel(pch->pl330_chid); pch->pl330_chid = NULL; -- 1.8.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/