This patch is already approved by "Vinod Koul <vinod.koul@xxxxxxxxx>" Thanks. Best Regards. > -----Original Message----- > From: stable-owner@xxxxxxxxxxxxxxx [mailto:stable-owner@xxxxxxxxxxxxxxx] > On Behalf Of Jonghwan Choi > Sent: Thursday, October 10, 2013 2:16 PM > To: 'Jonghwan Choi' > Cc: stable@xxxxxxxxxxxxxxx; 'Michael Grzeschik'; 'Vinod Koul'; > cpgs@xxxxxxxxxxx > Subject: [PATCH 3.11-stable] dmaengine: imx-dma: fix lockdep issue between > irqhandler and tasklet > > This patch looks like it should be in the 3.11-stable tree, should we > apply > it? > > ------------------ > > From: "Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx>" > > commit 5a276fa6bdf82fd442046969603968c83626ce0b upstream > > The tasklet and irqhandler are using spin_lock while other routines are > using spin_lock_irqsave/restore. This leads to lockdep issues as > described bellow. This patch is changing the code to use > spinlock_irq_save/restore in both code pathes. > > As imxdma_xfer_desc always gets called with spin_lock_irqsave lock held, > this patch also removes the spare call inside the routine to avoid > double locking. > > [ 403.358162] ================================= > [ 403.362549] [ INFO: inconsistent lock state ] > [ 403.366945] 3.10.0-20130823+ #904 Not tainted > [ 403.371331] --------------------------------- > [ 403.375721] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage. > [ 403.381769] swapper/0 [HC0[0]:SC1[1]:HE1:SE0] takes: > [ 403.386762] (&(&imxdma->lock)->rlock){?.-...}, at: [<c019d77c>] > imxdma_tasklet+0x20/0x134 > [ 403.395201] {IN-HARDIRQ-W} state was registered at: > [ 403.400108] [<c004b264>] mark_lock+0x2a0/0x6b4 > [ 403.404798] [<c004d7c8>] __lock_acquire+0x650/0x1a64 > [ 403.410004] [<c004f15c>] lock_acquire+0x94/0xa8 > [ 403.414773] [<c02f74e4>] _raw_spin_lock+0x54/0x8c > [ 403.419720] [<c019d094>] dma_irq_handler+0x78/0x254 > [ 403.424845] [<c0061124>] handle_irq_event_percpu+0x38/0x1b4 > [ 403.430670] [<c00612e4>] handle_irq_event+0x44/0x64 > [ 403.435789] [<c0063a70>] handle_level_irq+0xd8/0xf0 > [ 403.440903] [<c0060a20>] generic_handle_irq+0x28/0x38 > [ 403.446194] [<c0009cc4>] handle_IRQ+0x68/0x8c > [ 403.450789] [<c0008714>] avic_handle_irq+0x3c/0x48 > [ 403.455811] [<c0008f84>] __irq_svc+0x44/0x74 > [ 403.460314] [<c0040b04>] cpu_startup_entry+0x88/0xf4 > [ 403.465525] [<c02f00d0>] rest_init+0xb8/0xe0 > [ 403.470045] [<c03e07dc>] start_kernel+0x28c/0x2d4 > [ 403.474986] [<a0008040>] 0xa0008040 > [ 403.478709] irq event stamp: 50854 > [ 403.482140] hardirqs last enabled at (50854): [<c001c6b8>] > tasklet_action+0x38/0xdc > [ 403.489954] hardirqs last disabled at (50853): [<c001c6a0>] > tasklet_action+0x20/0xdc > [ 403.497761] softirqs last enabled at (50850): [<c001bc64>] > _local_bh_enable+0x14/0x18 > [ 403.505741] softirqs last disabled at (50851): [<c001c268>] > irq_exit+0x88/0xdc > [ 403.513026] > [ 403.513026] other info that might help us debug this: > [ 403.519593] Possible unsafe locking scenario: > [ 403.519593] > [ 403.525548] CPU0 > [ 403.528020] ---- > [ 403.530491] lock(&(&imxdma->lock)->rlock); > [ 403.534828] <Interrupt> > [ 403.537474] lock(&(&imxdma->lock)->rlock); > [ 403.541983] > [ 403.541983] *** DEADLOCK *** > [ 403.541983] > [ 403.547951] no locks held by swapper/0. > [ 403.551813] > [ 403.551813] stack backtrace: > [ 403.556222] CPU: 0 PID: 0 Comm: swapper Not tainted 3.10.0-20130823+ > #904 > [ 403.563039] Backtrace: > [ 403.565581] [<c000b98c>] (dump_backtrace+0x0/0x10c) from [<c000bb28>] > (show_stack+0x18/0x1c) > [ 403.574054] r6:00000000 r5:c05c51d8 r4:c040bd58 r3:00200000 > [ 403.579872] [<c000bb10>] (show_stack+0x0/0x1c) from [<c02f398c>] > (dump_stack+0x20/0x28) > [ 403.587955] [<c02f396c>] (dump_stack+0x0/0x28) from [<c02f29c8>] > (print_usage_bug.part.28+0x224/0x28c) > [ 403.597340] [<c02f27a4>] (print_usage_bug.part.28+0x0/0x28c) from > [<c004b404>] (mark_lock+0x440/0x6b4) > [ 403.606682] r8:c004a41c r7:00000000 r6:c040bd58 r5:c040c040 r4:00000002 > [ 403.613566] [<c004afc4>] (mark_lock+0x0/0x6b4) from [<c004d844>] > (__lock_acquire+0x6cc/0x1a64) > [ 403.622244] [<c004d178>] (__lock_acquire+0x0/0x1a64) from [<c004f15c>] > (lock_acquire+0x94/0xa8) > [ 403.631010] [<c004f0c8>] (lock_acquire+0x0/0xa8) from [<c02f74e4>] > (_raw_spin_lock+0x54/0x8c) > [ 403.639614] [<c02f7490>] (_raw_spin_lock+0x0/0x8c) from [<c019d77c>] > (imxdma_tasklet+0x20/0x134) > [ 403.648434] r6:c3847010 r5:c040e890 r4:c38470d4 > [ 403.653194] [<c019d75c>] (imxdma_tasklet+0x0/0x134) from [<c001c70c>] > (tasklet_action+0x8c/0xdc) > [ 403.662013] r8:c0599160 r7:00000000 r6:00000000 r5:c040e890 r4:c3847114 > r3:c019d75c > [ 403.670042] [<c001c680>] (tasklet_action+0x0/0xdc) from [<c001bd4c>] > (__do_softirq+0xe4/0x1f0) > [ 403.678687] r7:00000101 r6:c0402000 r5:c059919c r4:00000001 > [ 403.684498] [<c001bc68>] (__do_softirq+0x0/0x1f0) from [<c001c268>] > (irq_exit+0x88/0xdc) > [ 403.692652] [<c001c1e0>] (irq_exit+0x0/0xdc) from [<c0009cc8>] > (handle_IRQ+0x6c/0x8c) > [ 403.700514] r4:00000030 r3:00000110 > [ 403.704192] [<c0009c5c>] (handle_IRQ+0x0/0x8c) from [<c0008714>] > (avic_handle_irq+0x3c/0x48) > [ 403.712664] r5:c0403f28 r4:c0593ebc > [ 403.716343] [<c00086d8>] (avic_handle_irq+0x0/0x48) from [<c0008f84>] > (__irq_svc+0x44/0x74) > [ 403.724733] Exception stack(0xc0403f28 to 0xc0403f70) > [ 403.729841] 3f20: 00000001 00000004 00000000 20000013 > c0402000 c04104a8 > [ 403.738078] 3f40: 00000002 c0b69620 a0004000 41069264 a03fb5f4 c0403f7c > c0403f40 c0403f70 > [ 403.746301] 3f60: c004b92c c0009e74 20000013 ffffffff > [ 403.751383] r6:ffffffff r5:20000013 r4:c0009e74 r3:c004b92c > [ 403.757210] [<c0009e30>] (arch_cpu_idle+0x0/0x4c) from [<c0040b04>] > (cpu_startup_entry+0x88/0xf4) > [ 403.766161] [<c0040a7c>] (cpu_startup_entry+0x0/0xf4) from [<c02f00d0>] > (rest_init+0xb8/0xe0) > [ 403.774753] [<c02f0018>] (rest_init+0x0/0xe0) from [<c03e07dc>] > (start_kernel+0x28c/0x2d4) > [ 403.783051] r6:c03fc484 r5:ffffffff r4:c040a0e0 > [ 403.787797] [<c03e0550>] (start_kernel+0x0/0x2d4) from [<a0008040>] > (0xa0008040) > > Cc: <stable@xxxxxxxxxxxxxxx> # 3.11.x: edc530f: dmaengine: imx-dma: fix > slow path > Signed-off-by: Michael Grzeschik <m.grzeschik@xxxxxxxxxxxxxx> > Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx> > Signed-off-by: Jonghwan Choi <jhbird.choi@xxxxxxxxxxx> > --- > drivers/dma/imx-dma.c | 19 ++++++++----------- > 1 file changed, 8 insertions(+), 11 deletions(-) > > diff --git a/drivers/dma/imx-dma.c b/drivers/dma/imx-dma.c > index ff2aab9..8b43b25 100644 > --- a/drivers/dma/imx-dma.c > +++ b/drivers/dma/imx-dma.c > @@ -437,17 +437,18 @@ static void dma_irq_handle_channel(struct > imxdma_channel *imxdmac) > struct imxdma_engine *imxdma = imxdmac->imxdma; > int chno = imxdmac->channel; > struct imxdma_desc *desc; > + unsigned long flags; > > - spin_lock(&imxdma->lock); > + spin_lock_irqsave(&imxdma->lock, flags); > if (list_empty(&imxdmac->ld_active)) { > - spin_unlock(&imxdma->lock); > + spin_unlock_irqrestore(&imxdma->lock, flags); > goto out; > } > > desc = list_first_entry(&imxdmac->ld_active, > struct imxdma_desc, > node); > - spin_unlock(&imxdma->lock); > + spin_unlock_irqrestore(&imxdma->lock, flags); > > if (desc->sg) { > u32 tmp; > @@ -519,7 +520,6 @@ static int imxdma_xfer_desc(struct imxdma_desc *d) > { > struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan); > struct imxdma_engine *imxdma = imxdmac->imxdma; > - unsigned long flags; > int slot = -1; > int i; > > @@ -527,7 +527,6 @@ static int imxdma_xfer_desc(struct imxdma_desc *d) > switch (d->type) { > case IMXDMA_DESC_INTERLEAVED: > /* Try to get a free 2D slot */ > - spin_lock_irqsave(&imxdma->lock, flags); > for (i = 0; i < IMX_DMA_2D_SLOTS; i++) { > if ((imxdma->slots_2d[i].count > 0) && > ((imxdma->slots_2d[i].xsr != d->x) || > @@ -537,10 +536,8 @@ static int imxdma_xfer_desc(struct imxdma_desc *d) > slot = i; > break; > } > - if (slot < 0) { > - spin_unlock_irqrestore(&imxdma->lock, flags); > + if (slot < 0) > return -EBUSY; > - } > > imxdma->slots_2d[slot].xsr = d->x; > imxdma->slots_2d[slot].ysr = d->y; > @@ -549,7 +546,6 @@ static int imxdma_xfer_desc(struct imxdma_desc *d) > > imxdmac->slot_2d = slot; > imxdmac->enabled_2d = true; > - spin_unlock_irqrestore(&imxdma->lock, flags); > > if (slot == IMX_DMA_2D_SLOT_A) { > d->config_mem &= ~CCR_MSEL_B; > @@ -625,8 +621,9 @@ static void imxdma_tasklet(unsigned long data) > struct imxdma_channel *imxdmac = (void *)data; > struct imxdma_engine *imxdma = imxdmac->imxdma; > struct imxdma_desc *desc; > + unsigned long flags; > > - spin_lock(&imxdma->lock); > + spin_lock_irqsave(&imxdma->lock, flags); > > if (list_empty(&imxdmac->ld_active)) { > /* Someone might have called terminate all */ > @@ -663,7 +660,7 @@ static void imxdma_tasklet(unsigned long data) > __func__, imxdmac->channel); > } > out: > - spin_unlock(&imxdma->lock); > + spin_unlock_irqrestore(&imxdma->lock, flags); > } > > static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe stable" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html