Hi Lucas, I didn't met your unstable console issue before, anyway, I'll do more test and look into Audio issue. -----Original Message----- From: Lucas Stach [mailto:l.stach@xxxxxxxxxxxxxx] Sent: 2018年6月14日 18:22 To: Robin Gong <yibin.gong@xxxxxxx>; s.hauer@xxxxxxxxxxxxxx; vkoul@xxxxxxxxxx; dan.j.williams@xxxxxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; jslaby@xxxxxxxx Cc: dmaengine@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; linux-serial@xxxxxxxxxxxxxxx Subject: Re: [PATCH v4 0/7] add virt-dma support for imx-sdma Am Donnerstag, den 14.06.2018, 10:09 +0000 schrieb Robin Gong: > Hi Lucas, > Could you double check again? Still can reproduce lockdep warning on > UART if change spin_lock_lockirqsave/spinlock_unlock_irqrestore to > spin_lock/spin_unlock in sdma_int_handler as you said without > patch7/7. Yes, I can reproduce the lockdep issue with _irqsave variants in the IRQ handler and 7/7 reverted. It fixes the pcm issue though. > Would you please ask below two more questions? > 1. Does your uart case pass now with my v4 patchset? It seems to work, but the change seems to impact the non-DMA serial somehow. On several boots the system was unable to present a login prompt, so patch 7/7 seems to break other stuff and it's a pretty invasive change to the serial driver, which is known to be non-trivial. I don't have the bandwidth to dig through this patch currently, but I wonder if it couldn't be simplified with the spinlock stuff in the sdma driver fixed. > 2. Do you make some code change in your local('I just gave this series > a spin')to reproduce your below issue? If yes, could you post your > change? The lockdep splat below was without any changes to your series. Regards, Lucas > On 四, 2018-06-14 at 10:53 +0200, Lucas Stach wrote: > > Hi Robin, > > > > I just gave this series a spin and it seems there is even more > > locking fun, see the lockdep output below. After taking a short look > > it seems this is caused by using the wrong spinlock variants in > > sdma_int_handler(), those should also use the _irqsave ones. When > > fixing this you might want to reconsider patch 7/7, as it's probably > > not needed at all. > > > > Regards, > > Lucas > > > > [ 20.479401] > > ======================================================== > > [ 20.485769] WARNING: possible irq lock inversion dependency > > detected [ 20.492140] 4.17.0+ #1538 Not tainted [ 20.495814] > > ---------------------------------------------------- > > -- > > -- > > [ 20.502181] systemd/1 just changed the state of lock: > > [ 20.507247] c0abdafc (&(&substream->self_group.lock)->rlock){- > > ...}, at: snd_pcm_stream_lock+0x54/0x60 [ 20.516523] but this lock > > took another, HARDIRQ-unsafe lock in the > > past: > > [ 20.523234] (fs_reclaim){+.+.} > > [ 20.523253] > > [ 20.523253] > > [ 20.523253] and interrupts could create inverse lock ordering > > between them. > > [ 20.523253] > > [ 20.537804] > > [ 20.537804] other info that might help us debug this: > > [ 20.544344] Possible interrupt unsafe locking scenario: > > [ 20.544344] > > [ 20.551144] CPU0 CPU1 [ 20.555686] > > ---- ---- [ 20.560224] lock(fs_reclaim); [ > > 20.563386] local_irq_disable(); [ > > 20.569315] lock(&(&substream- > > > self_group.lock)->rlock); > > > > [ 20.577337] lock(fs_reclaim); [ > > 20.583014] <Interrupt> [ 20.585643] > > lock(&(&substream->self_group.lock)->rlock); > > [ 20.591322] > > [ 20.591322] *** DEADLOCK *** > > [ 20.591322] > > [ 20.597260] 1 lock held by systemd/1: > > [ 20.607806] #0: ab23d11c (snd_pcm_link_rwlock){.-..}, at: > > snd_pcm_stream_lock+0x4c/0x60 > > [ 20.615951] > > [ 20.615951] the shortest dependencies between 2nd lock and 1st > > lock: > > [ 20.623799] -> (fs_reclaim){+.+.} ops: 248474 { [ 20.628456] > > HARDIRQ-ON-W at: > > [ 20.631716] lock_acquire+0x260/0x29c [ > > 20.637223] fs_reclaim_acquire+0x48/0x58 [ > > 20.643075] kmem_cache_alloc_trace+0x3c/0x > > 36 > > 4 > > [ 20.649366] alloc_worker.constprop.15+0x28 > > /0 > > x64 > > [ 20.655824] init_rescuer.part.5+0x20/0xa4 [ > > 20.661764] workqueue_init+0x124/0x1f8 [ > > 20.667446] kernel_init_freeable+0x60/0x55 > > 0 > > [ 20.673561] kernel_init+0x18/0x120 [ > > 20.678890] ret_from_fork+0x14/0x20 [ > > 20.684299] (null) [ 20.688408] > > SOFTIRQ-ON-W at: > > [ 20.691659] lock_acquire+0x260/0x29c [ > > 20.697158] fs_reclaim_acquire+0x48/0x58 [ > > 20.703006] kmem_cache_alloc_trace+0x3c/0x > > 36 > > 4 > > [ 20.709288] alloc_worker.constprop.15+0x28 > > /0 > > x64 > > [ 20.709301] init_rescuer.part.5+0x20/0xa4 [ > > 20.720717] workqueue_init+0x124/0x1f8 [ > > 20.720729] kernel_init_freeable+0x60/0x55 > > 0 > > [ 20.720738] kernel_init+0x18/0x120 [ > > 20.720746] ret_from_fork+0x14/0x20 [ > > 20.720751] (null) [ 20.720756] INITIAL > > USE at: > > [ 20.720770] lock_acquire+0x260/0x29c [ > > 20.720782] fs_reclaim_acquire+0x48/0x58 [ > > 20.774374] kmem_cache_alloc_trace+0x3c/0x3 > > 64 > > [ 20.780574] alloc_worker.constprop.15+0x28/ > > 0x > > 64 > > [ 20.786945] init_rescuer.part.5+0x20/0xa4 [ > > 20.792794] workqueue_init+0x124/0x1f8 [ > > 20.798384] kernel_init_freeable+0x60/0x550 [ > > 20.804406] kernel_init+0x18/0x120 [ > > 20.809648] ret_from_fork+0x14/0x20 [ > > 20.814971] (null) [ 20.818992] } [ > > 20.820768] ... key at: [<80e22074>] > > __fs_reclaim_map+0x0/0x10 > > [ 20.827220] ... acquired at: > > [ 20.830289] fs_reclaim_acquire+0x48/0x58 [ 20.834487] > > kmem_cache_alloc_trace+0x3c/0x364 [ 20.839123] > > sdma_transfer_init+0x44/0x130 [ 20.843409] > > sdma_prep_dma_cyclic+0x78/0x21c [ 20.847869] > > snd_dmaengine_pcm_trigger+0xdc/0x184 > > [ 20.852764] soc_pcm_trigger+0x164/0x190 [ 20.856876] > > snd_pcm_do_start+0x34/0x40 [ 20.860902] > > snd_pcm_action_single+0x48/0x74 [ 20.865360] > > snd_pcm_action+0x34/0xfc [ 20.869213] > > snd_pcm_ioctl+0x910/0x10ec [ 20.873241] vfs_ioctl+0x30/0x44 [ > > 20.876657] do_vfs_ioctl+0xac/0x974 [ 20.880421] > > ksys_ioctl+0x48/0x64 [ 20.883923] sys_ioctl+0x18/0x1c [ > > 20.887340] ret_fast_syscall+0x0/0x28 [ 20.891277] 0x7289bcbc > > [ 20.893909] [ 20.895410] -> > > (&(&substream->self_group.lock)->rlock){-...} > > ops: > > 59 { > > [ 20.901977] IN-HARDIRQ-W at: > > [ 20.905143] lock_acquire+0x260/0x29c [ > > 20.910473] _raw_spin_lock+0x48/0x58 [ > > 20.915801] snd_pcm_stream_lock+0x54/0x60 [ > > 20.921561] _snd_pcm_stream_lock_irqsave+0x4 0/ > > 0x48 > > [ 20.928107] snd_pcm_period_elapsed+0x2c/0xa4 > > [ 20.934127] dmaengine_pcm_dma_complete+0x54/ > > 0x > > 58 > > [ 20.940498] sdma_int_handler+0x1dc/0x2a8 [ > > 20.946179] __handle_irq_event_percpu+0x1fc/ 0x > > 498 > > [ 20.952635] handle_irq_event_percpu+0x38/0x8 > > c [ 20.958742] handle_irq_event+0x48/0x6c [ > > 20.964242] handle_fasteoi_irq+0xc4/0x138 [ > > 20.970006] generic_handle_irq+0x28/0x38 [ > > 20.975681] __handle_domain_irq+0xb0/0xc4 [ > > 20.981443] gic_handle_irq+0x68/0xa0 [ > > 20.986769] __irq_svc+0x70/0xb0 [ 20.991662] > > _raw_spin_unlock_irq+0x38/0x6c [ 20.997511] > > task_work_run+0x90/0xb8 [ 21.002751] > > do_work_pending+0xc8/0xd0 [ 21.008164] > > slow_work_pending+0xc/0x20 [ 21.013661] > > 0x76c77e86 [ 21.017768] INITIAL USE at: > > [ 21.020844] lock_acquire+0x260/0x29c [ > > 21.026086] _raw_spin_lock+0x48/0x58 [ > > 21.031328] snd_pcm_stream_lock+0x54/0x60 [ > > 21.037002] snd_pcm_stream_lock_irq+0x38/0x3c [ > > 21.043023] snd_pcm_sync_ptr+0x214/0x260 [ > > 21.048609] snd_pcm_ioctl+0xbe0/0x10ec [ > > 21.054027] vfs_ioctl+0x30/0x44 [ 21.058832] > > do_vfs_ioctl+0xac/0x974 [ 21.063984] > > ksys_ioctl+0x48/0x64 [ 21.068875] > > sys_ioctl+0x18/0x1c [ 21.073679] > > ret_fast_syscall+0x0/0x28 [ 21.079004] > > 0x7e9026dc [ 21.083023] } [ 21.084710] ... key at: > > [<8162a6e4>] __key.31798+0x0/0x8 [ 21.090552] ... acquired at: > > [ 21.093537] mark_lock+0x3a4/0x69c [ 21.097128] > > __lock_acquire+0x420/0x16d4 [ 21.101239] > > lock_acquire+0x260/0x29c [ 21.105091] _raw_spin_lock+0x48/0x58 > > [ 21.108940] snd_pcm_stream_lock+0x54/0x60 [ 21.113226] > > _snd_pcm_stream_lock_irqsave+0x40/0x48 > > [ 21.118296] snd_pcm_period_elapsed+0x2c/0xa4 [ 21.122841] > > dmaengine_pcm_dma_complete+0x54/0x58 > > [ 21.127735] sdma_int_handler+0x1dc/0x2a8 [ 21.131937] > > __handle_irq_event_percpu+0x1fc/0x498 > > [ 21.136915] handle_irq_event_percpu+0x38/0x8c [ 21.141547] > > handle_irq_event+0x48/0x6c [ 21.145570] > > handle_fasteoi_irq+0xc4/0x138 [ 21.149854] > > generic_handle_irq+0x28/0x38 [ 21.154052] > > __handle_domain_irq+0xb0/0xc4 [ 21.158335] > > gic_handle_irq+0x68/0xa0 [ 21.162184] __irq_svc+0x70/0xb0 [ > > 21.165601] _raw_spin_unlock_irq+0x38/0x6c [ 21.169973] > > task_work_run+0x90/0xb8 [ 21.173735] do_work_pending+0xc8/0xd0 > > [ 21.177670] slow_work_pending+0xc/0x20 [ 21.181691] > > 0x76c77e86 [ 21.184320] [ 21.185821] [ 21.185821] stack > > backtrace: > > [ 21.190198] CPU: 0 PID: 1 Comm: systemd Not tainted 4.17.0+ > > #1538 > > [ 21.196303] Hardware name: Freescale i.MX6 Quad/DualLite (Device > > Tree) > > [ 21.202841] Backtrace: > > [ 21.205314] [<8010e318>] (dump_backtrace) from [<8010e604>] > > (show_stack+0x20/0x24) > > [ 21.212900] r7:80e9f3d0 r6:00000000 r5:60070193 r4:80e9f3d0 [ > > 21.218581] [<8010e5e4>] (show_stack) from [<8099b660>] > > (dump_stack+0xa4/0xd8) > > [ 21.225825] [<8099b5bc>] (dump_stack) from [<8017b52c>] > > (print_irq_inversion_bug+0x15c/0x1fc) > > [ 21.234368] r9:814da818 r8:00000001 r7:ee926c00 r6:00000000 > > r5:ee915bb0 r4:814da818 > > [ 21.242133] [<8017b3d0>] (print_irq_inversion_bug) from > > [<8017b6dc>] (check_usage_forwards+0x110/0x13c) > > [ 21.251544] r9:00000002 r8:80bfd3e2 r7:ee926c00 r6:ee927148 > > r5:80e08488 r4:00000001 > > [ 21.259306] [<8017b5cc>] (check_usage_forwards) from [<8017c2a4>] > > (mark_lock+0x3a4/0x69c) > > [ 21.267500] r9:ee926c00 r8:80a03cd8 r7:00000101 r6:00000002 > > r5:00000000 r4:ee927148 > > [ 21.275263] [<8017bf00>] (mark_lock) from [<8017cf68>] > > (__lock_acquire+0x420/0x16d4) > > [ 21.283023] r10:ee927148 r9:ed4620e4 r8:ee926c00 r7:00000000 > > r6:00000001 r5:00000001 > > [ 21.290863] r4:00000490 > > [ 21.293416] [<8017cb48>] (__lock_acquire) from [<8017ed58>] > > (lock_acquire+0x260/0x29c) > > [ 21.301350] r10:00000001 r9:80e084a4 r8:00000000 r7:00000000 > > r6:00000000 r5:ed4620e4 > > [ 21.309189] r4:00000000 > > [ 21.311746] [<8017eaf8>] (lock_acquire) from [<809b74f0>] > > (_raw_spin_lock+0x48/0x58) > > [ 21.319506] r10:ee0a4714 r9:ed457100 r8:ee0a46c8 r7:ee0a4714 > > r6:ee0a4010 r5:807847b0 > > [ 21.327346] r4:ed4620d4 > > [ 21.329902] [<809b74a8>] (_raw_spin_lock) from [<807847b0>] > > (snd_pcm_stream_lock+0x54/0x60) > > [ 21.338265] r5:ed462000 r4:ed462000 [ 21.341863] [<8078475c>] > > (snd_pcm_stream_lock) from [<80784838>] > > (_snd_pcm_stream_lock_irqsave+0x40/0x48) > > [ 21.351440] r5:ed462000 r4:60070193 [ 21.355042] [<807847f8>] > > (_snd_pcm_stream_lock_irqsave) from [<8078b044>] > > (snd_pcm_period_elapsed+0x2c/0xa4) > > [ 21.364881] r5:ee3ef000 r4:ed462000 [ 21.368478] [<8078b018>] > > (snd_pcm_period_elapsed) from [<8078d7b4>] > > (dmaengine_pcm_dma_complete+0x54/0x58) > > [ 21.378148] r7:ee0a4714 r6:ee0a4010 r5:00000007 r4:ee0a46bc [ > > 21.383827] [<8078d760>] (dmaengine_pcm_dma_complete) from > > [<80504c0c>] (sdma_int_handler+0x1dc/0x2a8) [ 21.393157] > > [<80504a30>] (sdma_int_handler) from [<8018cd28>] > > (__handle_irq_event_percpu+0x1fc/0x498) > > [ 21.402393] r10:00000000 r9:eeafd400 r8:80e084a4 r7:00000038 > > r6:00000038 r5:80ea3c12 > > [ 21.410233] r4:ee2b5d40 > > [ 21.412787] [<8018cb2c>] (__handle_irq_event_percpu) from > > [<8018cffc>] (handle_irq_event_percpu+0x38/0x8c) > > [ 21.422457] r10:00000000 r9:ee914000 r8:ee81d400 r7:00000038 > > r6:eeafd400 r5:eeafd464 > > [ 21.430296] r4:80e08488 > > [ 21.432852] [<8018cfc4>] (handle_irq_event_percpu) from > > [<8018d098>] (handle_irq_event+0x48/0x6c) [ 21.441736] > > r6:eeafd464 r5:eeafd464 r4:eeafd400 [ 21.446374] [<8018d050>] > > (handle_irq_event) from [<8019146c>] > > (handle_fasteoi_irq+0xc4/0x138) > > [ 21.454912] r7:00000038 r6:eeafd464 r5:80e10a60 r4:eeafd400 [ > > 21.460589] [<801913a8>] (handle_fasteoi_irq) from [<8018bd9c>] > > (generic_handle_irq+0x28/0x38) > > [ 21.469214] r7:00000038 r6:80d92ae4 r5:00000000 r4:00000000 [ > > 21.474893] [<8018bd74>] (generic_handle_irq) from [<8018c48c>] > > (__handle_domain_irq+0xb0/0xc4) > > [ 21.483611] [<8018c3dc>] (__handle_domain_irq) from [<80102330>] > > (gic_handle_irq+0x68/0xa0) > > [ 21.491978] r9:ee914000 r8:f4001100 r7:80e5c6bc r6:ee915f00 > > r5:80e08c3c r4:f4000100 [ 21.499738] [<801022c8>] (gic_handle_irq) > > from [<801019f0>] > > (__irq_svc+0x70/0xb0) > > [ 21.507233] Exception stack(0xee915f00 to 0xee915f48) [ > > 21.512303] 5f00: 00000001 00000004 00000000 ee926c00 ee9270a8 > > ee926c00 ecc45e00 ee9270a8 > > [ 21.520498] 5f20: 80ec23b0 ee914000 00000000 ee915f64 ee915f20 > > ee915f50 8017c7c0 809b78ac > > [ 21.528687] 5f40: 20070013 ffffffff [ 21.532193] r9:ee914000 > > r8:80ec23b0 r7:ee915f34 r6:ffffffff > > r5:20070013 r4:809b78ac > > [ 21.539959] [<809b7874>] (_raw_spin_unlock_irq) from [<8014e98c>] > > (task_work_run+0x90/0xb8) > > [ 21.548321] r5:ee926c00 r4:ecc45e00 [ 21.551913] [<8014e8fc>] > > (task_work_run) from [<8010da3c>] > > (do_work_pending+0xc8/0xd0) > > [ 21.559848] r9:ee914000 r8:801011c4 r7:ee915fb0 r6:ffffe000 > > r5:00000004 r4:801011c4 > > [ 21.567608] [<8010d974>] (do_work_pending) from [<80101034>] > > (slow_work_pending+0xc/0x20) > > [ 21.575797] Exception stack(0xee915fb0 to 0xee915ff8) [ > > 21.580864] 5fa0: 00000000 > > 020c34e8 46059f00 00000000 > > [ 21.589059] 5fc0: 00000002 76f133a4 020df680 00000006 76e6e168 > > 00000035 7ef81778 00000035 > > [ 21.597253] 5fe0: 00000006 7ef816a0 76c75d67 76c77e86 20070030 > > 00000039 > > [ 21.603883] r7:00000006 r6:020df680 r5:76f133a4 r4:00000002 > > > > Am Donnerstag, den 14.06.2018, 22:02 +0800 schrieb Robin Gong: > > > > > > The legacy sdma driver has below limitations or drawbacks: > > > 1. Hardcode the max BDs number as "PAGE_SIZE / sizeof(*)", and > > > alloc > > > one page size for one channel regardless of only few BDs > > > needed > > > most time. But in few cases, the max PAGE_SIZE maybe not > > > enough. > > > 2. One SDMA channel can't stop immediatley once channel disabled > > > which > > > means SDMA interrupt may come in after this channel > > > terminated.There > > > are some patches for this corner case such as commit > > > "2746e2c389f9", > > > but not cover non-cyclic. > > > > > > The common virt-dma overcomes the above limitations. It can alloc > > > bd dynamically and free bd once this tx transfer done. No memory > > > wasted or maximum limititation here, only depends on how many > > > memory can be requested from kernel. For No.2, such issue can be > > > workaround by checking if there is available > > > descript("sdmac->desc") now once the unwanted interrupt coming. At > > > last the common virt-dma is easier for sdma driver maintain. > > > > > > Change from v3: > > > 1. add two uart patches which impacted by this patchset. > > > 2. unlock 'vc.lock' before cyclic dma callback and lock again > > > after > > > it because some driver such as uart will call > > > dmaengine_tx_status > > > which will acquire 'vc.lock' again and dead lock comes out. > > > 3. remove 'Revert commit' stuff since that patch is not wrong > > > and > > > combine two patch into one patch as Sascha's comment. > > > > > > Change from v2: > > > 1. include Sascha's patch to make the main patch easier to > > > review. > > > Thanks Sacha. > > > 2. remove useless 'desc'/'chan' in struct sdma_channe. > > > > > > Change from v1: > > > 1. split v1 patch into 5 patches. > > > 2. remove some unnecessary condition check. > > > 3. remove unnecessary 'pending' list. > > > > > > Robin Gong (6): > > > tty: serial: imx: correct dma cookie status > > > dmaengine: imx-sdma: add virt-dma support > > > dmaengine: imx-sdma: remove useless 'lock' and 'enabled' in > > > 'struct > > > sdma_channel' > > > dmaengine: imx-sdma: remove the maximum limitation for bd > > > numbers > > > dmaengine: imx-sdma: add sdma_transfer_init to decrease code > > > overlap > > > tty: serial: imx: split all dma setup operations out of > > > 'port.lock' > > > protector > > > > > > Sascha Hauer (1): > > > dmaengine: imx-sdma: factor out a struct sdma_desc from struct > > > sdma_channel > > > > > > drivers/dma/Kconfig | 1 + > > > drivers/dma/imx-sdma.c | 394 +++++++++++++++++++++++++++------ > > > -------------- > > > drivers/tty/serial/imx.c | 99 ++++++------ > > > 3 files changed, 282 insertions(+), 212 deletions(-) ��.n��������+%������w��{.n�����{��ǫ����{ay� ʇڙ���f���h������_�(�階�ݢj"��������G����?���&��
