Messages in this thread | | | Subject | Re: mmc: dw_mmc: warning with CONFIG_DMA_API_DEBUG | From | Shawn Lin <> | Date | Fri, 24 Jun 2016 09:25:01 +0800 |
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Hi Jaehoon,
On 2016/6/23 19:39, Jaehoon Chung wrote: > Hi Shawn, > > On 06/21/2016 04:39 PM, Shawn Lin wrote: >> 在 2016/6/21 13:32, Jaehoon Chung 写道: >>> Hi guys, >>> >>> On 06/21/2016 11:31 AM, Shawn Lin wrote: >>>> On 2016/6/21 10:24, Seung-Woo Kim wrote: >>>>> Hello Shawn, >>>>> >>>>>> -----Original Message----- >>>>>> From: Shawn Lin [mailto:shawn.lin@rock-chips.com] >>>>>> Sent: Tuesday, June 21, 2016 10:52 AM >>>>>> To: Seung-Woo Kim; jh80.chung@samsung.com; ulf.hansson@linaro.org; linux-mmc@vger.kernel.org; linux- >>>>>> kernel@vger.kernel.org >>>>>> Cc: shawn.lin@rock-chips.com >>>>>> Subject: Re: mmc: dw_mmc: warning with CONFIG_DMA_API_DEBUG >>>>>> >>>>>> On 2016/6/20 16:34, Seung-Woo Kim wrote: >>>>>>> Hi folks, >>>>>>> >>>>>>> During booting test on my Exynos5422 based Odroid-XU3, kernel compiled >>>>>>> with CONFIG_DMA_API_DEBUG reported following warning: >>>>>>> >>>>>>> ------------[ cut here ]------------ >>>>>>> WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1096 check_unmap+0x7bc/0xb38 >>>>>>> dwmmc_exynos 12200000.mmc: DMA-API: device driver tries to free DMA memory it has not allocated [device >>>>>> address=0x000000006d9d2200] >>>>>> >>>>>> Thanks for this report and fix. >>>>>> >>>>>> DTO(the same as IDMAC-RI/TI) interrupts may or may not come together >>>>>> with DATA_ERR. If DATA_ERR occur without geting DTO, we should issue >>>>>> CMD12 manually to generate DTO. It's a ugly deisgn for dwmmc but from >>>>>> the vendor's ask. >>>>>> >>>>>> So you should never think we complete the xfer without >>>>>> checking DATA_ERR. This way you got the warning. >>> >>> Well, EVENT_DATA_ERR is already checked in tasklet_func..and cleared that flags. >> >> From my view, the reality is that when we got DATA_ERROR interrupts, >> we set EVENT_DATA_ERR to the pending_events and schedule the tasklet >> but we may still fallback to the IDMAC interrupt case as the tasklet >> may come up a little late, namely right after the IDMAC interrupt checking. >> >> I'm trying to add some log there, and it well proves my guess. > > You're right..This is appeared because of "Data Over". > If Data Over interrupt is occurred, SW needs to read the remaining Data in FIFO. > At that time, it was set to DATA_COMPLETE. Because SW might read the remaining data, but already set to ERROR_DATA. > > In this case, Your suggestion may prevent to free twice. > > There is other case..during tuning sequence.. :( > I found that it also appeared during the tuning sequence. > - Really..stupid design.. > > My suggestions are > First, apply the below solution.
Which solution? This $SUBJECT or the one I sent?
> And then consider the HS200 tuning block with the below patch. > > https://patchwork.kernel.org/patch/8935791/
I saw this patch long ago, but I still have not seen this issue or got reports for it. From the code itself, it should be ok to landed as I checked the databook. :)
> > How about? > Do you have any other opinion? > > Best Regards, > Jaehoon Chung > >> >>> >>>>>> >>>>>> So could you try this one: >>>>> >>>>> With your patch, there is no more the DMA API waring in my environment. >>>> >>>> Nice to hear that. Thanks for testing, Seung-Woo. >>> >>> Really? It's not solution..When send tuning command, it should be returned CRC error. >>> Then it called the dw_mci_stop_dma() and also dma_ops->complete(). >> >> Hrmm.. I can't see the reason it will also call dma_ops->complete. >> Could you explain a bit more here? :) >> >> From V2.70a Table 3-2 >> For MMC CMD19, there may be no CRC status returned by the >> card but EBE is generated. Hence, EBE is set for CMD19. The application >> should not treat this as an error. >> >> >>> >>> When i applied you suggestion, also produced.. :) >>> >>> [ 2.469916] [<c010d6f0>] (unwind_backtrace) from [<c010a478>] (show_stack+0x10/0x14) >>> [ 2.469934] [<c010a478>] (show_stack) from [<c031b324>] (dump_stack+0x74/0x94) >>> [ 2.469949] [<c031b324>] (dump_stack) from [<c011b5ac>] (__warn+0xd4/0x100) >>> [ 2.469961] [<c011b5ac>] (__warn) from [<c011b678>] (warn_slowpath_fmt+0x38/0x48) >>> [ 2.469975] [<c011b678>] (warn_slowpath_fmt) from [<c033ee20>] (check_unmap+0x828/0x8a8) >>> [ 2.469991] [<c033ee20>] (check_unmap) from [<c033f7c0>] (debug_dma_unmap_sg+0x5c/0x13c) >>> [ 2.470012] [<c033f7c0>] (debug_dma_unmap_sg) from [<c051e6a4>] (dw_mci_dma_cleanup+0x68/0xa4) >>> [ 2.470029] [<c051e6a4>] (dw_mci_dma_cleanup) from [<c0553bf4>] (dw_mci_stop_dma+0x30/0x40) >>> [ 2.470045] [<c0553bf4>] (dw_mci_stop_dma) from [<c0521b30>] (dw_mci_tasklet_func+0x340/0x3b4) >>> [ 2.470063] [<c0521b30>] (dw_mci_tasklet_func) from [<c011fcb0>] (tasklet_action+0x84/0x12c) >>> [ 2.470076] [<c011fcb0>] (tasklet_action) from [<c011f35c>] (__do_softirq+0xec/0x244) >>> [ 2.470089] [<c011f35c>] (__do_softirq) from [<c011f750>] (irq_exit+0xb4/0xf8) >>> [ 2.470109] [<c011f750>] (irq_exit) from [<c015d004>] (__handle_domain_irq+0x70/0xe4) >>> [ 2.470123] [<c015d004>] (__handle_domain_irq) from [<c0101470>] (gic_handle_irq+0x50/0x9c) >>> [ 2.470135] [<c0101470>] (gic_handle_irq) from [<c010af14>] (__irq_svc+0x54/0x90) >>> [ 2.470141] Exception stack(0xee3d3c58 to 0xee3d3ca0) >>> [ 2.470148] 3c40: c0b1ef0c 0000000a >>> [ 2.470159] 3c60: 00000001 0000005c 0000016d 00000000 c0b4f7a4 00000006 00000000 0000005c >>> [ 2.470170] 3c80: 00000006 c0b671e8 60000013 ee3d3ca8 c0398e08 c015b830 60000013 ffffffff >>> [ 2.470183] [<c010af14>] (__irq_svc) from [<c015b830>] (console_unlock+0x560/0x628) >>> [ 2.470196] [<c015b830>] (console_unlock) from [<c015c1b0>] (vprintk_emit+0x1fc/0x508) >>> [ 2.470211] [<c015c1b0>] (vprintk_emit) from [<c03ed21c>] (dev_vprintk_emit+0xf8/0x198) >>> [ 2.470224] [<c03ed21c>] (dev_vprintk_emit) from [<c03ed2d8>] (dev_printk_emit+0x1c/0x2c) >>> [ 2.470235] [<c03ed2d8>] (dev_printk_emit) from [<c03ed334>] (__dev_printk+0x4c/0x70) >>> [ 2.470246] [<c03ed334>] (__dev_printk) from [<c03ed390>] (_dev_info+0x38/0x48) >>> [ 2.470258] [<c03ed390>] (_dev_info) from [<c045a7a4>] (usb_new_device+0xe8/0x3d0) >>> [ 2.470270] [<c045a7a4>] (usb_new_device) from [<c045bc20>] (hub_event+0x760/0xff4) >>> [ 2.470289] [<c045bc20>] (hub_event) from [<c012ff68>] (process_one_work+0x120/0x328) >>> [ 2.470304] [<c012ff68>] (process_one_work) from [<c01301d4>] (worker_thread+0x2c/0x4ac) >>> [ 2.470321] [<c01301d4>] (worker_thread) from [<c01353a4>] (kthread+0xd8/0xf4) >>> [ 2.470335] [<c01353a4>] (kthread) from [<c0107978 >>> >>> I'm checking this.. >>> >>> Best Regards, >>> Jaehoon Chung >>> >>>> >>>> Hi Jaehoon, >>>> >>>> How about this? >>>> >>>>> >>>>> Best Regards, >>>>> - Seung-Woo Kim >>>>> >>>>>> >>>>>> --- a/drivers/mmc/host/dw_mmc.c >>>>>> +++ b/drivers/mmc/host/dw_mmc.c >>>>>> @@ -2474,7 +2474,8 @@ static irqreturn_t dw_mci_interrupt(int irq, void >>>>>> *dev_id) >>>>>> mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_TI | >>>>>> >>>>>> SDMMC_IDMAC_INT_RI); >>>>>> mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_NI); >>>>>> - host->dma_ops->complete((void *)host); >>>>>> + if (!test_bit(EVENT_DATA_ERROR, >>>>>> &host->pending_events)) >>>>>> + host->dma_ops->complete((void *)host); >>>>>> } >>>>>> } else { >>>>>> pending = mci_readl(host, IDSTS); >>>>>> @@ -2482,7 +2483,8 @@ static irqreturn_t dw_mci_interrupt(int irq, void >>>>>> *dev_id) >>>>>> mci_writel(host, IDSTS, SDMMC_IDMAC_INT_TI | >>>>>> >>>>>> SDMMC_IDMAC_INT_RI); >>>>>> mci_writel(host, IDSTS, SDMMC_IDMAC_INT_NI); >>>>>> - host->dma_ops->complete((void *)host); >>>>>> + if (!test_bit(EVENT_DATA_ERROR, >>>>>> &host->pending_events)) >>>>>> + host->dma_ops->complete((void *)host); >>>>>> } >>>>>> } >>>>>> >>>>>> >>>>>>> [size=128 bytes] >>>>>>> Modules linked in: >>>>>>> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.7.0-rc4 #26 >>>>>>> Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) >>>>>>> [<c0112b4c>] (unwind_backtrace) from [<c010d888>] (show_stack+0x20/0x24) >>>>>>> [<c010d888>] (show_stack) from [<c03fab0c>] (dump_stack+0x80/0x94) >>>>>>> [<c03fab0c>] (dump_stack) from [<c0123548>] (__warn+0xf8/0x110) >>>>>>> [<c0123548>] (__warn) from [<c01235a8>] (warn_slowpath_fmt+0x48/0x50) >>>>>>> [<c01235a8>] (warn_slowpath_fmt) from [<c042ac90>] (check_unmap+0x7bc/0xb38) >>>>>>> [<c042ac90>] (check_unmap) from [<c042b25c>] (debug_dma_unmap_sg+0x118/0x148) >>>>>>> [<c042b25c>] (debug_dma_unmap_sg) from [<c077512c>] (dw_mci_dma_cleanup+0x7c/0xb8) >>>>>>> [<c077512c>] (dw_mci_dma_cleanup) from [<c0773f24>] (dw_mci_stop_dma+0x40/0x50) >>>>>>> [<c0773f24>] (dw_mci_stop_dma) from [<c0777d04>] (dw_mci_tasklet_func+0x130/0x3b4) >>>>>>> [<c0777d04>] (dw_mci_tasklet_func) from [<c0129760>] (tasklet_action+0xb4/0x150) >>>>>>> [<c0129760>] (tasklet_action) from [<c0101674>] (__do_softirq+0xe4/0x3cc) >>>>>>> [<c0101674>] (__do_softirq) from [<c0129030>] (irq_exit+0xd0/0x10c) >>>>>>> [<c0129030>] (irq_exit) from [<c01778a0>] (__handle_domain_irq+0x90/0xfc) >>>>>>> [<c01778a0>] (__handle_domain_irq) from [<c0101548>] (gic_handle_irq+0x64/0xa8) >>>>>>> [<c0101548>] (gic_handle_irq) from [<c010e3d4>] (__irq_svc+0x54/0x90) >>>>>>> Exception stack(0xc1101ef8 to 0xc1101f40) >>>>>>> 1ee0: 00000001 00000000 >>>>>>> 1f00: 00000000 c011b600 c1100000 c110753c 00000000 c11c3984 c11074d4 c1107548 >>>>>>> 1f20: 00000000 c1101f54 c1101f58 c1101f48 c010a1fc c010a200 60000013 ffffffff >>>>>>> [<c010e3d4>] (__irq_svc) from [<c010a200>] (arch_cpu_idle+0x48/0x4c) >>>>>>> [<c010a200>] (arch_cpu_idle) from [<c01669d8>] (default_idle_call+0x30/0x3c) >>>>>>> [<c01669d8>] (default_idle_call) from [<c0166d3c>] (cpu_startup_entry+0x358/0x3b4) >>>>>>> [<c0166d3c>] (cpu_startup_entry) from [<c0aa6ab8>] (rest_init+0x94/0x98) >>>>>>> [<c0aa6ab8>] (rest_init) from [<c1000d58>] (start_kernel+0x3a4/0x3b0) >>>>>>> [<c1000d58>] (start_kernel) from [<4000807c>] (0x4000807c) >>>>>>> ---[ end trace 256f83eed365daf0 ]--- >>>>>>> >>>>>>> The warning occurs because after complete callback function, >>>>>>> dw_mci_dmac_complete_dma() is called, then dw_mci_stop_dma() is called >>>>>>> again. So it causes dma_unmap_sg() is called twice for same sg. It >>>>>>> occurs during clock setting at booting time. >>>>>>> >>>>>>> Simply, clearing host->using_dma flag on dw_mci_dmac_complete_dma() and >>>>>>> dw_mci_stop_dma() like following fixes the issue, but I am not sure >>>>>>> this approach is proper. >>>>>>> --- >>>>>>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c >>>>>>> index 2cc6123..a71c94b 100644 >>>>>>> --- a/drivers/mmc/host/dw_mmc.c >>>>>>> +++ b/drivers/mmc/host/dw_mmc.c >>>>>>> @@ -388,6 +388,7 @@ static void dw_mci_stop_dma(struct dw_mci *host) >>>>>>> if (host->using_dma) { >>>>>>> host->dma_ops->stop(host); >>>>>>> host->dma_ops->cleanup(host); >>>>>>> + host->using_dma = 0; >>>>>>> } >>>>>>> >>>>>>> /* Data transfer was stopped by the interrupt handler */ >>>>>>> @@ -455,6 +456,7 @@ static void dw_mci_dmac_complete_dma(void *arg) >>>>>>> DMA_FROM_DEVICE); >>>>>>> >>>>>>> host->dma_ops->cleanup(host); >>>>>>> + host->using_dma = 0; >>>>>>> >>>>>>> /* >>>>>>> * If the card was removed, data will be NULL. No point in trying to >>>>>>> @@ -943,8 +945,6 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data) >>>>>>> int sg_len; >>>>>>> u32 temp; >>>>>>> >>>>>>> - host->using_dma = 0; >>>>>>> - >>>>>>> /* If we don't have a channel, we can't do DMA */ >>>>>>> if (!host->use_dma) >>>>>>> return -ENODEV; >>>>>>> --- >>>>>>> >>>>>>> Best Regards, >>>>>>> - Seung-Woo Kim >>>>>>> >>>>>>> -- >>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in >>>>>>> the body of a message to majordomo@vger.kernel.org >>>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Best Regards >>>>>> Shawn Lin >>>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>> >>> >>> >>> >> >> > > > >
-- Best Regards Shawn Lin
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