On 28/09/20 8:02 am, Coly Li wrote: > On 2020/9/28 11:15, Coly Li wrote: >> On 2020/9/28 04:29, Vicente Bergas wrote: >>> Hi, >>> since recently the rk3399-gru-kevin is reporting the trace below. >>> The issue has been uncovered by >>> b35fd7422c2f8e04496f5a770bd4e1a205414b3f >>> block: check queue's limits.discard_granularity in >>> __blkdev_issue_discard() >> >> Hi Vicente, >> >> Thanks for the information. It seems the device with f2fs declares to >> support DISCARD but don't initialize discard_granularity for its queue. >> >> Can I know which block driver is under f2fs ? > > Maybe it is the mmc driver. A zero value discard_granularity is from the > following commit: > > commit e056a1b5b67b4e4bfad00bf143ab14f634777705 > Author: Adrian Hunter <adrian.hunter@xxxxxxxxx> > Date: Tue Jun 28 17:16:02 2011 +0300 > > mmc: queue: let host controllers specify maximum discard timeout > > Some host controllers will not operate without a hardware > timeout that is limited in value. However large discards > require large timeouts, so there needs to be a way to > specify the maximum discard size. > > A host controller driver may now specify the maximum discard > timeout possible so that max_discard_sectors can be calculated. > > However, for eMMC when the High Capacity Erase Group Size > is not in use, the timeout calculation depends on clock > rate which may change. For that case Preferred Erase Size > is used instead. > > Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> > Signed-off-by: Chris Ball <cjb@xxxxxxxxxx> > > > Hi Adrian and Chris, > > I am not familiar with mmc driver, therefore I won't provide a quick fix > like this (which might probably wrong), > --- a/drivers/mmc/core/queue.c > +++ b/drivers/mmc/core/queue.c > @@ -190,7 +190,7 @@ static void mmc_queue_setup_discard(struct > request_queue *q, > q->limits.discard_granularity = card->pref_erase << 9; > /* granularity must not be greater than max. discard */ > if (card->pref_erase > max_discard) > - q->limits.discard_granularity = 0; > + q->limits.discard_granularity = SECTOR_SIZE; > if (mmc_can_secure_erase_trim(card)) > blk_queue_flag_set(QUEUE_FLAG_SECERASE, q); > } > > > It is improper for a device driver to declare to support DISCARD but set > queue's discard_granularity as 0. > > Could you please to take a look for mmc_queue_setup_discard() ? This should be OK. > > Thanks in advance. > > Coly Li > > >> >>> >>> WARNING: CPU: 0 PID: 135 at __blkdev_issue_discard+0x200/0x294 >>> CPU: 0 PID: 135 Comm: f2fs_discard-17 Not tainted 5.9.0-rc6 #1 >>> Hardware name: Google Kevin (DT) >>> pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--) >>> pc : __blkdev_issue_discard+0x200/0x294 >>> lr : __blkdev_issue_discard+0x54/0x294 >>> sp : ffff800011dd3b10 >>> x29: ffff800011dd3b10 x28: 0000000000000000 x27: ffff800011dd3cc4 x26: >>> ffff800011dd3e18 x25: 000000000004e69b x24: 0000000000000c40 x23: >>> ffff0000f1deaaf0 x22: ffff0000f2849200 x21: 00000000002734d8 x20: >>> 0000000000000008 x19: 0000000000000000 x18: 0000000000000000 x17: >>> 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: >>> 0000000000000394 x13: 0000000000000000 x12: 0000000000000000 x11: >>> 0000000000000000 x10: 00000000000008b0 x9 : ffff800011dd3cb0 x8 : >>> 000000000004e69b x7 : 0000000000000000 x6 : ffff0000f1926400 x5 : >>> ffff0000f1940800 x4 : 0000000000000000 x3 : 0000000000000c40 x2 : >>> 0000000000000008 x1 : 00000000002734d8 x0 : 0000000000000000 Call trace: >>> __blkdev_issue_discard+0x200/0x294 >>> __submit_discard_cmd+0x128/0x374 >>> __issue_discard_cmd_orderly+0x188/0x244 >>> __issue_discard_cmd+0x2e8/0x33c >>> issue_discard_thread+0xe8/0x2f0 >>> kthread+0x11c/0x120 >>> ret_from_fork+0x10/0x1c >>> ---[ end trace e4c8023d33dfe77a ]--- >>> mmcblk1p2: Error: discard_granularity is 0. >>> mmcblk1p2: Error: discard_granularity is 0. >>> <last message repeated multiple times> >> >
