On Wed, May 01, 2019 at 11:54:56AM -0600, Raul E Rangel wrote: > I am running into a kernel panic. A task gets stuck for more than 120 > seconds. I keep seeing blkdev_close in the stack trace, so maybe I'm not > calling something correctly? > > Here is the panic: https://privatebin.net/?8ec48c1547d19975#dq/h189w5jmTlbMKKAwZjUr4bhm7Q2AgvGdRqc5BxAc= > > I sometimes see the following: > [ 547.943974] udevd[144]: seq 2350 '/devices/pci0000:00/0000:00:14.7/mmc_host/mmc0/mmc0:0001/block/mmcblk0/mmcblk0p1' is taking a long time > > I was getting the kernel panic on a 4.14 kernel: https://chromium.googlesource.com/chromiumos/third_party/kernel/+/f3dc032faf4d074f20ada437e2d081a28ac699da/drivers/mmc/host > So I'm guessing I'm missing an upstream fix. > So I tried these patches on the 5.1 with the memory leak patch applied: https://patchwork.kernel.org/patch/10927541/ Everything works as expected: mmc0: new high speed SDHC card at address 0001 mmcblk0: mmc0:0001 00000 7.41 GiB mmcblk0: p1 p2 mmc0: card status changed during reset mmc0: card was removed during reset mmc0: tried to HW reset card, got error -123 print_req_error: I/O error, dev mmcblk0, sector 2072 flags 80700 print_req_error: I/O error, dev mmcblk0, sector 2073 flags 80700 mmc0: card 0001 removed mmc0: new high speed SDHC card at address 0001 mmcblk0: mmc0:0001 00000 7.41 GiB mmcblk0: p1 p2 mmc0: card status changed during reset mmc0: card was removed during reset mmc0: tried to HW reset card, got error -123 print_req_error: I/O error, dev mmcblk0, sector 12584832 flags 80700 print_req_error: I/O error, dev mmcblk0, sector 12584833 flags 80700 mmc0: card 0001 removed Buffer I/O error on dev mmcblk0p2, logical block 369904, async page read mmc0: new high speed SDHC card at address 0001 mmcblk0: mmc0:0001 00000 7.41 GiB mmcblk0: p1 p2 mmc0: card 0001 removed I also ran another test. Using the DUT with a GPIO to randomly toggle the CD pin I was able to get 4k+ iterations without any problems. So I think the patches are good. --- Iteration 4506 ---- Disconnecting card [ 7444.370169] mmc0: card 0001 removed Connecting Card and sleeping for 0.31476s [ 7444.682177] mmc0: new high speed SDHC card at address 0001 [ 7444.719038] mmcblk0: mmc0:0001 00000 7.41 GiB [ 7444.727375] mmcblk0: p1 p2 Card Disconnected [ 7444.831896] mmc0: Card removed during transfer! [ 7444.831914] mmc0: Resetting controller. --- Iteration 4507 ---- Connecting Card and sleeping for 0.30259s [ 7445.033649] mmc0: card 0001 removed Card Disconnected [ 7445.307008] mmc0: error -123 whilst initialising SD card --- Iteration 4508 ---- Connecting Card and sleeping for 0.24827s Card Disconnected [ 7445.716033] mmc0: Card removed during transfer! [ 7445.716052] mmc0: Resetting controller. [ 7445.716489] mmc0: error -123 whilst initialising SD card --- Iteration 4509 ---- Connecting Card and sleeping for 0.14132s Card Disconnected --- Iteration 4510 ---- Connecting Card and sleeping for 0.26001s Card Disconnected [ 7446.436079] mmc0: error -123 whilst initialising SD card Connecting card to verify if it died [ 7446.906804] mmc0: new high speed SDHC card at address 0001 [ 7446.933631] mmcblk0: mmc0:0001 00000 7.41 GiB [ 7446.949224] mmcblk0: p1 p2 SDHC still functional Should I send the patches out again without the RFC tag? I'll keep trying to track down the hung task I was seeing on 4.14. But I don't think that's related to these patches. I might just end up backporting the blk-mq patches to our 4.14 branch since I suspect that fixes it. Thanks, Raul
