Hi Doug, On Saturday 01 November 2014 at 13:50:16, Doug Anderson wrote: > Max, > > On Sat, Nov 1, 2014 at 7:03 AM, Max Schwarz <max.schwarz at online.de> wrote: > > Hi all, > > > > I'm getting an Oops during boot of 3.18-rc2 on my Radxa Rock. It only > > happens when a microSD card is inserted. > > > > Full boot log: https://gist.github.com/xqms/ff6fc22407e705c9986d > > My .config: https://gist.github.com/xqms/9f80f9f9601f85d399cf > > > > The issue seems to be in the dw-mmc driver. It seems that an IRQ is > > triggered before the host->slot[i] pointer is initialized, causing the > > fault in line 2066 of drivers/mmc/host/dw_mmc.c: > > > > static void dw_mci_work_routine_card(struct work_struct *work) > > { > > > > struct dw_mci *host = container_of(work, struct dw_mci, > > card_work); > > int i; > > > > for (i = 0; i < host->num_slots; i++) { > > > > struct dw_mci_slot *slot = host->slot[i]; > > struct mmc_host *mmc = slot->mmc; <-- FAULT > > struct mmc_request *mrq; > > Yup. Sounds familiar. See > <https://patchwork.kernel.org/patch/4829341/>. I later decided that I > hadn't thought through everything enough so I ended up dropping the > patch. There is definitely a race here and it's existed for a long > time, I just wasn't sure my patch was the right fix. Amazingly the > problem disappeared for me (not that I liked that as a fix). > > > A bisect ends at: > > > > commit 51da2240906cb94e8f6ba55e403b6206df6fb2dd > > Author: Yuvaraj CD <yuvaraj.cd at gmail.com> > > Date: Fri Aug 22 19:17:50 2014 +0530 > > > > mmc: dw_mmc: use mmc_regulator_get_supply to handle regulators > > > > This patch makes use of mmc_regulator_get_supply() to handle > > the vmmc and vqmmc regulators.Also it moves the code handling > > the these regulators to dw_mci_set_ios().It turned on the vmmc > > and vqmmc during MMC_POWER_UP and MMC_POWER_ON,and turned off > > during MMC_POWER_OFF. > > > > Signed-off-by: Yuvaraj Kumar C D <yuvaraj.cd at samsung.com> > > Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org> > > > > That seems a bit unrelated to me, but maybe it causes a different > > initialization order? > > > > I'm playing around with the initialization order myself, but I haven't > > managed to find a working configuration yet. Can somebody with MMC > > knowledge find the problem or point me into the right direction? > > For me the problem randomly came and then randomly disappeared. > Others working on the same kernel would see it, then they wouldn't. Okay thanks, good to know it's not just me. It appeared with 3.18 for me, so I thought it would be good to fix it for the next -rc. But if the bug is older and something is in the works to fix it, I'm satisfied ;-) > ...if you want a fix, try grabbing (5998ad0 mmc: dw_mmc: Remove old > card detect infrastructure) from linuxnext. That kills the work > routine. I also threw an "if (!slot)" in there just because I was > worried about the problem coming back and I figured that it was better > not to crash. Thanks, will try that. Cheers, Max
