Hi Tuomas, It seems to produce this problem when wifi is enabled. In case of WiFi, used the sdio_bus_register in sdio_bus.c. Then i think right that "shutdown callback function" is existed in WiFi driver. And need to use the sdio_bus_shutdown, not mmc_bus_shutdown. sdio is used sdio_driver and mmc/sd is used mmc_driver. I think that didnt consider this point. Maybe need to check whether drv is NULL or not. If i misunderstood something, let me know. Best Regards, Jaehoon Chung On 07/01/2013 08:40 PM, Tuomas Tynkkynen wrote: > Hi, > > On next-20130628 I get the following Oops during reboot: > [ 89.814921] Unable to handle kernel NULL pointer dereference at virtual address 0000004c > [ 89.824208] pgd = ecd54000 > [ 89.827276] [0000004c] *pgd=00000000 > [ 89.831340] Internal error: Oops: 5 [#1] PREEMPT SMP ARM > > [<c040b244>] (mmc_bus_shutdown+0x24/0x70) from [<c032aa6c>] (device_shutdown+0x44/0x19c) > [<c032aa6c>] (device_shutdown+0x44/0x19c) from [<c0054508>] (kernel_restart_prepare+0x44/0x48) > [<c0054508>] (kernel_restart_prepare+0x44/0x48) from [<c0054528>] (kernel_restart+0x1c/0x70) > [<c0054528>] (kernel_restart+0x1c/0x70) from [<c0054704>] (SyS_reboot+0x168/0x1f0) > [<c0054704>] (SyS_reboot+0x168/0x1f0) from [<c000ed00>] (ret_fast_syscall+0x0/0x30) > > The corresponding line in mmc_bus_shutdown is "drv->shutdown(card);" > and 'drv' seems indeed to be NULL. > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
