On Wed, Feb 19, 2014 at 8:32 AM, Alexander Shiyan <shc_work@xxxxxxx> wrote: > During testing functions transfer_one(), stumbled upon an error. > I'm using kernel 3.13, so I had to apply a patch from upstream > (spi: core: Fix transfer failure when master->transfer_one returns positive value). > After applying all becomes normal with probing, but where did the error > "Unable to handle kernel NULL pointer dereference" ? > Did someone have similar bugs? > > Thanks. > > spi_master spi0: failed to transfer one message from queue: 1 > 74x164 spi0.1: Failed writing: 1 > 74x164: probe of spi0.1 failed with error 1 > Unable to handle kernel NULL pointer dereference at virtual address 00000020 > CAN device driver interface > pgd = c0024000 > [00000020] *pgd=00000000 > Internal error: Oops: 63c11805 [#1] PREEMPT ARM > CPU: 0 PID: 22 Comm: spi0 Not tainted 3.13.3 #1 > task: c396b260 ti: c396e000 task.ti: c396e000 > PC is at spi_pump_messages+0x150/0x194 Have you applied other patches from upstream? E.g. e120cc0dcf2880a4c5c0a6cb27b655600a1cfa1d introduced a NULL pointer dereference, with got fixed by 1f802f8249a0da536877842c43c7204064c4de8b. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html