Hi Niklas,
On Wed, Mar 29, 2017 at 12:40 AM, Niklas Söderlund
<niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> This fixes a race condition where the channel resources could be freed
> before the ISR had finished running resulting in a NULL pointer
> reference from the ISR.
>
> [ 167.148934] Unable to handle kernel NULL pointer dereference at virtual address 00000000
> [ 167.157051] pgd = ffff80003c641000
> [ 167.160449] [00000000] *pgd=000000007c507003, *pud=000000007c4ff003, *pmd=0000000000000000
> [ 167.168719] Internal error: Oops: 96000046 [#1] PREEMPT SMP
> [ 167.174289] Modules linked in:
> [ 167.177348] CPU: 3 PID: 10547 Comm: dma_ioctl Not tainted 4.11.0-rc1-00001-g8d92afddc2f6633a #73
> [ 167.186131] Hardware name: Renesas Salvator-X board based on r8a7795 (DT)
> [ 167.192917] task: ffff80003a411a00 task.stack: ffff80003bcd4000
> [ 167.198850] PC is at rcar_dmac_chan_prep_sg+0xe0/0x400
> [ 167.203985] LR is at rcar_dmac_chan_prep_sg+0x48/0x400
Do you have a test case to trigger this?
Thanks!
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
