Re: CONFIG_VMAP_STACK, on-stack struct, and wake_up_bit

From: Linus Torvalds
Date: Wed Oct 26 2016 - 17:30:55 EST


On Wed, Oct 26, 2016 at 2:01 PM, Bob Peterson <rpeterso@xxxxxxxxxx> wrote:
>
> Hm. It didn't even boot, at least on my amd box in the lab.
> I've made no attempt to debug this.

Hmm. Looks like a completely independent issue from the patch. Did you
try booting that machine without the patch?

> [ 2.378877] kernel BUG at arch/x86/mm/physaddr.c:26!

Ok, similar issue, I think - passing a non-1:1 address to __phys_addr().

But the call trace has nothing to do with gfs2 or the bitlocks:

> [ 2.504561] Call Trace:
> [ 2.507005] save_microcode_in_initrd_amd+0x31/0x106
> [ 2.513778] save_microcode_in_initrd+0x3c/0x45
> [ 2.526110] do_one_initcall+0x50/0x180
> [ 2.531756] ? set_debug_rodata+0x12/0x12
> [ 2.537573] kernel_init_freeable+0x194/0x230
> [ 2.543740] ? rest_init+0x80/0x80
> [ 2.548952] kernel_init+0xe/0x100
> [ 2.554164] ret_from_fork+0x25/0x30

I think this might be the

cont = __pa(container);

line in save_microcode_in_initrd_amd().

I see that Borislav is busy with some x86/microcode patches, I suspect
he already hit this. Adding Borislav to the cc.

Can you re-try without the AMD microcode driver for now? This seems to
be a separate issue from the gfs2 one.

Linus