Re: [PATCH] powerpc/bpf: Enable bpf_probe_read{, str}() on powerpc again

From: Petr Mladek
Date: Thu May 28 2020 - 05:13:56 EST


On Thu 2020-05-28 11:03:43, Michael Ellerman wrote:
> Petr Mladek <pmladek@xxxxxxxx> writes:
> > The commit 0ebeea8ca8a4d1d453a ("bpf: Restrict bpf_probe_read{, str}() only
> > to archs where they work") caused that bpf_probe_read{, str}() functions
> > were not longer available on architectures where the same logical address
> > might have different content in kernel and user memory mapping. These
> > architectures should use probe_read_{user,kernel}_str helpers.
> >
> > For backward compatibility, the problematic functions are still available
> > on architectures where the user and kernel address spaces are not
> > overlapping. This is defined CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
> >
> > At the moment, these backward compatible functions are enabled only
> > on x86_64, arm, and arm64. Let's do it also on powerpc that has
> > the non overlapping address space as well.
> >
> > Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
>
> This seems like it should have a Fixes: tag and go into v5.7?

Good point:

Fixes: commit 0ebeea8ca8a4d1d4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work")

And yes, it should ideally go into v5.7 either directly or via stable.

Should I resend the patch with Fixes and
Cc: stable@xxxxxxxxxxxxxxx #v45.7 lines, please?

Best Regards,
Petr