[PATCH 0/3] bpf: add boot parameters for sysctl knobs

[PATCH 0/3] bpf: add boot parameters for sysctl knobs

[Eugene Syromiatnikov]

Hello.

This patch set adds ability to set default values for
kernel.unprivileged_bpf_disable, net.core.bpf_jit_harden,
net.core.bpf_jit_kallsyms sysctl knobs as well as option to override
them via a boot-time kernel parameter.

Eugene Syromiatnikov (3):
  bpf: add ability to configure unprivileged BPF via boot-time parameter
  bpf: add ability to configure BPF JIT hardening via boot-time
    parameter
  bpf: add ability to configure BPF JIT kallsyms export at the boot time

 Documentation/admin-guide/kernel-parameters.txt | 28 ++++++++
 init/Kconfig                                    | 90 +++++++++++++++++++++++++
 kernel/bpf/core.c                               | 31 +++++++++
 kernel/bpf/syscall.c                            | 16 +++++
 4 files changed, 165 insertions(+)

-- 
2.1.4

Re: [PATCH 0/3] bpf: add boot parameters for sysctl knobs

[Alexei Starovoitov]

On Mon, May 21, 2018 at 02:29:30PM +0200, Eugene Syromiatnikov wrote:
> Hello.
> 
> This patch set adds ability to set default values for
> kernel.unprivileged_bpf_disable, net.core.bpf_jit_harden,
> net.core.bpf_jit_kallsyms sysctl knobs as well as option to override
> them via a boot-time kernel parameter.

Commits log not only should explain 'what' is being done by the patch,
but 'why' as well.

Re: [PATCH 0/3] bpf: add boot parameters for sysctl knobs

[Eugene Syromiatnikov]

On Mon, May 21, 2018 at 11:58:13AM -0700, Alexei Starovoitov wrote:
> On Mon, May 21, 2018 at 02:29:30PM +0200, Eugene Syromiatnikov wrote:
> > Hello.
> > 
> > This patch set adds ability to set default values for
> > kernel.unprivileged_bpf_disable, net.core.bpf_jit_harden,
> > net.core.bpf_jit_kallsyms sysctl knobs as well as option to override
> > them via a boot-time kernel parameter.
> 
> Commits log not only should explain 'what' is being done by the patch,
> but 'why' as well.

Some BPF sysctl knobs affect the loading of BPF programs, and during
system boot/init stages these sysctls are not yet configured. A
concrete example is systemd, that has implemented loading of BPF
programs.

Thus, to allow controlling these setting at early boot, this patch set
adds the ability to change the default setting of these sysctl knobs
as well as option to override them via a boot-time kernel parameter
(in order to avoid rebuilding kernel each time a need of changing these
defaults arises).

The sysctl knobs in question are kernel.unprivileged_bpf_disable,
net.core.bpf_jit_harden, and net.core.bpf_jit_kallsyms.

Re: [PATCH 0/3] bpf: add boot parameters for sysctl knobs

[Jesper Dangaard Brouer]

On Wed, 23 May 2018 13:35:47 +0200
Eugene Syromiatnikov <esyr@redhat.com> wrote:

> On Mon, May 21, 2018 at 11:58:13AM -0700, Alexei Starovoitov wrote:
> > On Mon, May 21, 2018 at 02:29:30PM +0200, Eugene Syromiatnikov wrote:  
> > > Hello.
> > > 
> > > This patch set adds ability to set default values for
> > > kernel.unprivileged_bpf_disable, net.core.bpf_jit_harden,
> > > net.core.bpf_jit_kallsyms sysctl knobs as well as option to override
> > > them via a boot-time kernel parameter.  
> > 
> > Commits log not only should explain 'what' is being done by the patch,
> > but 'why' as well.  
> 
> Some BPF sysctl knobs affect the loading of BPF programs, and during
> system boot/init stages these sysctls are not yet configured. A
> concrete example is systemd, that has implemented loading of BPF
> programs.
> 
> Thus, to allow controlling these setting at early boot, this patch set
> adds the ability to change the default setting of these sysctl knobs
> as well as option to override them via a boot-time kernel parameter
> (in order to avoid rebuilding kernel each time a need of changing these
> defaults arises).
> 
> The sysctl knobs in question are kernel.unprivileged_bpf_disable,
> net.core.bpf_jit_harden, and net.core.bpf_jit_kallsyms.

Hi Eugene,

You have to resend the entire patchset with this explanation in the
cover-letter.  Your old patchset have been dropped from patchwork[1]
due to being marked with "Changes Requested".

Please remember to give it a "V2" tag and also specify which git tree
you are targeting[2], like [PATCH bpf-next V2].


[1] http://patchwork.ozlabs.org/project/netdev/list/?series=45617&state=%2a

[2] https://github.com/netoptimizer/linux/blob/bpf_doc10/Documentation/bpf/bpf_devel_QA.rst#q-how-do-i-indicate-which-tree-bpf-vs-bpf-next-my-patch-should-be-applied-to
-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer