netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Masahiro Yamada <masahiroy@kernel.org>
Cc: "Alexei Starovoitov" <ast@kernel.org>,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	linux-kbuild@vger.kernel.org, "Michal Kubecek" <mkubecek@suse.cz>,
	linux-kernel@vger.kernel.org, "Andrii Nakryiko" <andriin@fb.com>,
	"Daniel Borkmann" <daniel@iogearbox.net>,
	"David S. Miller" <davem@davemloft.net>,
	"Jakub Kicinski" <kuba@kernel.org>,
	"John Fastabend" <john.fastabend@gmail.com>,
	"KP Singh" <kpsingh@chromium.org>,
	"Martin KaFai Lau" <kafai@fb.com>,
	"Sam Ravnborg" <sam@ravnborg.org>,
	"Song Liu" <songliubraving@fb.com>,
	"Valdis Kl ē tnieks" <valdis.kletnieks@vt.edu>,
	"Yonghong Song" <yhs@fb.com>
Subject: Re: [PATCH] bpfilter: allow to build bpfilter_umh as a module without static library
Date: Wed, 1 Jul 2020 10:46:09 -0700	[thread overview]
Message-ID: <20200701174609.mw5ovqe7d5o6ptel@ast-mbp.dhcp.thefacebook.com> (raw)
In-Reply-To: <20200701092644.762234-1-masahiroy@kernel.org>

On Wed, Jul 01, 2020 at 06:26:44PM +0900, Masahiro Yamada wrote:
> Originally, bpfilter_umh was linked with -static only when
> CONFIG_BPFILTER_UMH=y.
> 
> Commit 8a2cc0505cc4 ("bpfilter: use 'userprogs' syntax to build
> bpfilter_umh") silently, accidentally dropped the CONFIG_BPFILTER_UMH=y
> test in the Makefile. Revive it in order to link it dynamically when
> CONFIG_BPFILTER_UMH=m.
> 
> Since commit b1183b6dca3e ("bpfilter: check if $(CC) can link static
> libc in Kconfig"), the compiler must be capable of static linking to
> enable CONFIG_BPFILTER_UMH, but it requires more than needed.
> 
> To loosen the compiler requirement, I changed the dependency as follows:
> 
>     depends on CC_CAN_LINK
>     depends on m || CC_CAN_LINK_STATIC
> 
> If CONFIG_CC_CAN_LINK_STATIC in unset, CONFIG_BPFILTER_UMH is restricted
> to 'm' or 'n'.
> 
> In theory, CONFIG_CC_CAN_LINK is not required for CONFIG_BPFILTER_UMH=y,
> but I did not come up with a good way to describe it.
> 
> Fixes: 8a2cc0505cc4 ("bpfilter: use 'userprogs' syntax to build bpfilter_umh")
> Reported-by: Michal Kubecek <mkubecek@suse.cz>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

lgtm
Do you mind I'll take it into bpf-next tree?
Eric is working on a bunch of patches in this area. I'll take his set
into bpf-next as well and then can apply this patch.
Just to make sure there are no conflicts.

  parent reply	other threads:[~2020-07-01 17:46 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-01  9:26 [PATCH] bpfilter: allow to build bpfilter_umh as a module without static library Masahiro Yamada
2020-07-01 12:57 ` Michal Kubecek
2020-07-01 17:46 ` Alexei Starovoitov [this message]
2020-07-01 17:50   ` Masahiro Yamada
2020-07-14 19:39     ` Alexei Starovoitov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200701174609.mw5ovqe7d5o6ptel@ast-mbp.dhcp.thefacebook.com \
    --to=alexei.starovoitov@gmail.com \
    --cc=andriin@fb.com \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=john.fastabend@gmail.com \
    --cc=kafai@fb.com \
    --cc=kpsingh@chromium.org \
    --cc=kuba@kernel.org \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=masahiroy@kernel.org \
    --cc=mkubecek@suse.cz \
    --cc=netdev@vger.kernel.org \
    --cc=sam@ravnborg.org \
    --cc=songliubraving@fb.com \
    --cc=valdis.kletnieks@vt.edu \
    --cc=yhs@fb.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).