[PATCH net-next v2 0/3] compiler_types: add Endianness-dependent __counted_by_{le,be}

From: Alexander Lobakin <aleksander.lobakin@intel.com>
To: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>,
	Kees Cook <keescook@chromium.org>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	Nathan Chancellor <nathan@kernel.org>,
	Simon Horman <horms@kernel.org>,
	nex.sw.ncis.osdt.itp.upstreaming@intel.com,
	intel-wired-lan@lists.osuosl.org,
	linux-hardening@vger.kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH net-next v2 0/3] compiler_types: add Endianness-dependent __counted_by_{le,be}
Date: Wed, 27 Mar 2024 15:22:38 +0100	[thread overview]
Message-ID: <20240327142241.1745989-1-aleksander.lobakin@intel.com> (raw)

Some structures contain flexible arrays at the end and the counter for
them, but the counter has explicit Endianness and thus __counted_by()
can't be used directly.

To increase test coverage for potential problems without breaking
anything, introduce __counted_by_{le,be} defined depending on platform's
Endianness to either __counted_by() when applicable or noop otherwise.
The first user will be virtchnl2.h from idpf just as example with 9 flex
structures having Little Endian counters.

Maybe it would be a good idea to introduce such attributes on compiler
level if possible, but for now let's stop on what we have.

Alexander Lobakin (3):
  compiler_types: add Endianness-dependent __counted_by_{le,be}
  idpf: make virtchnl2.h self-contained
  idpf: sprinkle __counted_by{,_le}() in the virtchnl2 header

 Documentation/conf.py                       |  2 ++
 scripts/kernel-doc                          |  1 +
 include/linux/compiler_types.h              | 11 ++++++++++
 drivers/net/ethernet/intel/idpf/idpf_txrx.h |  2 ++
 drivers/net/ethernet/intel/idpf/virtchnl2.h | 24 ++++++++++-----------
 5 files changed, 28 insertions(+), 12 deletions(-)

---
From v1[0]:
* fix compilation of #2 (Jakub);
* pick Acked-bys (Gustavo).

From RFC[1]:

* teach kdoc new attributes (Simon, Kees);
* add Acked-by (Kees);
* fix a couple typos;
* send to net-next (Kees).

[0] https://lore.kernel.org/netdev/20240326164116.645718-1-aleksander.lobakin@intel.com
[1] https://lore.kernel.org/netdev/20240318130354.2713265-1-aleksander.lobakin@intel.com
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