From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3E738256C8B; Sat, 24 Jan 2026 11:47:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=150.107.74.76 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769255261; cv=none; b=XLdizPn8twrfq1eC2T3XNCM/Ap7W/yXnHv2ea9iIzja1bCi+T0xwRj6kIycbaAHeqrPksBYVyFJNphEhbYgTsjKBlNPiUopPzq7W46GOdETDTmFKeHH771xIdGIvRQqt0cxir6rD8ij3JtWtQNz0gO5NIh+j4engfmvvX70oP5A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769255261; c=relaxed/simple; bh=iincRLQN8qCEKPF7i86sLhdZ46a3U2mvDd0AhMq0rsc=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=o7zn4y1UO7BCGj9QrYlekMBLHS4pEIiX+8aWgEJDQSxAWK/uJ6VtiKKAFpjq1+X4/HBbCvwJWKZHrW3S5G4jtErfDcE6Q3WjgMHQlDqNrz+mfQADzXxcXeyU4rYcU78N7hlKVt6ncdIvnozlL/HxARm/Y2TUGXB61BO/3WpOkoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au; spf=pass smtp.mailfrom=canb.auug.org.au; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b=Wm5Pfs+A; arc=none smtp.client-ip=150.107.74.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=canb.auug.org.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=canb.auug.org.au header.i=@canb.auug.org.au header.b="Wm5Pfs+A" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canb.auug.org.au; s=202503; t=1769255253; bh=3sDVQWlad4FBCe1xSzGexS2jbHGDgA5u4eJ2uQ1LPuo=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Wm5Pfs+AW4MJZ8Dv2sQAudwO+Zj2AH7enMbXuNEGM/aE7E8O3s65fppMLawxU5lXB WNL9LKklmllJn7+ZnZqhCFvEuIGBo+trrtdmrUdC4NdQZQ2zxwmQeCyws0ykl7FWR7 yrFwGQICE7ObFuwrIpI42x5FIHOw6gSgQv9+1zfl5ZmZI3s1Mshes7QT7eqbIkDXyH 710BQY4/6TOntVXNQkRhvrQ0NeNv/M+XZTZB3VESh/ycvAIzEmWAQ3GJbTYpKm+gRY Lb6D2LhjGV2xbFZSlJiJnpN/7JYs1cvksOt2qljnKQ0Wlvmh3kQIWU8aER5XVcijtL ahHVX9RfYPX0g== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mail.ozlabs.org (Postfix) with ESMTPSA id 4dytMS5lKWz4wCJ; Sat, 24 Jan 2026 22:47:31 +1100 (AEDT) Date: Sat, 24 Jan 2026 22:46:35 +1100 From: Stephen Rothwell To: Jens Axboe Cc: Mark Brown , Linux Kernel Mailing List , Linux Next Mailing List Subject: Re: linux-next: build failure after merge of the block tree Message-ID: <20260124114635.10bff99f@canb.auug.org.au> In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-next@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/tg+SWH5ISw9R97voRA78AW2"; protocol="application/pgp-signature"; micalg=pgp-sha256 --Sig_/tg+SWH5ISw9R97voRA78AW2 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Jens, On Fri, 23 Jan 2026 11:06:43 -0700 Jens Axboe wrote: > > On 1/23/26 11:00 AM, Jens Axboe wrote: > > On 1/23/26 10:42 AM, Mark Brown wrote: =20 > >> Hi all, > >> > >> After merging the block tree, today's linux-next build (x86 allmodconf= ig) > >> failed like this: > >> > >> In file included from /tmp/next/build/include/linux/string.h:386, > >> from /tmp/next/build/include/linux/bitmap.h:13, > >> from /tmp/next/build/include/linux/cpumask.h:11, > >> from /tmp/next/build/arch/x86/include/asm/paravirt.h:= 21, > >> from /tmp/next/build/arch/x86/include/asm/cpuid/api.h= :57, > >> from /tmp/next/build/arch/x86/include/asm/processor.h= :19, > >> from /tmp/next/build/include/linux/sched.h:13, > >> from /tmp/next/build/include/linux/io_uring.h:5, > >> from /tmp/next/build/io_uring/bpf_filter.c:7: > >> In function 'fortify_memset_chk', > >> inlined from 'io_uring_populate_bpf_ctx' at /tmp/next/build/io_uri= ng/bpf_filter.c:33:2: > >> /tmp/next/build/include/linux/fortify-string.h:480:25: error: call to = '__write_overflow_field' declared with attribute warning: detected write be= yond size of field (1st parameter); maybe use struct_group()? [-Werror=3Dat= tribute-warning] > >> 480 | __write_overflow_field(p_size_field, s= ize); > >> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~= ~~~~ > >> cc1: all warnings being treated as errors > >> > >> Caused by commit > >> > >> f1e3672e49e2c (io_uring: add support for BPF filtering for opcode re= strictions) =20 > >=20 > > Huh, that am I missing here? The struct looks as follows: > >=20 > > struct io_uring_bpf_ctx { > > __u64 user_data; > > __u8 opcode; > > __u8 sqe_flags; > > __u8 pad[6]; > > union { > > __u64 resv[6]; > > struct { > > __u32 family; > > __u32 type; > > __u32 protocol; > > } socket; > > struct { > > __u64 flags; > > __u64 mode; > > __u64 resolve; > > } open; > > }; > > }; > >=20 > > and the offending line is: > >=20 > > memset(bctx->pad, 0, sizeof(bctx->pad) + sizeof(bctx->resv)); > >=20 > > which should clear from offset 10 (start of pad) for a total of 6 + 48 > > bytes, which is 54 bytes. The size of the struct is 64b. > >=20 > > I guess the part it doesn't like is that it thinks we're clearing the > > pad field, which would of course be way overwriting it. Guess we can do > > something ala: > >=20 > > memset((void *) bctx + offsetof(struct io_uring_bpf_ctx, pad), 0, > > sizeof(bctx->pad) + sizeof(bctx->resv)); > >=20 > > to make it happier. =20 >=20 > Folded that in and pushed it out, should be happy for you now. I wonder > if we have a helper for that... The origin warning did suggest using struct_group(). --=20 Cheers, Stephen Rothwell --Sig_/tg+SWH5ISw9R97voRA78AW2 Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEENIC96giZ81tWdLgKAVBC80lX0GwFAml0sRsACgkQAVBC80lX 0GyK7ggAj4F7G/F/DFZ+B1ml62CWWou/LvifNSGAtTiUR1rHNdYm7or/Hv3xfw05 99rlFRsQwHNTe9N2eoEXfu3jqUGpGHNuBhmSTFJtYDNb3Lenbosr31Eh1o9FjLc6 gfiKLjpB4v1ZVjqdCHTeufnbGEj/A90yttAc8j3fbtD+1GqAFDlVqx21I56HBgGq QBxTDyQDfs4BRtF/wbZUAxwFYe3PiKY/qe7uj65tC1bZ2Yq9q3+jCLIjYBuKYrYN 0naDEeUI2vnjzVRTBN9nPU8v78QWuFm0p71XyN8MVCme849gUCNLJ+iMiSuqgbkP J3MRiiXFG+EPx/j+cLm6crykF5rPOw== =pgrE -----END PGP SIGNATURE----- --Sig_/tg+SWH5ISw9R97voRA78AW2--