From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 C921A47F64; Fri, 2 Aug 2024 22:19:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722637194; cv=none; b=uI9lhhPp86h1EyLCq2svqF1Fc2rMs1kbfTI2aNmTUR84/FecGrvpTgEkaqdfnBbm8isA134Kc1dkIDz8exDpuO7gwLtVAu0Ge/Xyo4Y+GyNRtT2U+0Q88avlEEvgAQxpauIKgSffBDr5LtoGHzWttTbie8ykYcD+Un9szst7Vws= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722637194; c=relaxed/simple; bh=mcxSg+qGadL76KNrl2hpaR9JR+cq+JmpnzMW4vQqLJk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=h5U/9UnUuS0KSi2kZIPmIJ2QN2KtVVXOdGWPHtOqQbMjZbgMByJdk6dU5kzVGe9pcZrNBfrQn3Wwd6qxoqqe16RMEZTFcq8MSM93x0LAqNTsHQvvE3JdvafxN8o9yXqym8li9jAr5vrjMJHWvs4EUCx2o/w1B+0ZZRQbUY8Bs1A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=axS8BAGd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="axS8BAGd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EADC5C32782; Fri, 2 Aug 2024 22:19:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722637194; bh=mcxSg+qGadL76KNrl2hpaR9JR+cq+JmpnzMW4vQqLJk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=axS8BAGdIKBBiJOnu35QVEQ1ct0UdlZxaDkc6OsnMxIFpMVmuJPfSkjj7HisuhCTK LNgr5LvYCdNJYCe1iqm7wpR0fKl5FGLBsKLhE36Yq1rCWlh/8dfM8saGqJDDt0szrs gmbUTyrY3SlMT/dpkvlwBnRKtqmibUv29JjaHf3jSv9ryI1uK4XJrtdw1RwyAnD8JO dV6z+4pFx/BCgNdJYVurZMnTdmNhu0buBTKl7SZjLKKUL7KXYnkVSOk5lqiqpKUAQN /0l2LhhveEFRb64g28x/HUKtm/rT4dWcJLIehaLMv0x+td41hAYDTiONTQJFGtvAIa Ffyq+WDpzEQOw== Date: Fri, 2 Aug 2024 15:19:52 -0700 From: Nathan Chancellor To: "Gustavo A. R. Silva" Cc: kernel test robot , "Gustavo A. R. Silva" , llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev, LKML , Brian Cain , linux-hexagon@vger.kernel.org Subject: Re: [gustavoars:testing/wfamnae-next20240729-cbc-2 11/18] include/rdma/uverbs_ioctl.h:643:15: error: static assertion failed due to requirement '__builtin_offsetof(struct uverbs_attr_bundle, attrs) == sizeof(struct uverbs_attr_bundle_hdr)': struct member likely outside of struct_group_tagged() Message-ID: <20240802221952.GA737452@thelio-3990X> References: <202408011956.wscyBwq6-lkp@intel.com> <138da3e5-0e24-41a6-bb35-df5d07045eb3@embeddedor.com> <20240801190813.GC122261@thelio-3990X> <20240801221427.GA3773553@thelio-3990X> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Thu, Aug 01, 2024 at 04:35:59PM -0600, Gustavo A. R. Silva wrote: > > > On 01/08/24 16:14, Nathan Chancellor wrote: > > On Thu, Aug 01, 2024 at 02:17:50PM -0600, Gustavo A. R. Silva wrote: > > > > > > > > > On 01/08/24 13:08, Nathan Chancellor wrote: > > > > On Thu, Aug 01, 2024 at 06:47:58AM -0600, Gustavo A. R. Silva wrote: > > > > > > > > > > > > > > > On 01/08/24 05:35, kernel test robot wrote: > > > > > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git testing/wfamnae-next20240729-cbc-2 > > > > > > head: df15c862c1b93b6e1f6c90b0d7971f7a6ad66751 > > > > > > commit: e7cd9f429a852fb7e37a706c7d08fc36e7863e06 [11/18] RDMA/uverbs: Use static_assert() to check struct sizes > > > > > > config: hexagon-randconfig-001-20240801 (https://download.01.org/0day-ci/archive/20240801/202408011956.wscyBwq6-lkp@intel.com/config) > > > > > > compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 430b90f04533b099d788db2668176038be38c53b) > > > > > > > > > > > > > > > Clang 20.0.0?? (thinkingface) > > > > > > > > Indeed, Clang 19 branched and main is now 20 :) > > > > > > > > https://github.com/llvm/llvm-project/commit/8f701b5df0adb3a2960d78ca2ad9cf53f39ba2fe > > > > > > Yeah, but is that a stable release? > > > > No, but the Intel folks have tested tip of tree LLVM against the kernel > > for us for a few years now to try and catch issues such as this. > > Oh, I see, fine. :) > > > > > > BTW, I don't see GCC reporting the same problem below: > > > > Hexagon does not have a GCC backend anymore so it is not going to be > > possible to do an exact A/B comparison with this configuration but... > > > > > > > > > > include/rdma/uverbs_ioctl.h:643:15: error: static assertion failed due to requirement '__builtin_offsetof(struct uverbs_attr_bundle, attrs) == sizeof(struct uverbs_attr_bundle_hdr)': struct member likely outside of struct_group_tagged() > > > > > > 643 | static_assert(offsetof(struct uverbs_attr_bundle, attrs) == sizeof(struct uverbs_attr_bundle_hdr), > > > > > > | ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > 644 | "struct member likely outside of struct_group_tagged()"); > > > > > > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > include/linux/stddef.h:16:32: note: expanded from macro 'offsetof' > > > > > > 16 | #define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER) > > > > > > | ^ > > > > > > include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert' > > > > > > 77 | #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) > > > > > > | ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert' > > > > > > 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) > > > > > > | ^~~~ > > > > > > include/rdma/uverbs_ioctl.h:643:58: note: expression evaluates to '56 == 52' > > > > This seems to give some indication that perhaps there may be some > > architecture specific here with padding maybe? I seem to recall ARM OABI > > having something similar. Adding the Hexagon folks/list to get some more > > clarification. Full warning and context: > > > > https://lore.kernel.org/202408011956.wscyBwq6-lkp@intel.com/ > > > > The problematic section preprocessed since sometimes the macros > > obfuscate things: > > > > struct uverbs_attr_bundle { > > union { > > struct { > > struct ib_udata driver_udata; > > struct ib_udata ucore; > > struct ib_uverbs_file *ufile; > > struct ib_ucontext *context; > > struct ib_uobject *uobject; > > unsigned long attr_present[(((UVERBS_API_ATTR_BKEY_LEN) + > > ((sizeof(long) * 8)) - 1) / > > ((sizeof(long) * 8)))]; > > }; > > struct uverbs_attr_bundle_hdr { > > struct ib_udata driver_udata; > > struct ib_udata ucore; > > struct ib_uverbs_file *ufile; > > struct ib_ucontext *context; > > struct ib_uobject *uobject; > > unsigned long attr_present[(((UVERBS_API_ATTR_BKEY_LEN) + > > ((sizeof(long) * 8)) - 1) / > > ((sizeof(long) * 8)))]; > > } hdr; > > }; > > > > struct uverbs_attr attrs[]; > > }; > > _Static_assert(__builtin_offsetof(struct uverbs_attr_bundle, attrs) == > > sizeof(struct uverbs_attr_bundle_hdr), > > "struct member likely outside of struct_group_tagged()"); > > > > FWIW, I see this with all versions of Clang that the kernel supports > > with this configuration. > > I don't have access to a Clang compiler right now; I wonder if you could > help me get the output of this command: > > pahole -C uverbs_attr_bundle drivers/infiniband/core/rdma_core.o We disabled CONFIG_DEBUG_INFO_BTF for Hexagon because elfutils does not support Hexagon relocations but this is built-in for this configuration so I removed that limitation and ended up with: $ pahole -C uverbs_attr_bundle vmlinux struct uverbs_attr_bundle { union { struct { struct ib_udata driver_udata; /* 0 16 */ struct ib_udata ucore; /* 16 16 */ struct ib_uverbs_file * ufile; /* 32 4 */ struct ib_ucontext * context; /* 36 4 */ struct ib_uobject * uobject; /* 40 4 */ unsigned long attr_present[2]; /* 44 8 */ }; /* 0 52 */ struct uverbs_attr_bundle_hdr hdr; /* 0 52 */ }; /* 0 52 */ /* XXX 4 bytes hole, try to pack */ union { struct { struct ib_udata driver_udata; /* 0 16 */ struct ib_udata ucore; /* 16 16 */ struct ib_uverbs_file * ufile; /* 32 4 */ struct ib_ucontext * context; /* 36 4 */ struct ib_uobject * uobject; /* 40 4 */ unsigned long attr_present[2]; /* 44 8 */ }; /* 0 52 */ struct uverbs_attr_bundle_hdr hdr; /* 0 52 */ }; struct uverbs_attr attrs[]; /* 56 0 */ /* size: 56, cachelines: 1, members: 2 */ /* sum members: 52, holes: 1, sum holes: 4 */ /* last cacheline: 56 bytes */ }; If you want any other information or want me to test anything, I am more than happy to do so. Cheers, Nathan > > > > > > 643 | static_assert(offsetof(struct uverbs_attr_bundle, attrs) == sizeof(struct uverbs_attr_bundle_hdr), > > > > > > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > 644 | "struct member likely outside of struct_group_tagged()"); > > > > > > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > include/linux/build_bug.h:77:50: note: expanded from macro 'static_assert' > > > > > > 77 | #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) > > > > > > | ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~ > > > > > > include/linux/build_bug.h:78:56: note: expanded from macro '__static_assert' > > > > > > 78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) > > > > > > | ^~~~ > > > > > > 7 warnings and 1 error generated. > > > > > > > > > > > > > > > > > > vim +643 include/rdma/uverbs_ioctl.h > > > > > > > > > > > > 630 > > > > > > 631 struct uverbs_attr_bundle { > > > > > > 632 /* New members MUST be added within the struct_group() macro below. */ > > > > > > 633 struct_group_tagged(uverbs_attr_bundle_hdr, hdr, > > > > > > 634 struct ib_udata driver_udata; > > > > > > 635 struct ib_udata ucore; > > > > > > 636 struct ib_uverbs_file *ufile; > > > > > > 637 struct ib_ucontext *context; > > > > > > 638 struct ib_uobject *uobject; > > > > > > 639 DECLARE_BITMAP(attr_present, UVERBS_API_ATTR_BKEY_LEN); > > > > > > 640 ); > > > > > > 641 struct uverbs_attr attrs[]; > > > > > > 642 }; > > > > > > > 643 static_assert(offsetof(struct uverbs_attr_bundle, attrs) == sizeof(struct uverbs_attr_bundle_hdr), > > > > > > 644 "struct member likely outside of struct_group_tagged()"); > > > > > > 645 > > > > > > > > > > > > > > > > > Thanks > > > -- > > > Gustavo