linux-stable/include/linux/elfnote.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_ELFNOTE_H
#define _LINUX_ELFNOTE_H
/*
* Helper macros to generate ELF Note structures, which are put into a
* PT_NOTE segment of the final vmlinux image. These are useful for
* including name-value pairs of metadata into the kernel binary (or
* modules?) for use by external programs.
*
* Each note has three parts: a name, a type and a desc. The name is
* intended to distinguish the note's originator, so it would be a
* company, project, subsystem, etc; it must be in a suitable form for
* use in a section name. The type is an integer which is used to tag
* the data, and is considered to be within the "name" namespace (so
* "FooCo"'s type 42 is distinct from "BarProj"'s type 42). The
* "desc" field is the actual data. There are no constraints on the
* desc field's contents, though typically they're fairly small.
*
* All notes from a given NAME are put into a section named
* .note.NAME. When the kernel image is finally linked, all the notes
* are packed into a single .notes section, which is mapped into the
* PT_NOTE segment. Because notes for a given name are grouped into
* the same section, they'll all be adjacent the output file.
*
* This file defines macros for both C and assembler use. Their
* syntax is slightly different, but they're semantically similar.
*
* See the ELF specification for more detail about ELF notes.
*/
#ifdef __ASSEMBLER__
/*
* Generate a structure with the same shape as Elf{32,64}_Nhdr (which
* turn out to be the same size and shape), followed by the name and
[PATCH] Translate asm version of ELFNOTE macro into preprocessor macro I've come across some problems with the assembly version of the ELFNOTE macro currently in -mm. (in x86-put-note-sections-into-a-pt_note-segment-in-vmlinux.patch) The first is that older gas does not support :varargs in .macro definitions (in my testing 2.17 does while 2.15 does not, I don't know when it became supported). The Changes file says binutils >= 2.12 so I think we need to avoid using it. There are no other uses in mainline or -mm. Old gas appears to just ignore it so you get "too many arguments" type errors. Secondly it seems that passing strings as arguments to assembler macros is broken without varargs. It looks like they get unquoted or each character is treated as a separate argument or something and this causes all manner of grief. I think this is because of the use of -traditional when compiling assembly files. Therefore I have translated the assembler macro into a pre-processor macro. I added the desctype as a separate argument instead of including it with the descdata as the previous version did since -traditional means the ELFNOTE definition after the #else needs to have the same number of arguments (I think so anyway, the -traditional CPP semantics are pretty fscking strange!). With this patch I am able to define elfnotes in assembly like this with both old and new assemblers. ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz, "linux") ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz, "2.6") ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz, "xen-3.0") ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long, __PAGE_OFFSET) Which seems reasonable enough. Signed-off-by: Ian Campbell <ian.campbell@xensource.com> Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 06:32:28 +00:00
* desc data with appropriate padding. The 'desctype' argument is the
* assembler pseudo op defining the type of the data e.g. .asciz while
* 'descdata' is the data itself e.g. "hello, world".
*
* e.g. ELFNOTE(XYZCo, 42, .asciz, "forty-two")
* ELFNOTE(XYZCo, 12, .long, 0xdeadbeef)
*/
#define ELFNOTE_START(name, type, flags) \
.pushsection .note.name, flags,@note ; \
.balign 4 ; \
[PATCH] Translate asm version of ELFNOTE macro into preprocessor macro I've come across some problems with the assembly version of the ELFNOTE macro currently in -mm. (in x86-put-note-sections-into-a-pt_note-segment-in-vmlinux.patch) The first is that older gas does not support :varargs in .macro definitions (in my testing 2.17 does while 2.15 does not, I don't know when it became supported). The Changes file says binutils >= 2.12 so I think we need to avoid using it. There are no other uses in mainline or -mm. Old gas appears to just ignore it so you get "too many arguments" type errors. Secondly it seems that passing strings as arguments to assembler macros is broken without varargs. It looks like they get unquoted or each character is treated as a separate argument or something and this causes all manner of grief. I think this is because of the use of -traditional when compiling assembly files. Therefore I have translated the assembler macro into a pre-processor macro. I added the desctype as a separate argument instead of including it with the descdata as the previous version did since -traditional means the ELFNOTE definition after the #else needs to have the same number of arguments (I think so anyway, the -traditional CPP semantics are pretty fscking strange!). With this patch I am able to define elfnotes in assembly like this with both old and new assemblers. ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz, "linux") ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz, "2.6") ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz, "xen-3.0") ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long, __PAGE_OFFSET) Which seems reasonable enough. Signed-off-by: Ian Campbell <ian.campbell@xensource.com> Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 06:32:28 +00:00
.long 2f - 1f /* namesz */ ; \
.long 4484f - 3f /* descsz */ ; \
[PATCH] Translate asm version of ELFNOTE macro into preprocessor macro I've come across some problems with the assembly version of the ELFNOTE macro currently in -mm. (in x86-put-note-sections-into-a-pt_note-segment-in-vmlinux.patch) The first is that older gas does not support :varargs in .macro definitions (in my testing 2.17 does while 2.15 does not, I don't know when it became supported). The Changes file says binutils >= 2.12 so I think we need to avoid using it. There are no other uses in mainline or -mm. Old gas appears to just ignore it so you get "too many arguments" type errors. Secondly it seems that passing strings as arguments to assembler macros is broken without varargs. It looks like they get unquoted or each character is treated as a separate argument or something and this causes all manner of grief. I think this is because of the use of -traditional when compiling assembly files. Therefore I have translated the assembler macro into a pre-processor macro. I added the desctype as a separate argument instead of including it with the descdata as the previous version did since -traditional means the ELFNOTE definition after the #else needs to have the same number of arguments (I think so anyway, the -traditional CPP semantics are pretty fscking strange!). With this patch I am able to define elfnotes in assembly like this with both old and new assemblers. ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz, "linux") ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz, "2.6") ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz, "xen-3.0") ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long, __PAGE_OFFSET) Which seems reasonable enough. Signed-off-by: Ian Campbell <ian.campbell@xensource.com> Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 06:32:28 +00:00
.long type ; \
1:.asciz #name ; \
2:.balign 4 ; \
3:
#define ELFNOTE_END \
4484:.balign 4 ; \
[PATCH] Translate asm version of ELFNOTE macro into preprocessor macro I've come across some problems with the assembly version of the ELFNOTE macro currently in -mm. (in x86-put-note-sections-into-a-pt_note-segment-in-vmlinux.patch) The first is that older gas does not support :varargs in .macro definitions (in my testing 2.17 does while 2.15 does not, I don't know when it became supported). The Changes file says binutils >= 2.12 so I think we need to avoid using it. There are no other uses in mainline or -mm. Old gas appears to just ignore it so you get "too many arguments" type errors. Secondly it seems that passing strings as arguments to assembler macros is broken without varargs. It looks like they get unquoted or each character is treated as a separate argument or something and this causes all manner of grief. I think this is because of the use of -traditional when compiling assembly files. Therefore I have translated the assembler macro into a pre-processor macro. I added the desctype as a separate argument instead of including it with the descdata as the previous version did since -traditional means the ELFNOTE definition after the #else needs to have the same number of arguments (I think so anyway, the -traditional CPP semantics are pretty fscking strange!). With this patch I am able to define elfnotes in assembly like this with both old and new assemblers. ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz, "linux") ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz, "2.6") ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz, "xen-3.0") ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long, __PAGE_OFFSET) Which seems reasonable enough. Signed-off-by: Ian Campbell <ian.campbell@xensource.com> Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 06:32:28 +00:00
.popsection ;
#define ELFNOTE(name, type, desc) \
elfnote: mark all .note sections SHF_ALLOC ELFNOTE_START allows callers to specify flags for .pushsection assembler directives. All callsites but ELF_NOTE use "a" for SHF_ALLOC. For vdso's that explicitly use ELF_NOTE_START and BUILD_SALT, the same section is specified twice after preprocessing, once with "a" flag, once without. Example: .pushsection .note.Linux, "a", @note ; .pushsection .note.Linux, "", @note ; While GNU as allows this ordering, it warns for the opposite ordering, making these directives position dependent. We'd prefer not to precisely match this behavior in Clang's integrated assembler. Instead, the non __ASSEMBLY__ definition of ELF_NOTE uses __attribute__((section(".note.Linux"))) which is created with SHF_ALLOC, so let's make the __ASSEMBLY__ definition of ELF_NOTE consistent with C and just always use "a" flag. This allows Clang to assemble a working mainline (5.6) kernel via: $ make CC=clang AS=clang Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Fangrui Song <maskray@google.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Link: https://github.com/ClangBuiltLinux/linux/issues/913 Link: http://lkml.kernel.org/r/20200325231250.99205-1-ndesaulniers@google.com Debugged-by: Ilie Halip <ilie.halip@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 23:50:49 +00:00
ELFNOTE_START(name, type, "a") \
desc ; \
ELFNOTE_END
#else /* !__ASSEMBLER__ */
#include <uapi/linux/elf.h>
/*
* Use an anonymous structure which matches the shape of
* Elf{32,64}_Nhdr, but includes the name and desc data. The size and
* type of name and desc depend on the macro arguments. "name" must
* be a literal string, and "desc" must be passed by value. You may
* only define one note per line, since __LINE__ is used to generate
* unique symbols.
*/
#define _ELFNOTE_PASTE(a,b) a##b
#define _ELFNOTE(size, name, unique, type, desc) \
static const struct { \
struct elf##size##_note _nhdr; \
unsigned char _name[sizeof(name)] \
__attribute__((aligned(sizeof(Elf##size##_Word)))); \
typeof(desc) _desc \
__attribute__((aligned(sizeof(Elf##size##_Word)))); \
} _ELFNOTE_PASTE(_note_, unique) \
__used \
__attribute__((section(".note." name), \
aligned(sizeof(Elf##size##_Word)), \
unused)) = { \
{ \
sizeof(name), \
sizeof(desc), \
type, \
}, \
name, \
desc \
}
#define ELFNOTE(size, name, type, desc) \
_ELFNOTE(size, name, __LINE__, type, desc)
#define ELFNOTE32(name, type, desc) ELFNOTE(32, name, type, desc)
#define ELFNOTE64(name, type, desc) ELFNOTE(64, name, type, desc)
#endif /* __ASSEMBLER__ */
#endif /* _LINUX_ELFNOTE_H */