user/sven/linux.git/scripts/basic, branch v5.8.17

modpost,fixdep: Replace zero-length array with flexible-array

2020-05-25T15:03:16Z

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: Masahiro Yamada

Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

2020-04-03T20:12:26Z

Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48Z

Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada Signed-off-by: Greg Kroah-Hartman

fixdep: remove redundant null character check

2020-03-02T12:18:19Z

If *q is '\0', the condition (isalnum(*q) || *q == '_') is false anyway. It is redundant to ensure non-zero *q. Signed-off-by: Masahiro Yamada

fixdep: remove unneeded code and comments about *.ver files

2020-03-02T12:18:19Z

This is probably stale code. In old days (~ Linux 2.5.59), Kbuild made genksyms generate include/linux/modules/*.ver files. The currenct Kbuild does not generate *.ver files at all. Signed-off-by: Masahiro Yamada

kbuild: rename hostprogs-y/always to hostprogs/always-y

2020-02-03T16:53:07Z

In old days, the "host-progs" syntax was used for specifying host programs. It was renamed to the current "hostprogs-y" in 2004. It is typically useful in scripts/Makefile because it allows Kbuild to selectively compile host programs based on the kernel configuration. This commit renames like follows: always -> always-y hostprogs-y -> hostprogs So, scripts/Makefile will look like this: always-$(CONFIG_BUILD_BIN2C) += ... always-$(CONFIG_KALLSYMS) += ... ... hostprogs := $(always-y) $(always-m) I think this makes more sense because a host program is always a host program, irrespective of the kernel configuration. We want to specify which ones to compile by CONFIG options, so always-y will be handier. The "always", "hostprogs-y", "hostprogs-m" will be kept for backward compatibility for a while. Signed-off-by: Masahiro Yamada

kbuild: remove unneeded comments and code from scripts/basic/Makefile

2019-08-29T14:54:29Z

Kbuild descends into scripts/basic/ even before the Kconfig. I do not expect any other host programs added to this Makefile. Signed-off-by: Masahiro Yamada

fixdep: check return value of printf() and putchar()

2019-07-01T01:30:39Z

When there is not enough space on your storage device, the build will fail with 'No space left on device' error message. The reason is obvious from the message, so you will free up some disk space, then you will resume the build. However, sometimes you may still see a mysterious error message: unterminated call to function 'wildcard': missing ')'. If you run out of the disk space, fixdep may end up with generating incomplete .*.cmd files. For example, if the disk-full error occurs while fixdep is running print_dep(), the .*.cmd might be truncated like this: $(wildcard include/config/ When you run 'make' next time, this broken .*.cmd will be included, then Make will terminate parsing since it is a wrong syntax. Once this happens, you need to run 'make clean' or delete the broken .*.cmd file manually. Even if you do not see any error message, the .*.cmd files after any error could be potentially incomplete, and unreliable. You may miss the re-compilation due to missing header dependency. If printf() cannot output the string for disk shortage or whatever reason, it returns a negative value, but currently fixdep does not check it at all. Consequently, fixdep *successfully* generates a broken .*.cmd file. Make never notices that since fixdep exits with 0, which means success. Given the intended usage of fixdep, it must respect the return value of not only malloc(), but also printf() and putchar(). This seems a long-standing issue since the introduction of fixdep. In old days, Kbuild tried to provide an extra safety by letting fixdep output to a temporary file and renaming it after everything is done: scripts/basic/fixdep $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;\ rm -f $(depfile); \ mv -f $(dot-target).tmp $(dot-target).cmd) It was no help to avoid the current issue; fixdep successfully created a truncated tmp file, which would be renamed to a .*.cmd file. This problem should be fixed by propagating the error status to the build system because: [1] Since commit 9c2af1c7377a ("kbuild: add .DELETE_ON_ERROR special target"), Make will delete the target automatically on any failure in the recipe. [2] Since commit 392885ee82d3 ("kbuild: let fixdep directly write to .*.cmd files"), .*.cmd file is included only when the corresponding target already exists. Signed-off-by: Masahiro Yamada

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46Z

Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS

2018-12-01T14:13:14Z

My main motivation of this commit is to clean up scripts/Kbuild.include and scripts/Makefile.build. Currently, CONFIG_TRIM_UNUSED_KSYMS works with a tricky gimmick; possibly exported symbols are detected by letting $(CPP) replace EXPORT_SYMBOL* with a special string '=== __KSYM_*===', which is post-processed by sed, and passed to fixdep. The extra preprocessing is costly, and hacking cmd_and_fixdep is ugly. I came up with a new way to find exported symbols; insert a dummy symbol __ksym_marker_* to each potentially exported symbol. Those dummy symbols are picked up by $(NM), post-processed by sed, then appended to .*.cmd files. I collected the post-process part to a new shell script scripts/gen_ksymdeps.sh for readability. The dummy symbols are put into the .discard.* section so that the linker script rips them off the final vmlinux or modules. A nice side-effect is building with CONFIG_TRIM_UNUSED_KSYMS will be much faster. Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Pitre