Linux Kernel https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.7.9 2024-02-23T08:51:39Z 2024-02-23T08:51:39Z Nathan Chancellor nathan@kernel.org 2024-01-23T22:59:55Z urn:sha1:3f9ba399b0e9ae572fcf4ec104aca85adda27a7a commit 397586506c3da005b9333ce5947ad01e8018a3be upstream. After the linked LLVM change, building ARCH=um defconfig results in a segmentation fault in modpost. Prior to commit a23e7584ecf3 ("modpost: unify 'sym' and 'to' in default_mismatch_handler()"), there was a warning: WARNING: modpost: vmlinux.o(__ex_table+0x88): Section mismatch in reference to the .ltext:(unknown) WARNING: modpost: The relocation at __ex_table+0x88 references section ".ltext" which is not in the list of authorized sections. If you're adding a new section and/or if this reference is valid, add ".ltext" to the list of authorized sections to jump to on fault. This can be achieved by adding ".ltext" to OTHER_TEXT_SECTIONS in scripts/mod/modpost.c. The linked LLVM change moves global objects to the '.ltext' (and '.ltext.*' with '-ffunction-sections') sections with '-mcmodel=large', which ARCH=um uses. These sections should be handled just as '.text' and '.text.*' are, so add them to TEXT_SECTIONS. Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/1981 Link: https://github.com/llvm/llvm-project/commit/4bf8a688956a759b7b6b8d94f42d25c13c7af130 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 2023-11-16T11:14:44Z Masahiro Yamada masahiroy@kernel.org 2023-10-31T17:46:27Z urn:sha1:1c4a7587d1bbee0fd53b63af60e4244a62775f57 The section mismatch check prints a bogus symbol name on some architectures. [test code] #include <linux/init.h> int __initdata foo; int get_foo(void) { return foo; } If you compile it with GCC for riscv or loongarch, modpost will show an incorrect symbol name: WARNING: modpost: vmlinux: section mismatch in reference: get_foo+0x8 (section: .text) -> done (section: .init.data) To get the correct symbol address, the st_value must be added. This issue has never been noticed since commit 93684d3b8062 ("kbuild: include symbol names in section mismatch warnings") presumably because st_value becomes zero on most architectures when the referenced symbol is looked up. It is not true for riscv or loongarch, at least. With this fix, modpost will show the correct symbol name: WARNING: modpost: vmlinux: section mismatch in reference: get_foo+0x8 (section: .text) -> foo (section: .init.data) Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:13Z urn:sha1:34fcf231dcf94d7dea29c070228c4b93849f4850 ALL_INIT_TEXT_SECTIONS and ALL_EXIT_TEXT_SECTIONS are only used in the macro definition of ALL_TEXT_SECTIONS. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:12Z urn:sha1:b3d4f446fc0f6bf6d50abfc403eb375d9b9f6378 Check symbol references from normal sections to init/exit sections in a single entry. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:11Z urn:sha1:e578e4e3110635b20786e442baa3aeff9bb65f95 ALL_INIT_SECTIONS is defined as follows: #define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:10Z urn:sha1:a3df1526da480c089c20868b7f4d486b9f266001 Theoretically, we could export conditionally-discarded code sections, such as .meminit*, if all the users can become modular under a certain condition. However, that would be difficult to control and such a tricky case has never occurred. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:09Z urn:sha1:48cd8df7afd1eef22cf7b125697a6d7c3d168c5c ALL_EXIT_SECTIONS and EXIT_SECTIONS are the same. Remove the latter. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:08Z urn:sha1:473a45bb35f080e31cb4fe45e905bfe3bd407fdf ALL_XXXINIT_SECTIONS and MEM_INIT_SECTIONS are the same. Remove the latter. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:07Z urn:sha1:e1dc1bfe5b27842c9e43a1f2d42c34decb0660c3 These symbol patterns were whitelisted to allow them to reference to functions with the old __devinit and __devexit annotations. We stopped doing this a long time ago, for example, commit 6f039790510f ("Drivers: scsi: remove __dev* attributes.") remove those annotations from the scsi drivers. Keep *_ops, *_probe, and *_console, otherwise they will really cause section mismatch warnings. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> 2023-10-28T12:31:22Z Masahiro Yamada masahiroy@kernel.org 2023-10-22T17:06:06Z urn:sha1:50cccec15c48814765895891ca0d95d989b6a419 Drivers must not reference .meminit* sections, which are discarded when CONFIG_MEMORY_HOTPLUG=n. The reason for whitelisting "*driver" in the section mismatch check was to allow drivers to reference symbols annotated as __devinit or __devexit that existed in the past. Those annotations were removed by the following commits: - 54b956b90360 ("Remove __dev* markings from init.h") - 92e9e6d1f984 ("modpost.c: Stop checking __dev* section mismatches") Remove the stale whitelist. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>