Thomas Gleixner 4f5416710e vmlinux.lds.h: Create section for protection against instrumentation ... [ Upstream commit 6553896666 ] Some code pathes, especially the low level entry code, must be protected against instrumentation for various reasons: - Low level entry code can be a fragile beast, especially on x86. - With NO_HZ_FULL RCU state needs to be established before using it. Having a dedicated section for such code allows to validate with tooling that no unsafe functions are invoked. Add the .noinstr.text section and the noinstr attribute to mark functions. noinstr implies notrace. Kprobes will gain a section check later. Provide also a set of markers: instrumentation_begin()/end() These are used to mark code inside a noinstr function which calls into regular instrumentable text section as safe. The instrumentation markers are only active when CONFIG_DEBUG_ENTRY is enabled as the end marker emits a NOP to prevent the compiler from merging the annotation points. This means the objtool verification requires a kernel compiled with this option. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134100.075416272@linutronix.de Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-02-17 10:35:16 +01:00
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.gitignore	kbuild: trivial - remove trailing empty lines	2014-06-10 00:04:06 +02:00
devicetable-offsets.c	platform-drivers-x86 for v5.1-1	2019-03-10 13:16:37 -07:00
empty.c
file2alias.c	modpost: add guid_t type definition	2019-09-04 22:55:42 +09:00
Makefile	kbuild: move modpost out of 'scripts' target	2018-12-01 23:09:34 +09:00
mk_elfconfig.c	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
modpost.c	vmlinux.lds.h: Create section for protection against instrumentation	2021-02-17 10:35:16 +01:00
modpost.h	symbol namespaces: revert to previous __ksymtab name scheme	2019-10-18 15:32:52 +02:00
sumversion.c	kbuild: remove the first line of *.mod files	2019-07-18 02:19:31 +09:00