path: root/init
diff options
authorArd Biesheuvel <>2017-02-03 09:54:05 +0000
committerLinus Torvalds <>2017-02-03 08:28:25 -0800
commit56067812d5b0e737ac2063e94a50f76b810d6ca3 (patch)
tree1627e6abc9001f0b519ed65daa86be46d52c4117 /init
parent34e00accf612bc5448ae709245c2b408edf39f46 (diff)
kbuild: modversions: add infrastructure for emitting relative CRCs
This add the kbuild infrastructure that will allow architectures to emit vmlinux symbol CRCs as 32-bit offsets to another location in the kernel where the actual value is stored. This works around problems with CRCs being mistaken for relocatable symbols on kernels that self relocate at runtime (i.e., powerpc with CONFIG_RELOCATABLE=y) For the kbuild side of things, this comes down to the following: - introducing a Kconfig symbol MODULE_REL_CRCS - adding a -R switch to genksyms to instruct it to emit the CRC symbols as references into the .rodata section - making modpost distinguish such references from absolute CRC symbols by the section index (SHN_ABS) - making kallsyms disregard non-absolute symbols with a __crc_ prefix Signed-off-by: Ard Biesheuvel <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'init')
1 files changed, 4 insertions, 0 deletions
diff --git a/init/Kconfig b/init/Kconfig
index e1a93734..4dd8bd2 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1987,6 +1987,10 @@ config MODVERSIONS
make them incompatible with the kernel you are running. If
unsure, say N.
+ bool
+ depends on MODVERSIONS
bool "Source checksum for all modules"