diff options
Diffstat (limited to 'include/linux/init.h')
| -rw-r--r-- | include/linux/init.h | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/include/linux/init.h b/include/linux/init.h index e1688802964..2df8e8dd10a 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -163,6 +163,23 @@ extern bool initcall_debug; #ifndef __ASSEMBLY__ +#ifdef CONFIG_LTO +/* Work around a LTO gcc problem: when there is no reference to a variable + * in a module it will be moved to the end of the program. This causes + * reordering of initcalls which the kernel does not like. + * Add a dummy reference function to avoid this. The function is + * deleted by the linker. + */ +#define LTO_REFERENCE_INITCALL(x) \ + ; /* yes this is needed */ \ + static __used __exit void *reference_##x(void) \ + { \ + return &x; \ + } +#else +#define LTO_REFERENCE_INITCALL(x) +#endif + /* initcalls are now grouped by functionality into separate * subsections. Ordering inside the subsections is determined * by link order. @@ -175,7 +192,8 @@ extern bool initcall_debug; #define __define_initcall(fn, id) \ static initcall_t __initcall_##fn##id __used \ - __attribute__((__section__(".initcall" #id ".init"))) = fn + __attribute__((__section__(".initcall" #id ".init"))) = fn; \ + LTO_REFERENCE_INITCALL(__initcall_##fn##id) /* * Early initcalls run before initializing SMP. @@ -279,16 +297,28 @@ void __init parse_early_options(char *cmdline); #else /* MODULE */ -/* Don't use these in loadable modules, but some people do... */ +/* + * In most cases loadable modules do not need custom + * initcall levels. There are still some valid cases where + * a driver may be needed early if built in, and does not + * matter when built as a loadable module. Like bus + * snooping debug drivers. + */ #define early_initcall(fn) module_init(fn) #define core_initcall(fn) module_init(fn) +#define core_initcall_sync(fn) module_init(fn) #define postcore_initcall(fn) module_init(fn) +#define postcore_initcall_sync(fn) module_init(fn) #define arch_initcall(fn) module_init(fn) #define subsys_initcall(fn) module_init(fn) +#define subsys_initcall_sync(fn) module_init(fn) #define fs_initcall(fn) module_init(fn) +#define fs_initcall_sync(fn) module_init(fn) #define rootfs_initcall(fn) module_init(fn) #define device_initcall(fn) module_init(fn) +#define device_initcall_sync(fn) module_init(fn) #define late_initcall(fn) module_init(fn) +#define late_initcall_sync(fn) module_init(fn) #define console_initcall(fn) module_init(fn) #define security_initcall(fn) module_init(fn) |