diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-08-31 10:42:24 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-10-09 11:20:55 +0200 |
| commit | 53c99bd665a2649341ed6aed358ab56a3eedcd00 (patch) | |
| tree | b7fb2be29c66039b6f986f988e064bfdff7dd392 | |
| parent | 00e9e6645adc2c02c9ec5b42fd39d2a7f0880e6a (diff) | |
| download | lwn-53c99bd665a2649341ed6aed358ab56a3eedcd00.tar.gz lwn-53c99bd665a2649341ed6aed358ab56a3eedcd00.zip | |
init: add arch_call_rest_init to allow stack switching
With CONFIG_VMAP_STACK=y the kernel stack of all tasks should be
allocated in the vmalloc space. The initial stack used for all
the early init code is in the init_thread_union. To be able to
switch from this early stack to a properly allocated stack
from vmalloc the architecture needs a switch-over point.
Introduce the arch_call_rest_init() function with a weak definition
in init/main.c with the only purpose to call rest_init() from the
end of start_kernel(). The architecture override can then do the
necessary magic to switch to the new vmalloc'ed stack.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| -rw-r--r-- | include/linux/start_kernel.h | 2 | ||||
| -rw-r--r-- | init/main.c | 9 |
2 files changed, 9 insertions, 2 deletions
diff --git a/include/linux/start_kernel.h b/include/linux/start_kernel.h index 4b268d86a784..8b369a41c03c 100644 --- a/include/linux/start_kernel.h +++ b/include/linux/start_kernel.h @@ -9,5 +9,7 @@ up something else. */ extern asmlinkage void __init start_kernel(void); +extern void __init arch_call_rest_init(void); +extern void __ref rest_init(void); #endif /* _LINUX_START_KERNEL_H */ diff --git a/init/main.c b/init/main.c index 18f8f0140fa0..78b714a5fa94 100644 --- a/init/main.c +++ b/init/main.c @@ -394,7 +394,7 @@ static void __init setup_command_line(char *command_line) static __initdata DECLARE_COMPLETION(kthreadd_done); -static noinline void __ref rest_init(void) +noinline void __ref rest_init(void) { struct task_struct *tsk; int pid; @@ -528,6 +528,11 @@ static void __init mm_init(void) pti_init(); } +void __init __weak arch_call_rest_init(void) +{ + rest_init(); +} + asmlinkage __visible void __init start_kernel(void) { char *command_line; @@ -736,7 +741,7 @@ asmlinkage __visible void __init start_kernel(void) } /* Do the rest non-__init'ed, we're now alive */ - rest_init(); + arch_call_rest_init(); } /* Call all constructor functions linked into the kernel. */ |