init: allow initcall tables to be emitted using relative references

Allow the initcall tables to be emitted using relative references that
are only half the size on 64-bit architectures and don't require fixups
at runtime on relocatable kernels.

Link: http://lkml.kernel.org/r/20180704083651.24360-5-ard.biesheuvel@linaro.org
Acked-by: James Morris <james.morris@microsoft.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ard Biesheuvel 2018-08-21 21:56:13 -07:00 committed by Linus Torvalds
parent 7290d58095
commit 1b1eeca7e4
4 changed files with 67 additions and 40 deletions

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@ -116,8 +116,24 @@
typedef int (*initcall_t)(void); typedef int (*initcall_t)(void);
typedef void (*exitcall_t)(void); typedef void (*exitcall_t)(void);
extern initcall_t __con_initcall_start[], __con_initcall_end[]; #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
extern initcall_t __security_initcall_start[], __security_initcall_end[]; typedef int initcall_entry_t;
static inline initcall_t initcall_from_entry(initcall_entry_t *entry)
{
return offset_to_ptr(entry);
}
#else
typedef initcall_t initcall_entry_t;
static inline initcall_t initcall_from_entry(initcall_entry_t *entry)
{
return *entry;
}
#endif
extern initcall_entry_t __con_initcall_start[], __con_initcall_end[];
extern initcall_entry_t __security_initcall_start[], __security_initcall_end[];
/* Used for contructor calls. */ /* Used for contructor calls. */
typedef void (*ctor_fn_t)(void); typedef void (*ctor_fn_t)(void);
@ -167,9 +183,20 @@ extern bool initcall_debug;
* as KEEP() in the linker script. * as KEEP() in the linker script.
*/ */
#define __define_initcall(fn, id) \ #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
#define ___define_initcall(fn, id, __sec) \
__ADDRESSABLE(fn) \
asm(".section \"" #__sec ".init\", \"a\" \n" \
"__initcall_" #fn #id ": \n" \
".long " #fn " - . \n" \
".previous \n");
#else
#define ___define_initcall(fn, id, __sec) \
static initcall_t __initcall_##fn##id __used \ static initcall_t __initcall_##fn##id __used \
__attribute__((__section__(".initcall" #id ".init"))) = fn; __attribute__((__section__(#__sec ".init"))) = fn;
#endif
#define __define_initcall(fn, id) ___define_initcall(fn, id, .initcall##id)
/* /*
* Early initcalls run before initializing SMP. * Early initcalls run before initializing SMP.
@ -208,13 +235,8 @@ extern bool initcall_debug;
#define __exitcall(fn) \ #define __exitcall(fn) \
static exitcall_t __exitcall_##fn __exit_call = fn static exitcall_t __exitcall_##fn __exit_call = fn
#define console_initcall(fn) \ #define console_initcall(fn) ___define_initcall(fn,, .con_initcall)
static initcall_t __initcall_##fn \ #define security_initcall(fn) ___define_initcall(fn,, .security_initcall)
__used __section(.con_initcall.init) = fn
#define security_initcall(fn) \
static initcall_t __initcall_##fn \
__used __section(.security_initcall.init) = fn
struct obs_kernel_param { struct obs_kernel_param {
const char *str; const char *str;

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@ -902,18 +902,18 @@ int __init_or_module do_one_initcall(initcall_t fn)
} }
extern initcall_t __initcall_start[]; extern initcall_entry_t __initcall_start[];
extern initcall_t __initcall0_start[]; extern initcall_entry_t __initcall0_start[];
extern initcall_t __initcall1_start[]; extern initcall_entry_t __initcall1_start[];
extern initcall_t __initcall2_start[]; extern initcall_entry_t __initcall2_start[];
extern initcall_t __initcall3_start[]; extern initcall_entry_t __initcall3_start[];
extern initcall_t __initcall4_start[]; extern initcall_entry_t __initcall4_start[];
extern initcall_t __initcall5_start[]; extern initcall_entry_t __initcall5_start[];
extern initcall_t __initcall6_start[]; extern initcall_entry_t __initcall6_start[];
extern initcall_t __initcall7_start[]; extern initcall_entry_t __initcall7_start[];
extern initcall_t __initcall_end[]; extern initcall_entry_t __initcall_end[];
static initcall_t *initcall_levels[] __initdata = { static initcall_entry_t *initcall_levels[] __initdata = {
__initcall0_start, __initcall0_start,
__initcall1_start, __initcall1_start,
__initcall2_start, __initcall2_start,
@ -939,7 +939,7 @@ static char *initcall_level_names[] __initdata = {
static void __init do_initcall_level(int level) static void __init do_initcall_level(int level)
{ {
initcall_t *fn; initcall_entry_t *fn;
strcpy(initcall_command_line, saved_command_line); strcpy(initcall_command_line, saved_command_line);
parse_args(initcall_level_names[level], parse_args(initcall_level_names[level],
@ -950,7 +950,7 @@ static void __init do_initcall_level(int level)
trace_initcall_level(initcall_level_names[level]); trace_initcall_level(initcall_level_names[level]);
for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++) for (fn = initcall_levels[level]; fn < initcall_levels[level+1]; fn++)
do_one_initcall(*fn); do_one_initcall(initcall_from_entry(fn));
} }
static void __init do_initcalls(void) static void __init do_initcalls(void)
@ -981,11 +981,11 @@ static void __init do_basic_setup(void)
static void __init do_pre_smp_initcalls(void) static void __init do_pre_smp_initcalls(void)
{ {
initcall_t *fn; initcall_entry_t *fn;
trace_initcall_level("early"); trace_initcall_level("early");
for (fn = __initcall_start; fn < __initcall0_start; fn++) for (fn = __initcall_start; fn < __initcall0_start; fn++)
do_one_initcall(*fn); do_one_initcall(initcall_from_entry(fn));
} }
/* /*

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@ -2788,7 +2788,8 @@ EXPORT_SYMBOL(unregister_console);
void __init console_init(void) void __init console_init(void)
{ {
int ret; int ret;
initcall_t *call; initcall_t call;
initcall_entry_t *ce;
/* Setup the default TTY line discipline. */ /* Setup the default TTY line discipline. */
n_tty_init(); n_tty_init();
@ -2797,13 +2798,14 @@ void __init console_init(void)
* set up the console device so that later boot sequences can * set up the console device so that later boot sequences can
* inform about problems etc.. * inform about problems etc..
*/ */
call = __con_initcall_start; ce = __con_initcall_start;
trace_initcall_level("console"); trace_initcall_level("console");
while (call < __con_initcall_end) { while (ce < __con_initcall_end) {
trace_initcall_start((*call)); call = initcall_from_entry(ce);
ret = (*call)(); trace_initcall_start(call);
trace_initcall_finish((*call), ret); ret = call();
call++; trace_initcall_finish(call, ret);
ce++;
} }
} }

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@ -48,14 +48,17 @@ static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
static void __init do_security_initcalls(void) static void __init do_security_initcalls(void)
{ {
int ret; int ret;
initcall_t *call; initcall_t call;
call = __security_initcall_start; initcall_entry_t *ce;
ce = __security_initcall_start;
trace_initcall_level("security"); trace_initcall_level("security");
while (call < __security_initcall_end) { while (ce < __security_initcall_end) {
trace_initcall_start((*call)); call = initcall_from_entry(ce);
ret = (*call) (); trace_initcall_start(call);
trace_initcall_finish((*call), ret); ret = call();
call++; trace_initcall_finish(call, ret);
ce++;
} }
} }