[PATCH 5.4 101/109] s390/setup: init jump labels before command line parsing

[Greg Kroah-Hartman]

From: Vasily Gorbik <gor@xxxxxxxxxxxxx>

commit 95e61b1b5d6394b53d147c0fcbe2ae70fbe09446 upstream.

Command line parameters might set static keys. This is true for s390 at
least since commit 6471384af2a6 ("mm: security: introduce init_on_alloc=1
and init_on_free=1 boot options"). To avoid the following WARN:

static_key_enable_cpuslocked(): static key 'init_on_alloc+0x0/0x40' used
before call to jump_label_init()

call jump_label_init() just before parse_early_param().
jump_label_init() is safe to call multiple times (x86 does that), doesn't
do any memory allocations and hence should be safe to call that early.

Fixes: 6471384af2a6 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Cc: <stable@xxxxxxxxxxxxxxx> # 5.3: d6df52e9996d: s390/maccess: add no DAT mode to kernel_write
Cc: <stable@xxxxxxxxxxxxxxx> # 5.3
Reviewed-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/s390/kernel/setup.c |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -1120,6 +1120,7 @@ void __init setup_arch(char **cmdline_p)
 	if (IS_ENABLED(CONFIG_EXPOLINE_AUTO))
 		nospec_auto_detect();
 
+	jump_label_init();
 	parse_early_param();
 #ifdef CONFIG_CRASH_DUMP
 	/* Deactivate elfcorehdr= kernel parameter */