4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jason Baron <jba...@akamai.com> [ Upstream commit 92ee46efeb505ead3ab06d3c5ce695637ed5f152 ] Fengguang Wu reported that running the rcuperf test during boot can cause the jump_label_test() to hit a WARN_ON(). The issue is that the core jump label code relies on kernel_text_address() to detect when it can no longer update branches that may be contained in __init sections. The kernel_text_address() in turn assumes that if the system_state variable is greter than or equal to SYSTEM_RUNNING then __init sections are no longer valid (since the assumption is that they have been freed). However, when rcuperf is setup to run in early boot it can call kernel_power_off() which sets the system_state to SYSTEM_POWER_OFF. Since rcuperf initialization is invoked via a module_init(), we can make the dependency of jump_label_test() needing to complete before rcuperf explicit by calling it via early_initcall(). Reported-by: Fengguang Wu <fengguang...@intel.com> Signed-off-by: Jason Baron <jba...@akamai.com> Acked-by: Paul E. McKenney <paul...@linux.vnet.ibm.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Steven Rostedt <rost...@goodmis.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/1510609727-2238-1-git-send-email-jba...@akamai.com Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Sasha Levin <alexander.le...@verizon.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- kernel/jump_label.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -553,7 +553,7 @@ static __init int jump_label_test(void) return 0; } -late_initcall(jump_label_test); +early_initcall(jump_label_test); #endif /* STATIC_KEYS_SELFTEST */ #endif /* HAVE_JUMP_LABEL */
