cpu: Mark nmi_panic_self_stop() __noreturn

In preparation for improving objtool's handling of weak noreturn
functions, mark nmi_panic_self_stop() __noreturn.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/316fc6dfab5a8c4e024c7185484a1ee5fb0afb79.1681342859.git.jpoimboe@kernel.org

diff --git a/arch/x86/include/asm/reboot.h b/arch/x86/include/asm/reboot.h
index bc5b4d788c08dbc8f47bb8d72c7f267982e716e6..9177b4354c3f50b2c1ff7f5f454abcace0a98a60 100644 (file)
--- a/arch/x86/include/asm/reboot.h
+++ b/arch/x86/include/asm/reboot.h
@@ -28,7 +28,6 @@ void __noreturn machine_real_restart(unsigned int type);
 void cpu_emergency_disable_virtualization(void);
 
 typedef void (*nmi_shootdown_cb)(int, struct pt_regs*);
-void nmi_panic_self_stop(struct pt_regs *regs);
 void nmi_shootdown_cpus(nmi_shootdown_cb callback);
 void run_crash_ipi_callback(struct pt_regs *regs);
 

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index d03c551defccf03336a1276a97d7c79267cbb212..3adbe97015c1344ce23b896356c89fe1dd7d0de8 100644 (file)
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -920,7 +920,7 @@ void run_crash_ipi_callback(struct pt_regs *regs)
 }
 
 /* Override the weak function in kernel/panic.c */
-void nmi_panic_self_stop(struct pt_regs *regs)
+void __noreturn nmi_panic_self_stop(struct pt_regs *regs)
 {
        while (1) {
                /* If no CPU is preparing crash dump, we simply loop here. */

diff --git a/include/linux/smp.h b/include/linux/smp.h
index 2a737b39cf0aa33849bbf90deeb15d759a55e8c6..7b93504eed26cb5ef3c364ec1dac9155b57f0914 100644 (file)
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -60,7 +60,7 @@ int smp_call_function_single_async(int cpu, struct __call_single_data *csd);
  * Architecture-dependent code may override them.
  */
 void __noreturn panic_smp_self_stop(void);
-void nmi_panic_self_stop(struct pt_regs *regs);
+void __noreturn nmi_panic_self_stop(struct pt_regs *regs);
 void crash_smp_send_stop(void);
 
 /*

diff --git a/kernel/panic.c b/kernel/panic.c
index 5e4982db8dc9746685bbd0349024f39de2b72fda..886d2ebd0a0d342c24e4a6f85b92adaa0db0215e 100644 (file)
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -151,7 +151,7 @@ void __weak __noreturn panic_smp_self_stop(void)
  * Stop ourselves in NMI context if another CPU has already panicked. Arch code
  * may override this to prepare for crash dumping, e.g. save regs info.
  */
-void __weak nmi_panic_self_stop(struct pt_regs *regs)
+void __weak __noreturn nmi_panic_self_stop(struct pt_regs *regs)
 {
        panic_smp_self_stop();
 }

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 4b52ed6bff669a3ccf191f8db68d090f8afcf322..8d073bfd7d7fa406ab99f30901327d2d4fdf8f1e 100644 (file)
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -217,6 +217,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
                "lbug_with_loc",
                "machine_real_restart",
                "make_task_dead",
+               "nmi_panic_self_stop",
                "panic",
                "panic_smp_self_stop",
                "rest_init",