[PATCH 4.14 09/62] um: Give start_idle_thread() a return code

Greg Kroah-Hartman
2018-11-26T11:00:17Z

[ Upstream commit 7ff1e34bbdc15acab823b1ee4240e94623d50ee8 ]

Fixes:
arch/um/os-Linux/skas/process.c:613:1: warning: control reaches end of
non-void function [-Wreturn-type]

longjmp() never returns but gcc still warns that the end of the function
can be reached.
Add a return code and debug aid to detect this impossible case.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/um/os-Linux/skas/process.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index c94c3bd70ccd..df4a985716eb 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -610,6 +610,11 @@ int start_idle_thread(void *stack, jmp_buf *switch_buf)
fatal_sigsegv();
}
longjmp(*switch_buf, 1);
+
+ /* unreachable */
+ printk(UM_KERN_ERR "impossible long jump!");
+ fatal_sigsegv();
+ return 0;
}

void initial_thread_cb_skas(void (*proc)(void *), void *arg)
--
2.17.1