kexec: migrate to reboot cpu
Commit 1b3a5d02ee07 ("reboot: move arch/x86 reboot= handling to generic
kernel") moved reboot= handling to generic code. In the process it also
removed the code in native_machine_shutdown() which are moving reboot
process to reboot_cpu/cpu0.
I guess that thought must have been that all reboot paths are calling
migrate_to_reboot_cpu(), so we don't need this special handling. But
kexec reboot path (kernel_kexec()) is not calling
migrate_to_reboot_cpu() so above change broke kexec. Now reboot can
happen on non-boot cpu and when INIT is sent in second kerneo to bring
up BP, it brings down the machine.
So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
this problem.
Bisected by WANG Chao.
Reported-by: Matthew Whitehead <[email protected]>
Reported-by: Dave Young <[email protected]>
Signed-off-by: Vivek Goyal <[email protected]>
Tested-by: Baoquan He <[email protected]>
Tested-by: WANG Chao <[email protected]>
Acked-by: H. Peter Anvin <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index 8e00f9f..9e7db9e 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -43,6 +43,7 @@
* Architecture-specific implementations of sys_reboot commands.
*/
+extern void migrate_to_reboot_cpu(void);
extern void machine_restart(char *cmd);
extern void machine_halt(void);
extern void machine_power_off(void);
