cpumask: fix CONFIG_CPUMASK_OFFSTACK=y cpu hotunplug crash
Impact: Fix cpu offline when CONFIG_MAXSMP=y
Changeset bc9b83dd1f66402b870301c3c7117b9c1484abb4 "cpumask: convert
c1e_mask in arch/x86/kernel/process.c to cpumask_var_t" contained a
bug: c1e_mask is manipulated even if C1E isn't detected (and hence
not allocated).
This is simply fixed by checking for NULL (which gcc optimizes out
anyway of CONFIG_CPUMASK_OFFSTACK=n, since it knows ce1_mask can never
be NULL).
In addition, fix a leak where select_idle_routine re-allocates
(and re-clears) c1e_mask on every cpu init.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <200903171450.34549.rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index d794d94..9874dd9 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -733,6 +733,7 @@
extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
extern void select_idle_routine(const struct cpuinfo_x86 *c);
+extern void init_c1e_mask(void);
extern unsigned long boot_option_idle_override;
extern unsigned long idle_halt;