[v2 03/12] powerpc/mce: Add MCE notification chain

[Santosh Sivaraj]

From: Reza Arbab <arbab at linux.ibm.com>

Signed-off-by: Reza Arbab <arbab at linux.ibm.com>
---
 arch/powerpc/include/asm/asm-prototypes.h |  1 +
 arch/powerpc/include/asm/mce.h            |  4 ++++
 arch/powerpc/kernel/exceptions-64s.S      |  4 ++++
 arch/powerpc/kernel/mce.c                 | 22 ++++++++++++++++++++++
 4 files changed, 31 insertions(+)

diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index ec1c97a8e8cb..f66f26ef3ce0 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -72,6 +72,7 @@ void machine_check_exception(struct pt_regs *regs);
 void emulation_assist_interrupt(struct pt_regs *regs);
 long do_slb_fault(struct pt_regs *regs, unsigned long ea);
 void do_bad_slb_fault(struct pt_regs *regs, unsigned long ea, long err);
+void machine_check_notify(struct pt_regs *regs);
 
 /* signals, syscalls and interrupts */
 long sys_swapcontext(struct ucontext __user *old_ctx,
diff --git a/arch/powerpc/include/asm/mce.h b/arch/powerpc/include/asm/mce.h
index 94888a7025b3..948bef579086 100644
--- a/arch/powerpc/include/asm/mce.h
+++ b/arch/powerpc/include/asm/mce.h
@@ -214,4 +214,8 @@ unsigned long addr_to_pfn(struct pt_regs *regs, unsigned long addr,
 #ifdef CONFIG_PPC_BOOK3S_64
 void flush_and_reload_slb(void);
 #endif /* CONFIG_PPC_BOOK3S_64 */
+
+int mce_register_notifier(struct notifier_block *nb);
+int mce_unregister_notifier(struct notifier_block *nb);
+
 #endif /* __ASM_PPC64_MCE_H__ */
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 6b86055e5251..2e56014fca21 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -457,6 +457,10 @@ EXC_COMMON_BEGIN(machine_check_handle_early)
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	machine_check_early
 	std	r3,RESULT(r1)	/* Save result */
+
+	addi	r3,r1,STACK_FRAME_OVERHEAD
+	bl	machine_check_notify
+
 	ld	r12,_MSR(r1)
 BEGIN_FTR_SECTION
 	b	4f
diff --git a/arch/powerpc/kernel/mce.c b/arch/powerpc/kernel/mce.c
index e78c4f18ea0a..24d350a934e4 100644
--- a/arch/powerpc/kernel/mce.c
+++ b/arch/powerpc/kernel/mce.c
@@ -42,6 +42,18 @@ static struct irq_work mce_event_process_work = {
 
 DECLARE_WORK(mce_ue_event_work, machine_process_ue_event);
 
+static BLOCKING_NOTIFIER_HEAD(mce_notifier_list);
+
+int mce_register_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&mce_notifier_list, nb);
+}
+
+int mce_unregister_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&mce_notifier_list, nb);
+}
+
 static void mce_set_error_info(struct machine_check_event *mce,
 			       struct mce_error_info *mce_err)
 {
@@ -635,3 +647,13 @@ long hmi_exception_realmode(struct pt_regs *regs)
 
 	return 1;
 }
+
+void machine_check_notify(struct pt_regs *regs)
+{
+	struct machine_check_event evt;
+
+	if (!get_mce_event(&evt, MCE_EVENT_DONTRELEASE))
+		return;
+
+	blocking_notifier_call_chain(&mce_notifier_list, 0, &evt);
+}
-- 
2.20.1