Nicholas Piggin wrote:
Similarly to the previous patch, do not trace system reset. This code
is used when there is a crash or hang, and tracing disturbs the system
more and has been known to crash in the crash handling path.
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/kernel/traps.c | 5 +++++
1 file changed, 5 insertions(+)
For the ftrace bits:
Acked-by: Naveen N. Rao <naveen.n....@linux.vnet.ibm.com>
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 1845fd7e161a..ed7b7a6e2dc0 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -443,6 +443,9 @@ void system_reset_exception(struct pt_regs *regs)
unsigned long hsrr0, hsrr1;
bool nested = in_nmi();
bool saved_hsrrs = false;
+ u8 ftrace_enabled = local_paca->ftrace_enabled;
+
+ local_paca->ftrace_enabled = 0;
/*
* Avoid crashes in case of nested NMI exceptions. Recoverability
@@ -524,6 +527,8 @@ void system_reset_exception(struct pt_regs *regs)
if (!nested)
nmi_exit();
+ local_paca->ftrace_enabled = ftrace_enabled;
+
I suppose we could add helpers to save/restore the state. But, since we
only have these two users as of now, we can revisit that if the need
arises.
- Naveen