Re: [PATCH v3 14/15] powerpc/64s: system reset do not trace
Le 07/04/2020 à 07:16, Nicholas Piggin a écrit : 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. Acked-by: Naveen N. Rao Signed-off-by: Nicholas Piggin Reviewed-by: Christophe Leroy --- arch/powerpc/kernel/traps.c | 5 + 1 file changed, 5 insertions(+) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 9f221772eb73..1beae89bb871 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 = this_cpu_get_ftrace_enabled(); + + this_cpu_set_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(); + this_cpu_set_ftrace_enabled(ftrace_enabled); + /* What should we do here? We could issue a shutdown or hard reset. */ }
[PATCH v3 14/15] powerpc/64s: system reset do not trace
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. Acked-by: Naveen N. Rao Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/traps.c | 5 + 1 file changed, 5 insertions(+) diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 9f221772eb73..1beae89bb871 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 = this_cpu_get_ftrace_enabled(); + + this_cpu_set_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(); + this_cpu_set_ftrace_enabled(ftrace_enabled); + /* What should we do here? We could issue a shutdown or hard reset. */ } -- 2.23.0