[PATCH v4 14/16] powerpc/traps: system reset do not trace
From: Nicholas Piggin <npiggin@gmail.com>
Date: 2020-05-08 05:04:58
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
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 <redacted> Reviewed-by: Christophe Leroy <redacted> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- 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 9f6852322e59..ee209c5a1ad7 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