4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cai Li <cai.li@xxxxxxxxxxxxxx> [ Upstream commit 975b820b6836b6b6c42fb84cd2e772e2b41bca67 ] In some cases the clock parent would be set NULL when doing re-parent, it will cause a NULL pointer accessing if clk_set trace event is enabled. This patch sets the parent as "none" if the input parameter is NULL. Fixes: dfc202ead312 (clk: Add tracepoints for hardware operations) Signed-off-by: Cai Li <cai.li@xxxxxxxxxxxxxx> Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxxxxxx> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/trace/events/clk.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/trace/events/clk.h +++ b/include/trace/events/clk.h @@ -134,12 +134,12 @@ DECLARE_EVENT_CLASS(clk_parent, TP_STRUCT__entry( __string( name, core->name ) - __string( pname, parent->name ) + __string( pname, parent ? parent->name : "none" ) ), TP_fast_assign( __assign_str(name, core->name); - __assign_str(pname, parent->name); + __assign_str(pname, parent ? parent->name : "none"); ), TP_printk("%s %s", __get_str(name), __get_str(pname))