[PATCH AUTOSEL 5.0 029/317] powerpc/perf: Return accordingly on invalid chip-id in

Sasha Levin
2019-05-22T19:24:28Z

From: Anju T Sudhakar <anju@linux.vnet.ibm.com>

[ Upstream commit a913e5e8b43be1d3897a141ce61c1ec071cad89c ]

Nest hardware counter memory resides in a per-chip reserve-memory.
During nest_imc_event_init(), chip-id of the event-cpu is considered to
calculate the base memory addresss for that cpu. Return, proper error
condition if the chip_id calculated is invalid.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 885dcd709ba91 ("powerpc/perf: Add nest IMC PMU support")
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/perf/imc-pmu.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index f292a3f284f1c..4f34c7557bdb7 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -496,6 +496,11 @@ static int nest_imc_event_init(struct perf_event *event)
* Get the base memory addresss for this cpu.
*/
chip_id = cpu_to_chip_id(event->cpu);
+
+ /* Return, if chip_id is not valid */
+ if (chip_id < 0)
+ return -ENODEV;
+
pcni = pmu->mem_info;
do {
if (pcni->id == chip_id) {
--
2.20.1