From: Tuan Phan tuanphan@os.amperecomputing.com
[ Upstream commit 4e16f283edc289820e9b2d6f617ed8e514ee8396 ]
When multiple dtcs share the same IRQ number, the irq_friend which used to refer to dtc object gets calculated incorrect which leads to invalid pointer.
Fixes: 0ba64770a2f2 ("perf: Add Arm CMN-600 PMU driver")
Signed-off-by: Tuan Phan tuanphan@os.amperecomputing.com Reviewed-by: Robin Murphy robin.murphy@arm.com Link: https://lore.kernel.org/r/1623946129-3290-1-git-send-email-tuanphan@os.amper... Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/perf/arm-cmn.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index 46defb1dcf86..bb019e383988 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -1212,7 +1212,7 @@ static int arm_cmn_init_irqs(struct arm_cmn *cmn) irq = cmn->dtc[i].irq; for (j = i; j--; ) { if (cmn->dtc[j].irq == irq) { - cmn->dtc[j].irq_friend = j - i; + cmn->dtc[j].irq_friend = i - j; goto next; } }