powerpc/perf: Fix loop exit condition in nest_imc_event_init

The data structure (i.e struct imc_mem_info) to hold the memory address
information for nest imc units is allocated based on the number of nodes
in the system.

nest_imc_event_init() traverse this struct array to calculate the memory
base address for the event-cpu. If we fail to find a match for the event
cpu's chip-id in imc_mem_info struct array, then the do-while loop will
iterate until we crash.

Fix this by changing the loop exit condition based on the number of
non zero vbase elements in the array, since the allocation is done for
nr_chips + 1.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 885dcd709b ("powerpc/perf: Add nest IMC PMU support")
Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anju T Sudhakar 2018-12-18 11:50:41 +05:30 committed by Michael Ellerman
parent a913e5e8b4
commit 860b7d2286
2 changed files with 2 additions and 2 deletions

View File

@ -499,7 +499,7 @@ static int nest_imc_event_init(struct perf_event *event)
break;
}
pcni++;
} while (pcni);
} while (pcni->vbase != 0);
if (!flag)
return -ENODEV;

View File

@ -127,7 +127,7 @@ static int imc_get_mem_addr_nest(struct device_node *node,
nr_chips))
goto error;
pmu_ptr->mem_info = kcalloc(nr_chips, sizeof(*pmu_ptr->mem_info),
pmu_ptr->mem_info = kcalloc(nr_chips + 1, sizeof(*pmu_ptr->mem_info),
GFP_KERNEL);
if (!pmu_ptr->mem_info)
goto error;