[PATCH AUTOSEL 5.3 49/87] powerpc/perf: fix imc allocation failure handling

From: Sasha Levin
Date: Tue Sep 24 2019 - 12:44:04 EST


From: Nicholas Piggin <npiggin@xxxxxxxxx>

[ Upstream commit 10c4bd7cd28e77aeb8cfa65b23cb3c632ede2a49 ]

The alloc_pages_node return value should be tested for failure
before being passed to page_address.

Tested-by: Anju T Sudhakar <anju@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20190724084638.24982-3-npiggin@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/perf/imc-pmu.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c
index dea243185ea4b..cb50a9e1fd2d7 100644
--- a/arch/powerpc/perf/imc-pmu.c
+++ b/arch/powerpc/perf/imc-pmu.c
@@ -577,6 +577,7 @@ static int core_imc_mem_init(int cpu, int size)
{
int nid, rc = 0, core_id = (cpu / threads_per_core);
struct imc_mem_info *mem_info;
+ struct page *page;

/*
* alloc_pages_node() will allocate memory for core in the
@@ -587,11 +588,12 @@ static int core_imc_mem_init(int cpu, int size)
mem_info->id = core_id;

/* We need only vbase for core counters */
- mem_info->vbase = page_address(alloc_pages_node(nid,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
- __GFP_NOWARN, get_order(size)));
- if (!mem_info->vbase)
+ page = alloc_pages_node(nid,
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size));
+ if (!page)
return -ENOMEM;
+ mem_info->vbase = page_address(page);

/* Init the mutex */
core_imc_refc[core_id].id = core_id;
@@ -849,15 +851,17 @@ static int thread_imc_mem_alloc(int cpu_id, int size)
int nid = cpu_to_node(cpu_id);

if (!local_mem) {
+ struct page *page;
/*
* This case could happen only once at start, since we dont
* free the memory in cpu offline path.
*/
- local_mem = page_address(alloc_pages_node(nid,
+ page = alloc_pages_node(nid,
GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
- __GFP_NOWARN, get_order(size)));
- if (!local_mem)
+ __GFP_NOWARN, get_order(size));
+ if (!page)
return -ENOMEM;
+ local_mem = page_address(page);

per_cpu(thread_imc_mem, cpu_id) = local_mem;
}
@@ -1095,11 +1099,14 @@ static int trace_imc_mem_alloc(int cpu_id, int size)
int core_id = (cpu_id / threads_per_core);

if (!local_mem) {
- local_mem = page_address(alloc_pages_node(phys_id,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
- __GFP_NOWARN, get_order(size)));
- if (!local_mem)
+ struct page *page;
+
+ page = alloc_pages_node(phys_id,
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size));
+ if (!page)
return -ENOMEM;
+ local_mem = page_address(page);
per_cpu(trace_imc_mem, cpu_id) = local_mem;

/* Initialise the counters for trace mode */
--
2.20.1