Re: [PATCH 1/4] powerpc/perf: Rearrange memory freeing in imc init
From: Madhavan Srinivasan <hidden>
Date: 2018-05-03 03:33:50
On Monday 09 April 2018 02:30 PM, Anju T Sudhakar wrote:
When any of the IMC (In-Memory Collection counter) devices fail to initialize, imc_common_mem_free() frees set of memory. In doing so, pmu_ptr pointer is also freed. But pmu_ptr pointer is used in subsequent function (imc_common_cpuhp_mem_free()) which is wrong. Patch here reorders the code to avoid such access. Also free the memory which is dynamically allocated during imc initialization, wherever required.
Reviewed-by: Madhavan Srinivasan <redacted>
quoted hunk ↗ jump to hunk
Signed-off-by: Anju T Sudhakar <redacted> --- test matrix and static checker run details are updated in the cover letter patch is based on https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git (branch: merge) arch/powerpc/perf/imc-pmu.c | 32 ++++++++++++++++--------------- arch/powerpc/platforms/powernv/opal-imc.c | 13 ++++++++++--- 2 files changed, 27 insertions(+), 18 deletions(-)diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c index d7532e7..258b0f4 100644 --- a/arch/powerpc/perf/imc-pmu.c +++ b/arch/powerpc/perf/imc-pmu.c@@ -1153,7 +1153,7 @@ static void cleanup_all_core_imc_memory(void) /* mem_info will never be NULL */ for (i = 0; i < nr_cores; i++) { if (ptr[i].vbase) - free_pages((u64)ptr->vbase, get_order(size)); + free_pages((u64)ptr[i].vbase, get_order(size)); } kfree(ptr);@@ -1191,7 +1191,6 @@ static void imc_common_mem_free(struct imc_pmu *pmu_ptr) if (pmu_ptr->attr_groups[IMC_EVENT_ATTR]) kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs); kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]); - kfree(pmu_ptr); } /*@@ -1208,6 +1207,7 @@ static void imc_common_cpuhp_mem_free(struct imc_pmu *pmu_ptr) cpuhp_remove_state(CPUHP_AP_PERF_POWERPC_NEST_IMC_ONLINE); kfree(nest_imc_refc); kfree(per_nest_pmu_arr); + per_nest_pmu_arr = NULL; } if (nest_pmus > 0)@@ -1319,10 +1319,8 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id int ret; ret = imc_mem_init(pmu_ptr, parent, pmu_idx); - if (ret) { - imc_common_mem_free(pmu_ptr); - return ret; - } + if (ret) + goto err_free_mem; switch (pmu_ptr->domain) { case IMC_DOMAIN_NEST:@@ -1337,7 +1335,9 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id ret = init_nest_pmu_ref(); if (ret) { mutex_unlock(&nest_init_lock); - goto err_free; + kfree(per_nest_pmu_arr); + per_nest_pmu_arr = NULL; + goto err_free_mem; } /* Register for cpu hotplug notification. */ ret = nest_pmu_cpumask_init();@@ -1345,7 +1345,8 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id mutex_unlock(&nest_init_lock); kfree(nest_imc_refc); kfree(per_nest_pmu_arr); - goto err_free; + per_nest_pmu_arr = NULL; + goto err_free_mem; } } nest_pmus++;@@ -1355,7 +1356,7 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id ret = core_imc_pmu_cpumask_init(); if (ret) { cleanup_all_core_imc_memory(); - return ret; + goto err_free_mem; } break;@@ -1363,7 +1364,7 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id ret = thread_imc_cpu_init(); if (ret) { cleanup_all_thread_imc_memory(); - return ret; + goto err_free_mem; } break;@@ -1373,23 +1374,24 @@ int init_imc_pmu(struct device_node *parent, struct imc_pmu *pmu_ptr, int pmu_id ret = update_events_in_group(parent, pmu_ptr); if (ret) - goto err_free; + goto err_free_cpuhp_mem; ret = update_pmu_ops(pmu_ptr); if (ret) - goto err_free; + goto err_free_cpuhp_mem; ret = perf_pmu_register(&pmu_ptr->pmu, pmu_ptr->pmu.name, -1); if (ret) - goto err_free; + goto err_free_cpuhp_mem; pr_info("%s performance monitor hardware support registered\n", pmu_ptr->pmu.name); return 0; -err_free: - imc_common_mem_free(pmu_ptr); +err_free_cpuhp_mem: imc_common_cpuhp_mem_free(pmu_ptr); +err_free_mem: + imc_common_mem_free(pmu_ptr); return ret; }diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index 2a14fda..490bb72 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c@@ -115,8 +115,10 @@ static int imc_get_mem_addr_nest(struct device_node *node, return -ENOMEM; chipid_arr = kcalloc(nr_chips, sizeof(*chipid_arr), GFP_KERNEL); - if (!chipid_arr) + if (!chipid_arr) { + kfree(base_addr_arr); return -ENOMEM; + } if (of_property_read_u32_array(node, "chip-id", chipid_arr, nr_chips)) goto error;@@ -143,7 +145,6 @@ static int imc_get_mem_addr_nest(struct device_node *node, return 0; error: - kfree(pmu_ptr->mem_info); kfree(base_addr_arr); kfree(chipid_arr); return -1;@@ -183,8 +184,14 @@ static int imc_pmu_create(struct device_node *parent, int pmu_index, int domain) /* Function to register IMC pmu */ ret = init_imc_pmu(parent, pmu_ptr, pmu_index); - if (ret) + if (ret) { pr_err("IMC PMU %s Register failed\n", pmu_ptr->pmu.name); + kfree(pmu_ptr->pmu.name); + if (pmu_ptr->domain == IMC_DOMAIN_NEST) + kfree(pmu_ptr->mem_info); + kfree(pmu_ptr); + return ret; + } return 0;