* Re: [PATCH] workqueue: Fix possible memory leaks in wq_numa_init()
2021-07-19 6:59 [PATCH] workqueue: Fix possible memory leaks in wq_numa_init() Zhen Lei
@ 2021-07-19 8:49 ` Lai Jiangshan
2021-07-21 16:23 ` Tejun Heo
2021-07-22 1:55 ` Lai Jiangshan
2021-07-22 2:05 ` Lai Jiangshan
2 siblings, 1 reply; 7+ messages in thread
From: Lai Jiangshan @ 2021-07-19 8:49 UTC (permalink / raw)
To: Zhen Lei; +Cc: Tejun Heo, linux-kernel
Hello, Tejun
I think it would be better to fix it.
There have been several tries, sorted by date:
https://lore.kernel.org/lkml/1418379595-6281-2-git-send-email-laijs@cn.fujitsu.com/
https://lore.kernel.org/lkml/1442457835-24238-1-git-send-email-xlpang@126.com/
https://lore.kernel.org/lkml/1452170339-26748-3-git-send-email-wanghaibin.wang@huawei.com/
https://lore.kernel.org/lkml/1533518439-3982-1-git-send-email-wang.yi59@zte.com.cn/
And this one.
Thanks
Lai
On Mon, Jul 19, 2021 at 3:00 PM Zhen Lei <thunder.leizhen@huawei.com> wrote:
>
> In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
> previously allocated memories are not released. Doing this before
> allocating memory eliminates memory leaks.
>
> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> ---
> kernel/workqueue.c | 19 ++++++++++---------
> 1 file changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 50142fc08902..6aa0ba582d15 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -5896,6 +5896,14 @@ static void __init wq_numa_init(void)
> return;
> }
>
> + for_each_possible_cpu(cpu) {
> + if (WARN_ON(cpu_to_node(cpu) == NUMA_NO_NODE)) {
> + pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> + /* happens iff arch is bonkers, let's just proceed */
> + return;
> + }
> + }
> +
> wq_update_unbound_numa_attrs_buf = alloc_workqueue_attrs();
> BUG_ON(!wq_update_unbound_numa_attrs_buf);
>
> @@ -5907,18 +5915,11 @@ static void __init wq_numa_init(void)
> tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
> BUG_ON(!tbl);
>
> - for_each_node(node)
> + for_each_node(node) {
> BUG_ON(!zalloc_cpumask_var_node(&tbl[node], GFP_KERNEL,
> node_online(node) ? node : NUMA_NO_NODE));
>
> - for_each_possible_cpu(cpu) {
> - node = cpu_to_node(cpu);
> - if (WARN_ON(node == NUMA_NO_NODE)) {
> - pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> - /* happens iff arch is bonkers, let's just proceed */
> - return;
> - }
> - cpumask_set_cpu(cpu, tbl[node]);
> + cpumask_copy(tbl[node], cpumask_of_node(node));
> }
>
> wq_numa_possible_cpumask = tbl;
> --
> 2.25.1
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH] workqueue: Fix possible memory leaks in wq_numa_init()
2021-07-19 6:59 [PATCH] workqueue: Fix possible memory leaks in wq_numa_init() Zhen Lei
2021-07-19 8:49 ` Lai Jiangshan
@ 2021-07-22 1:55 ` Lai Jiangshan
2021-07-22 2:37 ` Leizhen (ThunderTown)
2021-07-22 2:05 ` Lai Jiangshan
2 siblings, 1 reply; 7+ messages in thread
From: Lai Jiangshan @ 2021-07-22 1:55 UTC (permalink / raw)
To: Zhen Lei; +Cc: Tejun Heo, linux-kernel
On Mon, Jul 19, 2021 at 3:00 PM Zhen Lei <thunder.leizhen@huawei.com> wrote:
>
> In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
> previously allocated memories are not released. Doing this before
> allocating memory eliminates memory leaks.
>
> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> ---
> kernel/workqueue.c | 19 ++++++++++---------
> 1 file changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 50142fc08902..6aa0ba582d15 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -5896,6 +5896,14 @@ static void __init wq_numa_init(void)
> return;
> }
>
> + for_each_possible_cpu(cpu) {
> + if (WARN_ON(cpu_to_node(cpu) == NUMA_NO_NODE)) {
> + pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> + /* happens iff arch is bonkers, let's just proceed */
> + return;
> + }
> + }
> +
> wq_update_unbound_numa_attrs_buf = alloc_workqueue_attrs();
> BUG_ON(!wq_update_unbound_numa_attrs_buf);
>
> @@ -5907,18 +5915,11 @@ static void __init wq_numa_init(void)
> tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
> BUG_ON(!tbl);
>
> - for_each_node(node)
> + for_each_node(node) {
> BUG_ON(!zalloc_cpumask_var_node(&tbl[node], GFP_KERNEL,
> node_online(node) ? node : NUMA_NO_NODE));
>
> - for_each_possible_cpu(cpu) {
> - node = cpu_to_node(cpu);
> - if (WARN_ON(node == NUMA_NO_NODE)) {
> - pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> - /* happens iff arch is bonkers, let's just proceed */
> - return;
> - }
> - cpumask_set_cpu(cpu, tbl[node]);
> + cpumask_copy(tbl[node], cpumask_of_node(node));
It is incorrect. cpumask_of_node(node) is the online cpumask of the node, not
the possible cpumask of the node that we are interested in.
If the NUMA subsystem provided something like cpumask_possible_of_node(node),
we wouldn't need wq_numa_possible_cpumask.
Please keep "cpumask_copy(tbl[node], cpumask_of_node(node));" as before.
> }
>
> wq_numa_possible_cpumask = tbl;
> --
> 2.25.1
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH] workqueue: Fix possible memory leaks in wq_numa_init()
2021-07-22 1:55 ` Lai Jiangshan
@ 2021-07-22 2:37 ` Leizhen (ThunderTown)
0 siblings, 0 replies; 7+ messages in thread
From: Leizhen (ThunderTown) @ 2021-07-22 2:37 UTC (permalink / raw)
To: Lai Jiangshan; +Cc: Tejun Heo, linux-kernel
On 2021/7/22 9:55, Lai Jiangshan wrote:
> On Mon, Jul 19, 2021 at 3:00 PM Zhen Lei <thunder.leizhen@huawei.com> wrote:
>>
>> In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
>> previously allocated memories are not released. Doing this before
>> allocating memory eliminates memory leaks.
>>
>> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
>> ---
>> kernel/workqueue.c | 19 ++++++++++---------
>> 1 file changed, 10 insertions(+), 9 deletions(-)
>>
>> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
>> index 50142fc08902..6aa0ba582d15 100644
>> --- a/kernel/workqueue.c
>> +++ b/kernel/workqueue.c
>> @@ -5896,6 +5896,14 @@ static void __init wq_numa_init(void)
>> return;
>> }
>>
>> + for_each_possible_cpu(cpu) {
>> + if (WARN_ON(cpu_to_node(cpu) == NUMA_NO_NODE)) {
>> + pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
>> + /* happens iff arch is bonkers, let's just proceed */
>> + return;
>> + }
>> + }
>> +
>> wq_update_unbound_numa_attrs_buf = alloc_workqueue_attrs();
>> BUG_ON(!wq_update_unbound_numa_attrs_buf);
>>
>> @@ -5907,18 +5915,11 @@ static void __init wq_numa_init(void)
>> tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
>> BUG_ON(!tbl);
>>
>> - for_each_node(node)
>> + for_each_node(node) {
>> BUG_ON(!zalloc_cpumask_var_node(&tbl[node], GFP_KERNEL,
>> node_online(node) ? node : NUMA_NO_NODE));
>>
>> - for_each_possible_cpu(cpu) {
>> - node = cpu_to_node(cpu);
>> - if (WARN_ON(node == NUMA_NO_NODE)) {
>> - pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
>> - /* happens iff arch is bonkers, let's just proceed */
>> - return;
>> - }
>> - cpumask_set_cpu(cpu, tbl[node]);
>> + cpumask_copy(tbl[node], cpumask_of_node(node));
>
> It is incorrect. cpumask_of_node(node) is the online cpumask of the node, not
> the possible cpumask of the node that we are interested in.
>
> If the NUMA subsystem provided something like cpumask_possible_of_node(node),
> we wouldn't need wq_numa_possible_cpumask.
>
> Please keep "cpumask_copy(tbl[node], cpumask_of_node(node));" as before.
OK，thanks.
>
>> }
>>
>> wq_numa_possible_cpumask = tbl;
>> --
>> 2.25.1
>>
> .
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] workqueue: Fix possible memory leaks in wq_numa_init()
2021-07-19 6:59 [PATCH] workqueue: Fix possible memory leaks in wq_numa_init() Zhen Lei
2021-07-19 8:49 ` Lai Jiangshan
2021-07-22 1:55 ` Lai Jiangshan
@ 2021-07-22 2:05 ` Lai Jiangshan
2021-07-22 2:44 ` Leizhen (ThunderTown)
2 siblings, 1 reply; 7+ messages in thread
From: Lai Jiangshan @ 2021-07-22 2:05 UTC (permalink / raw)
To: Zhen Lei; +Cc: Tejun Heo, linux-kernel
Please ignore my previous email which included/copied a wrong line of code.
On Thu, Jul 22, 2021 at 12:23 AM Tejun Heo <tj@kernel.org> wrote:
> Yeah, idk. It's not an actual bug tho. Maybe we should just add a comment.
> Which version do you like the best?
I hope Zhen Lei continues to refine his version. I think he is still
working on it.
On Mon, Jul 19, 2021 at 3:00 PM Zhen Lei <thunder.leizhen@huawei.com> wrote:
>
> In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
> previously allocated memories are not released. Doing this before
> allocating memory eliminates memory leaks.
>
> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> ---
> kernel/workqueue.c | 19 ++++++++++---------
> 1 file changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> index 50142fc08902..6aa0ba582d15 100644
> --- a/kernel/workqueue.c
> +++ b/kernel/workqueue.c
> @@ -5896,6 +5896,14 @@ static void __init wq_numa_init(void)
> return;
> }
>
> + for_each_possible_cpu(cpu) {
> + if (WARN_ON(cpu_to_node(cpu) == NUMA_NO_NODE)) {
> + pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> + /* happens iff arch is bonkers, let's just proceed */
I don't think this comment is still needed.
> + return;
> + }
> + }
> +
> wq_update_unbound_numa_attrs_buf = alloc_workqueue_attrs();
> BUG_ON(!wq_update_unbound_numa_attrs_buf);
>
> @@ -5907,18 +5915,11 @@ static void __init wq_numa_init(void)
> tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
> BUG_ON(!tbl);
>
> - for_each_node(node)
> + for_each_node(node) {
> BUG_ON(!zalloc_cpumask_var_node(&tbl[node], GFP_KERNEL,
> node_online(node) ? node : NUMA_NO_NODE));
>
> - for_each_possible_cpu(cpu) {
> - node = cpu_to_node(cpu);
> - if (WARN_ON(node == NUMA_NO_NODE)) {
> - pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
> - /* happens iff arch is bonkers, let's just proceed */
> - return;
> - }
> - cpumask_set_cpu(cpu, tbl[node]);
> + cpumask_copy(tbl[node], cpumask_of_node(node));
It is incorrect. cpumask_of_node(node) is the online cpumask of the node, not
the possible cpumask of the node that we are interested in.
If the NUMA subsystem provided something like cpumask_possible_of_node(node),
we wouldn't need wq_numa_possible_cpumask.
Please keep "for_each_possible_cpu(cpu)" loop and
"cpumask_set_cpu(cpu, tbl[node]);"
> }
>
> wq_numa_possible_cpumask = tbl;
> --
> 2.25.1
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH] workqueue: Fix possible memory leaks in wq_numa_init()
2021-07-22 2:05 ` Lai Jiangshan
@ 2021-07-22 2:44 ` Leizhen (ThunderTown)
0 siblings, 0 replies; 7+ messages in thread
From: Leizhen (ThunderTown) @ 2021-07-22 2:44 UTC (permalink / raw)
To: Lai Jiangshan; +Cc: Tejun Heo, linux-kernel
On 2021/7/22 10:05, Lai Jiangshan wrote:
> Please ignore my previous email which included/copied a wrong line of code.
>
> On Thu, Jul 22, 2021 at 12:23 AM Tejun Heo <tj@kernel.org> wrote:
>> Yeah, idk. It's not an actual bug tho. Maybe we should just add a comment.
>> Which version do you like the best?
>
> I hope Zhen Lei continues to refine his version. I think he is still
> working on it.
Yes, I'm inclined to fix it, too. The tools aren't that smart, and handling
false positives is an annoyance.
>
> On Mon, Jul 19, 2021 at 3:00 PM Zhen Lei <thunder.leizhen@huawei.com> wrote:
>>
>> In error handling branch "if (WARN_ON(node == NUMA_NO_NODE))", the
>> previously allocated memories are not released. Doing this before
>> allocating memory eliminates memory leaks.
>>
>> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
>> ---
>> kernel/workqueue.c | 19 ++++++++++---------
>> 1 file changed, 10 insertions(+), 9 deletions(-)
>>
>> diff --git a/kernel/workqueue.c b/kernel/workqueue.c
>> index 50142fc08902..6aa0ba582d15 100644
>> --- a/kernel/workqueue.c
>> +++ b/kernel/workqueue.c
>> @@ -5896,6 +5896,14 @@ static void __init wq_numa_init(void)
>> return;
>> }
>>
>> + for_each_possible_cpu(cpu) {
>> + if (WARN_ON(cpu_to_node(cpu) == NUMA_NO_NODE)) {
>> + pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
>
>
>> + /* happens iff arch is bonkers, let's just proceed */
>
> I don't think this comment is still needed.
OK, I will remove it.
>
>> + return;
>> + }
>> + }
>> +
>> wq_update_unbound_numa_attrs_buf = alloc_workqueue_attrs();
>> BUG_ON(!wq_update_unbound_numa_attrs_buf);
>>
>> @@ -5907,18 +5915,11 @@ static void __init wq_numa_init(void)
>> tbl = kcalloc(nr_node_ids, sizeof(tbl[0]), GFP_KERNEL);
>> BUG_ON(!tbl);
>>
>> - for_each_node(node)
>> + for_each_node(node) {
>> BUG_ON(!zalloc_cpumask_var_node(&tbl[node], GFP_KERNEL,
>> node_online(node) ? node : NUMA_NO_NODE));
>>
>> - for_each_possible_cpu(cpu) {
>> - node = cpu_to_node(cpu);
>> - if (WARN_ON(node == NUMA_NO_NODE)) {
>> - pr_warn("workqueue: NUMA node mapping not available for cpu%d, disabling NUMA support\n", cpu);
>> - /* happens iff arch is bonkers, let's just proceed */
>> - return;
>> - }
>> - cpumask_set_cpu(cpu, tbl[node]);
>> + cpumask_copy(tbl[node], cpumask_of_node(node));
>
> It is incorrect. cpumask_of_node(node) is the online cpumask of the node, not
> the possible cpumask of the node that we are interested in.
>
> If the NUMA subsystem provided something like cpumask_possible_of_node(node),
> we wouldn't need wq_numa_possible_cpumask.
>
> Please keep "for_each_possible_cpu(cpu)" loop and
> "cpumask_set_cpu(cpu, tbl[node]);"
OK.
>
>> }
>>
>> wq_numa_possible_cpumask = tbl;
>> --
>> 2.25.1
>>
> .
>
^ permalink raw reply [flat|nested] 7+ messages in thread