在 2022年06月12日 00:34, Paul E. McKenney 写道:
> On Sat, Jun 11, 2022 at 05:30:55PM +0800, Li Qiong wrote:
>> Add warning when these functions (eg:kmalloc,vmalloc) fail, handle the
>> failure.
>>
>> Signed-off-by: Li Qiong <liqiong@xxxxxxxxxxxx>
> Good catch, thank you! However...
>
>> ---
>> kernel/rcu/rcutorture.c | 8 ++++++++
>> 1 file changed, 8 insertions(+)
>>
>> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
>> index 7120165a9342..97f90e304ae3 100644
>> --- a/kernel/rcu/rcutorture.c
>> +++ b/kernel/rcu/rcutorture.c
>> @@ -1991,6 +1991,10 @@ static void rcu_torture_mem_dump_obj(void)
>>
>> kcp = kmem_cache_create("rcuscale", 136, 8, SLAB_STORE_USER, NULL);
> As long as we are checking, why not also check this one?
>
> Thanx, Paul
Hi Paul,
Yes, the kmem_cache_create would fail too.
I searched "kernel" directory, found that It seems all the code just check kmem_cache_alloc()，
So, I ignored kmem_cache_create() . I will submit a v2 patch.
Thanks,
Li Qiong
>
>> rhp = kmem_cache_alloc(kcp, GFP_KERNEL);
>> + if (WARN_ON_ONCE(!rhp)) {
>> + kmem_cache_destroy(kcp);
>> + return;
>> + }
>> pr_alert("mem_dump_obj() slab test: rcu_torture_stats = %px, &rhp = %px, rhp = %px, &z = %px\n", stats_task, &rhp, rhp, &z);
>> pr_alert("mem_dump_obj(ZERO_SIZE_PTR):");
>> mem_dump_obj(ZERO_SIZE_PTR);
>> @@ -2007,6 +2011,8 @@ static void rcu_torture_mem_dump_obj(void)
>> kmem_cache_free(kcp, rhp);
>> kmem_cache_destroy(kcp);
>> rhp = kmalloc(sizeof(*rhp), GFP_KERNEL);
>> + if (WARN_ON_ONCE(!rhp))
>> + return;
>> pr_alert("mem_dump_obj() kmalloc test: rcu_torture_stats = %px, &rhp = %px, rhp = %px\n", stats_task, &rhp, rhp);
>> pr_alert("mem_dump_obj(kmalloc %px):", rhp);
>> mem_dump_obj(rhp);
>> @@ -2014,6 +2020,8 @@ static void rcu_torture_mem_dump_obj(void)
>> mem_dump_obj(&rhp->func);
>> kfree(rhp);
>> rhp = vmalloc(4096);
>> + if (WARN_ON_ONCE(!rhp))
>> + return;
>> pr_alert("mem_dump_obj() vmalloc test: rcu_torture_stats = %px, &rhp = %px, rhp = %px\n", stats_task, &rhp, rhp);
>> pr_alert("mem_dump_obj(vmalloc %px):", rhp);
>> mem_dump_obj(rhp);
>> --
>> 2.11.0
>>
