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Date:   Tue, 23 Feb 2021 11:23:29 -0800
From:   Martin KaFai Lau <kafai@fb.com>
To:     Song Liu <songliubraving@fb.com>
CC:     <bpf@vger.kernel.org>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <ast@kernel.org>,
        <daniel@iogearbox.net>, <kernel-team@fb.com>,
        <peterz@infradead.org>, KP Singh <kpsingh@kernel.org>
Subject: Re: [PATCH v4 bpf-next 1/6] bpf: enable task local storage for
 tracing programs
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On Mon, Feb 22, 2021 at 05:20:09PM -0800, Song Liu wrote:
[ ... ]

> diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c
> index e0da0258b732d..2034019966d44 100644
> --- a/kernel/bpf/bpf_task_storage.c
> +++ b/kernel/bpf/bpf_task_storage.c
> @@ -15,7 +15,6 @@
>  #include <linux/bpf_local_storage.h>
>  #include <linux/filter.h>
>  #include <uapi/linux/btf.h>
> -#include <linux/bpf_lsm.h>
>  #include <linux/btf_ids.h>
>  #include <linux/fdtable.h>
>  
> @@ -24,12 +23,8 @@ DEFINE_BPF_STORAGE_CACHE(task_cache);
>  static struct bpf_local_storage __rcu **task_storage_ptr(void *owner)
>  {
>  	struct task_struct *task = owner;
> -	struct bpf_storage_blob *bsb;
>  
> -	bsb = bpf_task(task);
> -	if (!bsb)
> -		return NULL;
task_storage_ptr() no longer returns NULL.  All "!task_storage_ptr(task)"
checks should be removed also.  e.g. In bpf_task_storage_get
and bpf_pid_task_storage_update_elem.

> -	return &bsb->storage;
> +	return &task->bpf_storage;
>  }
>