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Subject: Re: [PATCH v2 bpf-next] bpf: Print error message for bpftool cgroup
 show
To:     Hechao Li <hechaol@fb.com>, bpf@vger.kernel.org
Cc:     rdna@fb.com, ast@kernel.org, kernel-team@fb.com
References: <20191224011742.3714301-1-hechaol@fb.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <cc43e37a-2ac3-36fc-e18f-59d42b2e5d8f@iogearbox.net>
Date:   Thu, 26 Dec 2019 10:51:29 +0100
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On 12/24/19 2:17 AM, Hechao Li wrote:
> Currently, when bpftool cgroup show <path> has an error, no error
> message is printed. This is confusing because the user may think the
> result is empty.
> 
> Before the change:
> 
> $ bpftool cgroup show /sys/fs/cgroup
> ID       AttachType      AttachFlags     Name
> $ echo $?
> 255
> 
> After the change:
> $ ./bpftool cgroup show /sys/fs/cgroup
> Error: can't query bpf programs attached to /sys/fs/cgroup: Operation
> not permitted
> 
> v2: Rename check_query_cgroup_progs to cgroup_has_attached_progs
> 
> Signed-off-by: Hechao Li <hechaol@fb.com>

Applied, thanks!