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References: <20220509231901.3852573-1-cmllamas@google.com>
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From:   Todd Kjos <tkjos@google.com>
Date:   Mon, 9 May 2022 16:24:15 -0700
Message-ID: <CAHRSSExZrAEZuxska3kwpXCCv+p2+W_UPYCWbKUAswBjy97iBQ@mail.gmail.com>
Subject: Re: [PATCH] binder: fix printk format for commands
To:     Carlos Llamas <cmllamas@google.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOlZw==?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Christian Brauner <brauner@kernel.org>,
        Joel Fernandes <joel@joelfernandes.org>,
        Hridya Valsaraju <hridya@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        kernel-team@android.com, linux-kernel@vger.kernel.org
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On Mon, May 9, 2022 at 4:19 PM Carlos Llamas <cmllamas@google.com> wrote:
>
> Make sure we use unsigned format specifier %u for binder commands as
> most of them are encoded above INT_MAX. This prevents negative values
> when logging them as in the following case:
>
> [  211.895781] binder: 8668:8668 BR_REPLY 258949 0:0, cmd -2143260157 size 0-0 ptr 0000006e766a8000-0000006e766a8000
>
> Signed-off-by: Carlos Llamas <cmllamas@google.com>

Acked-by: Todd Kjos <tkjos@google.com>

> ---
>  drivers/android/binder.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index f3b639e89dd8..b4b0e4489bef 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -3984,7 +3984,7 @@ static int binder_thread_write(struct binder_proc *proc,
>                 } break;
>
>                 default:
> -                       pr_err("%d:%d unknown command %d\n",
> +                       pr_err("%d:%d unknown command %u\n",
>                                proc->pid, thread->pid, cmd);
>                         return -EINVAL;
>                 }
> @@ -4490,7 +4490,7 @@ static int binder_thread_read(struct binder_proc *proc,
>                 trace_binder_transaction_received(t);
>                 binder_stat_br(proc, thread, cmd);
>                 binder_debug(BINDER_DEBUG_TRANSACTION,
> -                            "%d:%d %s %d %d:%d, cmd %d size %zd-%zd ptr %016llx-%016llx\n",
> +                            "%d:%d %s %d %d:%d, cmd %u size %zd-%zd ptr %016llx-%016llx\n",
>                              proc->pid, thread->pid,
>                              (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
>                                 (cmd == BR_TRANSACTION_SEC_CTX) ?
> --
> 2.36.0.512.ge40c2bad7a-goog
>