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References: <20210512133407.52330-1-szymon.janc@codecoup.pl>
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From:   Kai Krakow <kai@kaishome.de>
Date:   Wed, 12 May 2021 19:04:01 +0200
Message-ID: <CAC2ZOYvax0WGO7wMzbPXQMGb2NDouAF6XRgd5TH+h-f6uWvhtg@mail.gmail.com>
Subject: Re: [PATCH] Bluetooth: Remove spurious error message
To:     Szymon Janc <szymon.janc@codecoup.pl>
Cc:     linux-bluetooth@vger.kernel.org, stable@vger.kernel.org
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Hi Szymon!

Am Mi., 12. Mai 2021 um 15:34 Uhr schrieb Szymon Janc <szymon.janc@codecoup.pl>:
>
> Even with rate limited reporting this is very spammy and since
> it is remote device that is providing bogus data there is no
> need to report this as error.
>
[...]
> [72464.546319] Bluetooth: hci0: advertising data len corrected
> [72464.857318] Bluetooth: hci0: advertising data len corrected
> [72465.163332] Bluetooth: hci0: advertising data len corrected
> [72465.278331] Bluetooth: hci0: advertising data len corrected
> [72465.432323] Bluetooth: hci0: advertising data len corrected
> [72465.891334] Bluetooth: hci0: advertising data len corrected
> [72466.045334] Bluetooth: hci0: advertising data len corrected
> [72466.197321] Bluetooth: hci0: advertising data len corrected
> [72466.340318] Bluetooth: hci0: advertising data len corrected
> [72466.498335] Bluetooth: hci0: advertising data len corrected
> [72469.803299] bt_err_ratelimited: 10 callbacks suppressed
>
> Signed-off-by: Szymon Janc <szymon.janc@codecoup.pl>
> Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=203753
> Cc: stable@vger.kernel.org
> ---
>  net/bluetooth/hci_event.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 5e99968939ce..abdc44dc0b2f 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -5476,8 +5476,6 @@ static void process_adv_report(struct hci_dev *hdev, u8 type, bdaddr_t *bdaddr,
>
>         /* Adjust for actual length */
>         if (len != real_len) {
> -               bt_dev_err_ratelimited(hdev, "advertising data len corrected %u -> %u",
> -                                      len, real_len);
>                 len = real_len;
>         }

This renders the "if" quite useless since it now always ensures len =
real_len and nothing else. At this point, the "if" can be removed, and
len can be set unconditionally. Depending on the further context of
the patch, destinction between real_len and len may not be needed at
all and real_len could be renamed to len, ditching the unused original
which is potentially bogus data anyways according to your commit
description.

Regards,
Kai