From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx48LO21TzmLUxB3aiEvMIQ0dJqLl3hKd5zzCvXISvxnSJw+V+sX34HImey458Y56S2gRvZ2o ARC-Seal: i=1; a=rsa-sha256; t=1522168988; cv=none; d=google.com; s=arc-20160816; b=X2ZpSmq7yRtm6vjXVj0SqtVqJmixn7t7nTYKZIhS7K3AeSHI+jV4ZJaNnf2Vixw0li ggvS1B2oi4dKYkAZ8KTdVmzBKMpjfTcu7A6a1NUVLMh/RQgfdprJO/qnii3KBeFm+9rg tGqSRgGB3tOdPJVb4af+6VrTEHEk00N+RwQt+pgvaUpr75IjiABDecq0kYIkTekCX+Tv R+kUfKioAsdNooQuue7tJZEPngNTmvgByYWXX0msY8dQp9JWuIsrd2Q/Zcx2/CiP+SvO eCRJVEA1wVsUPhezAUi/XwqzPq4A7msdHYpnDT9+uIKQo2lhRzHjBjTT5VlLNrj+EOE1 iXmA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=HMkOJDtxNU5nnMeDskalk77LAPtCLZ1TIPUGZF4MKoA=; b=URpFPUUmO2TG23PHPWBegeMI++zxIEZyZZ9W2zWVFSuqYV2Sb89XSycP63N3nRvCgG n1rMDH3Z5qzmEOUW6NgHn5gasI9wMnyRsRNIJ2OmYbsGPIwobgF74CwP20fMPWTDCtYJ QaBfuTMplNpnW2h8VxASwX8om2G4t4kbJ5rxHxCWI7lKJeaCZn/IZizweWgCY6YKLGvV gikY4lBlekuVS58nE2/+wiOgJB4ZHC/M05FA6VbI5Y0munnGclNpbukb1F72i7NpfoEg lAyHm/0U8AGRgEdoA9GFSA/jCRp8OeIoTz/H+D/wCk4pvdF59wO5bYOb5dXR4raf9DFa eSEQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.61.202 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Diana Burgess , Stephane Grosjean , Marc Kleine-Budde Subject: [PATCH 4.15 075/105] can: peak/pcie_fd: fix echo_skb is occupied! bug Date: Tue, 27 Mar 2018 18:27:55 +0200 Message-Id: <20180327162802.559928021@linuxfoundation.org> X-Mailer: git-send-email 2.16.3 In-Reply-To: <20180327162757.813009222@linuxfoundation.org> References: <20180327162757.813009222@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1596109471989770116?= X-GMAIL-MSGID: =?utf-8?q?1596109869274487449?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephane Grosjean commit e6048a00cfd0863d32f53b226e0b9a3633fc3332 upstream. This patch makes atomic the handling of the linux-can echo_skb array and the network tx queue. This prevents from the "BUG! echo_skb is occupied!" message to be printed by the linux-can core, in SMP environments. Reported-by: Diana Burgess Signed-off-by: Stephane Grosjean Cc: linux-stable Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/peak_canfd/peak_canfd.c | 12 ++++++------ drivers/net/can/peak_canfd/peak_pciefd_main.c | 8 ++++++-- 2 files changed, 12 insertions(+), 8 deletions(-) --- a/drivers/net/can/peak_canfd/peak_canfd.c +++ b/drivers/net/can/peak_canfd/peak_canfd.c @@ -262,7 +262,6 @@ static int pucan_handle_can_rx(struct pe spin_lock_irqsave(&priv->echo_lock, flags); can_get_echo_skb(priv->ndev, msg->client); - spin_unlock_irqrestore(&priv->echo_lock, flags); /* count bytes of the echo instead of skb */ stats->tx_bytes += cf_len; @@ -271,6 +270,7 @@ static int pucan_handle_can_rx(struct pe /* restart tx queue (a slot is free) */ netif_wake_queue(priv->ndev); + spin_unlock_irqrestore(&priv->echo_lock, flags); return 0; } @@ -726,11 +726,6 @@ static netdev_tx_t peak_canfd_start_xmit */ should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]); - spin_unlock_irqrestore(&priv->echo_lock, flags); - - /* write the skb on the interface */ - priv->write_tx_msg(priv, msg); - /* stop network tx queue if not enough room to save one more msg too */ if (priv->can.ctrlmode & CAN_CTRLMODE_FD) should_stop_tx_queue |= (room_left < @@ -742,6 +737,11 @@ static netdev_tx_t peak_canfd_start_xmit if (should_stop_tx_queue) netif_stop_queue(ndev); + spin_unlock_irqrestore(&priv->echo_lock, flags); + + /* write the skb on the interface */ + priv->write_tx_msg(priv, msg); + return NETDEV_TX_OK; } --- a/drivers/net/can/peak_canfd/peak_pciefd_main.c +++ b/drivers/net/can/peak_canfd/peak_pciefd_main.c @@ -349,8 +349,12 @@ static irqreturn_t pciefd_irq_handler(in priv->tx_pages_free++; spin_unlock_irqrestore(&priv->tx_lock, flags); - /* wake producer up */ - netif_wake_queue(priv->ucan.ndev); + /* wake producer up (only if enough room in echo_skb array) */ + spin_lock_irqsave(&priv->ucan.echo_lock, flags); + if (!priv->ucan.can.echo_skb[priv->ucan.echo_idx]) + netif_wake_queue(priv->ucan.ndev); + + spin_unlock_irqrestore(&priv->ucan.echo_lock, flags); } /* re-enable Rx DMA transfer for this CAN */