From: Greg Kroah-Hartman Date: Wed, 2 Nov 2022 01:37:01 +0000 (+0100) Subject: 4.14-stable patches X-Git-Tag: v4.9.332~9 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bbf385bf4e4c309cec22e2104c60a5b343e2050d;p=thirdparty%2Fkernel%2Fstable-queue.git 4.14-stable patches added patches: can-rcar_canfd-rcar_canfd_handle_global_receive-fix-irq-storm-on-global-fifo-receive.patch --- diff --git a/queue-4.14/can-rcar_canfd-rcar_canfd_handle_global_receive-fix-irq-storm-on-global-fifo-receive.patch b/queue-4.14/can-rcar_canfd-rcar_canfd_handle_global_receive-fix-irq-storm-on-global-fifo-receive.patch new file mode 100644 index 00000000000..2f36676bd36 --- /dev/null +++ b/queue-4.14/can-rcar_canfd-rcar_canfd_handle_global_receive-fix-irq-storm-on-global-fifo-receive.patch @@ -0,0 +1,65 @@ +From 702de2c21eed04c67cefaaedc248ef16e5f6b293 Mon Sep 17 00:00:00 2001 +From: Biju Das +Date: Tue, 25 Oct 2022 16:56:55 +0100 +Subject: can: rcar_canfd: rcar_canfd_handle_global_receive(): fix IRQ storm on global FIFO receive + +From: Biju Das + +commit 702de2c21eed04c67cefaaedc248ef16e5f6b293 upstream. + +We are seeing an IRQ storm on the global receive IRQ line under heavy +CAN bus load conditions with both CAN channels enabled. + +Conditions: + +The global receive IRQ line is shared between can0 and can1, either of +the channels can trigger interrupt while the other channel's IRQ line +is disabled (RFIE). + +When global a receive IRQ interrupt occurs, we mask the interrupt in +the IRQ handler. Clearing and unmasking of the interrupt is happening +in rx_poll(). There is a race condition where rx_poll() unmasks the +interrupt, but the next IRQ handler does not mask the IRQ due to +NAPIF_STATE_MISSED flag (e.g.: can0 RX FIFO interrupt is disabled and +can1 is triggering RX interrupt, the delay in rx_poll() processing +results in setting NAPIF_STATE_MISSED flag) leading to an IRQ storm. + +This patch fixes the issue by checking IRQ active and enabled before +handling the IRQ on a particular channel. + +Fixes: dd3bd23eb438 ("can: rcar_canfd: Add Renesas R-Car CAN FD driver") +Suggested-by: Marc Kleine-Budde +Signed-off-by: Biju Das +Link: https://lore.kernel.org/all/20221025155657.1426948-2-biju.das.jz@bp.renesas.com +Cc: stable@vger.kernel.org +[mkl: adjust commit message] +Signed-off-by: Marc Kleine-Budde +[biju: removed gpriv from RCANFD_RFCC_RFIE macro] +Signed-off-by: Biju Das +Signed-off-by: Greg Kroah-Hartman +--- + drivers/net/can/rcar/rcar_canfd.c | 6 ++++-- + 1 file changed, 4 insertions(+), 2 deletions(-) + +--- a/drivers/net/can/rcar/rcar_canfd.c ++++ b/drivers/net/can/rcar/rcar_canfd.c +@@ -1079,7 +1079,7 @@ static irqreturn_t rcar_canfd_global_int + struct rcar_canfd_global *gpriv = dev_id; + struct net_device *ndev; + struct rcar_canfd_channel *priv; +- u32 sts, gerfl; ++ u32 sts, cc, gerfl; + u32 ch, ridx; + + /* Global error interrupts still indicate a condition specific +@@ -1097,7 +1097,9 @@ static irqreturn_t rcar_canfd_global_int + + /* Handle Rx interrupts */ + sts = rcar_canfd_read(priv->base, RCANFD_RFSTS(ridx)); +- if (likely(sts & RCANFD_RFSTS_RFIF)) { ++ cc = rcar_canfd_read(priv->base, RCANFD_RFCC(ridx)); ++ if (likely(sts & RCANFD_RFSTS_RFIF && ++ cc & RCANFD_RFCC_RFIE)) { + if (napi_schedule_prep(&priv->napi)) { + /* Disable Rx FIFO interrupts */ + rcar_canfd_clear_bit(priv->base, diff --git a/queue-4.14/series b/queue-4.14/series index 5b347c09528..a06b1f3183a 100644 --- a/queue-4.14/series +++ b/queue-4.14/series @@ -57,3 +57,4 @@ alsa-aoa-i2sbus-fix-possible-memory-leak-in-i2sbus_a.patch alsa-aoa-fix-i2s-device-accounting.patch openvswitch-switch-from-warn-to-pr_warn.patch net-ehea-fix-possible-memory-leak-in-ehea_register_p.patch +can-rcar_canfd-rcar_canfd_handle_global_receive-fix-irq-storm-on-global-fifo-receive.patch