From: Valentin Longchamp valentin@longchamp.me
[ Upstream commit 79dde73cf9bcf1dd317a2667f78b758e9fe139ed ]
ugeth_quiesce/activate are used to halt the controller when there is a link change that requires to reconfigure the mac.
The previous implementation called netif_device_detach(). This however causes the initial activation of the netdevice to fail precisely because it's detached. For details, see [1].
A possible workaround was the revert of commit net: linkwatch: add check for netdevice being present to linkwatch_do_dev However, the check introduced in the above commit is correct and shall be kept.
The netif_device_detach() is thus replaced with netif_tx_stop_all_queues() that prevents any tranmission. This allows to perform mac config change required by the link change, without detaching the corresponding netdevice and thus not preventing its initial activation.
[1] https://lists.openwall.net/netdev/2020/01/08/201
Signed-off-by: Valentin Longchamp valentin@longchamp.me Acked-by: Matteo Ghidoni matteo.ghidoni@ch.abb.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/freescale/ucc_geth.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/freescale/ucc_geth.c b/drivers/net/ethernet/freescale/ucc_geth.c index f839fa94ebdd..d3b8ce734c1b 100644 --- a/drivers/net/ethernet/freescale/ucc_geth.c +++ b/drivers/net/ethernet/freescale/ucc_geth.c @@ -42,6 +42,7 @@ #include <soc/fsl/qe/ucc.h> #include <soc/fsl/qe/ucc_fast.h> #include <asm/machdep.h> +#include <net/sch_generic.h>
#include "ucc_geth.h"
@@ -1548,11 +1549,8 @@ static int ugeth_disable(struct ucc_geth_private *ugeth, enum comm_dir mode)
static void ugeth_quiesce(struct ucc_geth_private *ugeth) { - /* Prevent any further xmits, plus detach the device. */ - netif_device_detach(ugeth->ndev); - - /* Wait for any current xmits to finish. */ - netif_tx_disable(ugeth->ndev); + /* Prevent any further xmits */ + netif_tx_stop_all_queues(ugeth->ndev);
/* Disable the interrupt to avoid NAPI rescheduling. */ disable_irq(ugeth->ug_info->uf_info.irq); @@ -1565,7 +1563,10 @@ static void ugeth_activate(struct ucc_geth_private *ugeth) { napi_enable(&ugeth->napi); enable_irq(ugeth->ug_info->uf_info.irq); - netif_device_attach(ugeth->ndev); + + /* allow to xmit again */ + netif_tx_wake_all_queues(ugeth->ndev); + __netdev_watchdog_up(ugeth->ndev); }
/* Called every time the controller might need to be made