| Message ID | b28b55a639002a56b77c0651a4122ebede041936.1670421354.git.lorenzo@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | fix possible deadlock during WED attach | expand |
On Wed, Dec 07, 2022 at 03:04:55PM +0100, Lorenzo Bianconi wrote: > Introduce __mtk_wed_detach() in order to avoid a deadlock in > mtk_wed_attach routine if mtk_wed_wo_init fails since both > mtk_wed_attach and mtk_wed_detach run holding hw_lock mutex. > > Fixes: 4c5de09eb0d0 ("net: ethernet: mtk_wed: add configure wed wo support") > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > --- > drivers/net/ethernet/mediatek/mtk_wed.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/ethernet/mediatek/mtk_wed.c > index 4ef23eadd69e..a6271449617f 100644 > --- a/drivers/net/ethernet/mediatek/mtk_wed.c > +++ b/drivers/net/ethernet/mediatek/mtk_wed.c > @@ -577,12 +577,10 @@ mtk_wed_deinit(struct mtk_wed_device *dev) > } > Thanks, Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
diff --git a/drivers/net/ethernet/mediatek/mtk_wed.c b/drivers/net/ethernet/mediatek/mtk_wed.c index 4ef23eadd69e..a6271449617f 100644 --- a/drivers/net/ethernet/mediatek/mtk_wed.c +++ b/drivers/net/ethernet/mediatek/mtk_wed.c @@ -577,12 +577,10 @@ mtk_wed_deinit(struct mtk_wed_device *dev) } static void -mtk_wed_detach(struct mtk_wed_device *dev) +__mtk_wed_detach(struct mtk_wed_device *dev) { struct mtk_wed_hw *hw = dev->hw; - mutex_lock(&hw_lock); - mtk_wed_deinit(dev); mtk_wdma_rx_reset(dev); @@ -615,6 +613,13 @@ mtk_wed_detach(struct mtk_wed_device *dev) module_put(THIS_MODULE); hw->wed_dev = NULL; +} + +static void +mtk_wed_detach(struct mtk_wed_device *dev) +{ + mutex_lock(&hw_lock); + __mtk_wed_detach(dev); mutex_unlock(&hw_lock); } @@ -1497,8 +1502,10 @@ mtk_wed_attach(struct mtk_wed_device *dev) ret = mtk_wed_wo_init(hw); } out: - if (ret) - mtk_wed_detach(dev); + if (ret) { + dev_err(dev->hw->dev, "failed to attach wed device\n"); + __mtk_wed_detach(dev); + } unlock: mutex_unlock(&hw_lock);
Introduce __mtk_wed_detach() in order to avoid a deadlock in mtk_wed_attach routine if mtk_wed_wo_init fails since both mtk_wed_attach and mtk_wed_detach run holding hw_lock mutex. Fixes: 4c5de09eb0d0 ("net: ethernet: mtk_wed: add configure wed wo support") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- drivers/net/ethernet/mediatek/mtk_wed.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)