| Message ID | 20201211110317.17061-1-o.rempel@pengutronix.de (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [v2] net: dsa: qca: ar9331: fix sleeping function called from invalid context bug | expand |
On Fri, Dec 11, 2020 at 12:03:17PM +0100, Oleksij Rempel wrote: > With lockdep enabled, we will get following warning: > > ar9331_switch ethernet.1:10 lan0 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:00] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) > BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935 > in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 18, name: kworker/0:1 > INFO: lockdep is turned off. > irq event stamp: 602 > hardirqs last enabled at (601): [<8073fde0>] _raw_spin_unlock_irq+0x3c/0x80 > hardirqs last disabled at (602): [<8073a4f4>] __schedule+0x184/0x800 > softirqs last enabled at (0): [<80080f60>] copy_process+0x578/0x14c8 > softirqs last disabled at (0): [<00000000>] 0x0 > CPU: 0 PID: 18 Comm: kworker/0:1 Not tainted 5.10.0-rc3-ar9331-00734-g7d644991df0c #31 > Workqueue: events deferred_probe_work_func > Stack : 80980000 80980000 8089ef70 80890000 804b5414 80980000 00000002 80b53728 > 00000000 800d1268 804b5414 ffffffde 00000017 800afe08 81943860 0f5bfc32 > 00000000 00000000 8089ef70 819436c0 ffffffea 00000000 00000000 00000000 > 8194390c 808e353c 0000000f 66657272 80980000 00000000 00000000 80890000 > 804b5414 80980000 00000002 80b53728 00000000 00000000 00000000 80d40000 > ... > Call Trace: > [<80069ce0>] show_stack+0x9c/0x140 > [<800afe08>] ___might_sleep+0x220/0x244 > [<8073bfb0>] __mutex_lock+0x70/0x374 > [<8073c2e0>] mutex_lock_nested+0x2c/0x38 > [<804b5414>] regmap_update_bits_base+0x38/0x8c > [<804ee584>] regmap_update_bits+0x1c/0x28 > [<804ee714>] ar9331_sw_unmask_irq+0x34/0x60 > [<800d91f0>] unmask_irq+0x48/0x70 > [<800d93d4>] irq_startup+0x114/0x11c > [<800d65b4>] __setup_irq+0x4f4/0x6d0 > [<800d68a0>] request_threaded_irq+0x110/0x190 > [<804e3ef0>] phy_request_interrupt+0x4c/0xe4 > [<804df508>] phylink_bringup_phy+0x2c0/0x37c > [<804df7bc>] phylink_of_phy_connect+0x118/0x130 > [<806c1a64>] dsa_slave_create+0x3d0/0x578 > [<806bc4ec>] dsa_register_switch+0x934/0xa20 > [<804eef98>] ar9331_sw_probe+0x34c/0x364 > [<804eb48c>] mdio_probe+0x44/0x70 > [<8049e3b4>] really_probe+0x30c/0x4f4 > [<8049ea10>] driver_probe_device+0x264/0x26c > [<8049bc10>] bus_for_each_drv+0xb4/0xd8 > [<8049e684>] __device_attach+0xe8/0x18c > [<8049ce58>] bus_probe_device+0x48/0xc4 > [<8049db70>] deferred_probe_work_func+0xdc/0xf8 > [<8009ff64>] process_one_work+0x2e4/0x4a0 > [<800a0770>] worker_thread+0x2a8/0x354 > [<800a774c>] kthread+0x16c/0x174 > [<8006306c>] ret_from_kernel_thread+0x14/0x1c > > ar9331_switch ethernet.1:10 lan1 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:02] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) > DSA: tree 0 setup > > To fix it, it is better to move access to MDIO register to the .irq_bus_sync_unlock > call back. > > Fixes: ec6698c272de ("net: dsa: add support for Atheros AR9331 built-in switch") > Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> > --- Just from looking at other irqchip drivers, it seems probably ok to do your I/O from .irq_bus_sync_unlock. Reviewed-by: Vladimir Oltean <olteanv@gmail.com> But I'm a bit concerned about your ar9331_sw_remove method. Is it safe to call these in the following order? irq_domain_remove(priv->irqdomain); mdiobus_unregister(priv->mbus); dsa_unregister_switch(&priv->ds); What if a PHY interrupt occurs after the irqdomain was removed and/or the master MDIO bus was removed, but before dsa_unregister_switch happened, which performed all the phylink teardown? > changes v2: > - fix comment on error > > drivers/net/dsa/qca/ar9331.c | 33 ++++++++++++++++++++++++--------- > 1 file changed, 24 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/dsa/qca/ar9331.c b/drivers/net/dsa/qca/ar9331.c > index e24a99031b80..4d49c5f2b790 100644 > --- a/drivers/net/dsa/qca/ar9331.c > +++ b/drivers/net/dsa/qca/ar9331.c > @@ -159,6 +159,8 @@ struct ar9331_sw_priv { > struct dsa_switch ds; > struct dsa_switch_ops ops; > struct irq_domain *irqdomain; > + u32 irq_mask; > + struct mutex lock_irq; > struct mii_bus *mbus; /* mdio master */ > struct mii_bus *sbus; /* mdio slave */ > struct regmap *regmap; > @@ -520,32 +522,44 @@ static irqreturn_t ar9331_sw_irq(int irq, void *data) > static void ar9331_sw_mask_irq(struct irq_data *d) > { > struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > - struct regmap *regmap = priv->regmap; > - int ret; > > - ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, > - AR9331_SW_GINT_PHY_INT, 0); > - if (ret) > - dev_err(priv->dev, "could not mask IRQ\n"); > + priv->irq_mask = 0; > } > > static void ar9331_sw_unmask_irq(struct irq_data *d) > +{ > + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > + > + priv->irq_mask = AR9331_SW_GINT_PHY_INT; > +} > + > +static void ar9331_sw_irq_bus_lock(struct irq_data *d) > +{ > + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > + > + mutex_lock(&priv->lock_irq); > +} > + > +static void ar9331_sw_irq_bus_sync_unlock(struct irq_data *d) > { > struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > struct regmap *regmap = priv->regmap; > int ret; > > ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, > - AR9331_SW_GINT_PHY_INT, > - AR9331_SW_GINT_PHY_INT); > + AR9331_SW_GINT_PHY_INT, priv->irq_mask); > if (ret) > - dev_err(priv->dev, "could not unmask IRQ\n"); > + dev_err(priv->dev, "failed to change IRQ mask\n"); > + > + mutex_unlock(&priv->lock_irq); > } > > static struct irq_chip ar9331_sw_irq_chip = { > .name = AR9331_SW_NAME, > .irq_mask = ar9331_sw_mask_irq, > .irq_unmask = ar9331_sw_unmask_irq, > + .irq_bus_lock = ar9331_sw_irq_bus_lock, > + .irq_bus_sync_unlock = ar9331_sw_irq_bus_sync_unlock, > }; > > static int ar9331_sw_irq_map(struct irq_domain *domain, unsigned int irq, > @@ -584,6 +598,7 @@ static int ar9331_sw_irq_init(struct ar9331_sw_priv *priv) > return irq ? irq : -EINVAL; > } > > + mutex_init(&priv->lock_irq); > ret = devm_request_threaded_irq(dev, irq, NULL, ar9331_sw_irq, > IRQF_ONESHOT, AR9331_SW_NAME, priv); > if (ret) { > -- > 2.29.2 >
On Sat, Dec 12, 2020 at 03:25:58PM +0200, Vladimir Oltean wrote: > On Fri, Dec 11, 2020 at 12:03:17PM +0100, Oleksij Rempel wrote: > > With lockdep enabled, we will get following warning: > > > > ar9331_switch ethernet.1:10 lan0 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:00] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) > > BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935 > > in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 18, name: kworker/0:1 > > INFO: lockdep is turned off. > > irq event stamp: 602 > > hardirqs last enabled at (601): [<8073fde0>] _raw_spin_unlock_irq+0x3c/0x80 > > hardirqs last disabled at (602): [<8073a4f4>] __schedule+0x184/0x800 > > softirqs last enabled at (0): [<80080f60>] copy_process+0x578/0x14c8 > > softirqs last disabled at (0): [<00000000>] 0x0 > > CPU: 0 PID: 18 Comm: kworker/0:1 Not tainted 5.10.0-rc3-ar9331-00734-g7d644991df0c #31 > > Workqueue: events deferred_probe_work_func > > Stack : 80980000 80980000 8089ef70 80890000 804b5414 80980000 00000002 80b53728 > > 00000000 800d1268 804b5414 ffffffde 00000017 800afe08 81943860 0f5bfc32 > > 00000000 00000000 8089ef70 819436c0 ffffffea 00000000 00000000 00000000 > > 8194390c 808e353c 0000000f 66657272 80980000 00000000 00000000 80890000 > > 804b5414 80980000 00000002 80b53728 00000000 00000000 00000000 80d40000 > > ... > > Call Trace: > > [<80069ce0>] show_stack+0x9c/0x140 > > [<800afe08>] ___might_sleep+0x220/0x244 > > [<8073bfb0>] __mutex_lock+0x70/0x374 > > [<8073c2e0>] mutex_lock_nested+0x2c/0x38 > > [<804b5414>] regmap_update_bits_base+0x38/0x8c > > [<804ee584>] regmap_update_bits+0x1c/0x28 > > [<804ee714>] ar9331_sw_unmask_irq+0x34/0x60 > > [<800d91f0>] unmask_irq+0x48/0x70 > > [<800d93d4>] irq_startup+0x114/0x11c > > [<800d65b4>] __setup_irq+0x4f4/0x6d0 > > [<800d68a0>] request_threaded_irq+0x110/0x190 > > [<804e3ef0>] phy_request_interrupt+0x4c/0xe4 > > [<804df508>] phylink_bringup_phy+0x2c0/0x37c > > [<804df7bc>] phylink_of_phy_connect+0x118/0x130 > > [<806c1a64>] dsa_slave_create+0x3d0/0x578 > > [<806bc4ec>] dsa_register_switch+0x934/0xa20 > > [<804eef98>] ar9331_sw_probe+0x34c/0x364 > > [<804eb48c>] mdio_probe+0x44/0x70 > > [<8049e3b4>] really_probe+0x30c/0x4f4 > > [<8049ea10>] driver_probe_device+0x264/0x26c > > [<8049bc10>] bus_for_each_drv+0xb4/0xd8 > > [<8049e684>] __device_attach+0xe8/0x18c > > [<8049ce58>] bus_probe_device+0x48/0xc4 > > [<8049db70>] deferred_probe_work_func+0xdc/0xf8 > > [<8009ff64>] process_one_work+0x2e4/0x4a0 > > [<800a0770>] worker_thread+0x2a8/0x354 > > [<800a774c>] kthread+0x16c/0x174 > > [<8006306c>] ret_from_kernel_thread+0x14/0x1c > > > > ar9331_switch ethernet.1:10 lan1 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:02] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) > > DSA: tree 0 setup > > > > To fix it, it is better to move access to MDIO register to the .irq_bus_sync_unlock > > call back. > > > > Fixes: ec6698c272de ("net: dsa: add support for Atheros AR9331 built-in switch") > > Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> > > --- > > Just from looking at other irqchip drivers, it seems probably ok to do > your I/O from .irq_bus_sync_unlock. > > Reviewed-by: Vladimir Oltean <olteanv@gmail.com> OK, thx! > But I'm a bit concerned about your ar9331_sw_remove method. Is it safe > to call these in the following order? > > irq_domain_remove(priv->irqdomain); > mdiobus_unregister(priv->mbus); > dsa_unregister_switch(&priv->ds); > > What if a PHY interrupt occurs after the irqdomain was removed and/or > the master MDIO bus was removed, but before dsa_unregister_switch > happened, which performed all the phylink teardown? Good point. It is different bug, i'll send a separate patch for this. > > changes v2: > > - fix comment on error > > > > drivers/net/dsa/qca/ar9331.c | 33 ++++++++++++++++++++++++--------- > > 1 file changed, 24 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/net/dsa/qca/ar9331.c b/drivers/net/dsa/qca/ar9331.c > > index e24a99031b80..4d49c5f2b790 100644 > > --- a/drivers/net/dsa/qca/ar9331.c > > +++ b/drivers/net/dsa/qca/ar9331.c > > @@ -159,6 +159,8 @@ struct ar9331_sw_priv { > > struct dsa_switch ds; > > struct dsa_switch_ops ops; > > struct irq_domain *irqdomain; > > + u32 irq_mask; > > + struct mutex lock_irq; > > struct mii_bus *mbus; /* mdio master */ > > struct mii_bus *sbus; /* mdio slave */ > > struct regmap *regmap; > > @@ -520,32 +522,44 @@ static irqreturn_t ar9331_sw_irq(int irq, void *data) > > static void ar9331_sw_mask_irq(struct irq_data *d) > > { > > struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > > - struct regmap *regmap = priv->regmap; > > - int ret; > > > > - ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, > > - AR9331_SW_GINT_PHY_INT, 0); > > - if (ret) > > - dev_err(priv->dev, "could not mask IRQ\n"); > > + priv->irq_mask = 0; > > } > > > > static void ar9331_sw_unmask_irq(struct irq_data *d) > > +{ > > + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > > + > > + priv->irq_mask = AR9331_SW_GINT_PHY_INT; > > +} > > + > > +static void ar9331_sw_irq_bus_lock(struct irq_data *d) > > +{ > > + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > > + > > + mutex_lock(&priv->lock_irq); > > +} > > + > > +static void ar9331_sw_irq_bus_sync_unlock(struct irq_data *d) > > { > > struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); > > struct regmap *regmap = priv->regmap; > > int ret; > > > > ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, > > - AR9331_SW_GINT_PHY_INT, > > - AR9331_SW_GINT_PHY_INT); > > + AR9331_SW_GINT_PHY_INT, priv->irq_mask); > > if (ret) > > - dev_err(priv->dev, "could not unmask IRQ\n"); > > + dev_err(priv->dev, "failed to change IRQ mask\n"); > > + > > + mutex_unlock(&priv->lock_irq); > > } > > > > static struct irq_chip ar9331_sw_irq_chip = { > > .name = AR9331_SW_NAME, > > .irq_mask = ar9331_sw_mask_irq, > > .irq_unmask = ar9331_sw_unmask_irq, > > + .irq_bus_lock = ar9331_sw_irq_bus_lock, > > + .irq_bus_sync_unlock = ar9331_sw_irq_bus_sync_unlock, > > }; > > > > static int ar9331_sw_irq_map(struct irq_domain *domain, unsigned int irq, > > @@ -584,6 +598,7 @@ static int ar9331_sw_irq_init(struct ar9331_sw_priv *priv) > > return irq ? irq : -EINVAL; > > } > > > > + mutex_init(&priv->lock_irq); > > ret = devm_request_threaded_irq(dev, irq, NULL, ar9331_sw_irq, > > IRQF_ONESHOT, AR9331_SW_NAME, priv); > > if (ret) { > > -- > > 2.29.2 > > > >
Hello: This patch was applied to netdev/net.git (refs/heads/master): On Fri, 11 Dec 2020 12:03:17 +0100 you wrote: > With lockdep enabled, we will get following warning: > > ar9331_switch ethernet.1:10 lan0 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:00] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) > BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935 > in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 18, name: kworker/0:1 > INFO: lockdep is turned off. > irq event stamp: 602 > hardirqs last enabled at (601): [<8073fde0>] _raw_spin_unlock_irq+0x3c/0x80 > hardirqs last disabled at (602): [<8073a4f4>] __schedule+0x184/0x800 > softirqs last enabled at (0): [<80080f60>] copy_process+0x578/0x14c8 > softirqs last disabled at (0): [<00000000>] 0x0 > CPU: 0 PID: 18 Comm: kworker/0:1 Not tainted 5.10.0-rc3-ar9331-00734-g7d644991df0c #31 > Workqueue: events deferred_probe_work_func > Stack : 80980000 80980000 8089ef70 80890000 804b5414 80980000 00000002 80b53728 > 00000000 800d1268 804b5414 ffffffde 00000017 800afe08 81943860 0f5bfc32 > 00000000 00000000 8089ef70 819436c0 ffffffea 00000000 00000000 00000000 > 8194390c 808e353c 0000000f 66657272 80980000 00000000 00000000 80890000 > 804b5414 80980000 00000002 80b53728 00000000 00000000 00000000 80d40000 > ... > Call Trace: > [<80069ce0>] show_stack+0x9c/0x140 > [<800afe08>] ___might_sleep+0x220/0x244 > [<8073bfb0>] __mutex_lock+0x70/0x374 > [<8073c2e0>] mutex_lock_nested+0x2c/0x38 > [<804b5414>] regmap_update_bits_base+0x38/0x8c > [<804ee584>] regmap_update_bits+0x1c/0x28 > [<804ee714>] ar9331_sw_unmask_irq+0x34/0x60 > [<800d91f0>] unmask_irq+0x48/0x70 > [<800d93d4>] irq_startup+0x114/0x11c > [<800d65b4>] __setup_irq+0x4f4/0x6d0 > [<800d68a0>] request_threaded_irq+0x110/0x190 > [<804e3ef0>] phy_request_interrupt+0x4c/0xe4 > [<804df508>] phylink_bringup_phy+0x2c0/0x37c > [<804df7bc>] phylink_of_phy_connect+0x118/0x130 > [<806c1a64>] dsa_slave_create+0x3d0/0x578 > [<806bc4ec>] dsa_register_switch+0x934/0xa20 > [<804eef98>] ar9331_sw_probe+0x34c/0x364 > [<804eb48c>] mdio_probe+0x44/0x70 > [<8049e3b4>] really_probe+0x30c/0x4f4 > [<8049ea10>] driver_probe_device+0x264/0x26c > [<8049bc10>] bus_for_each_drv+0xb4/0xd8 > [<8049e684>] __device_attach+0xe8/0x18c > [<8049ce58>] bus_probe_device+0x48/0xc4 > [<8049db70>] deferred_probe_work_func+0xdc/0xf8 > [<8009ff64>] process_one_work+0x2e4/0x4a0 > [<800a0770>] worker_thread+0x2a8/0x354 > [<800a774c>] kthread+0x16c/0x174 > [<8006306c>] ret_from_kernel_thread+0x14/0x1c > > [...] Here is the summary with links: - [v2] net: dsa: qca: ar9331: fix sleeping function called from invalid context bug https://git.kernel.org/netdev/net/c/3e47495fc4de You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/drivers/net/dsa/qca/ar9331.c b/drivers/net/dsa/qca/ar9331.c index e24a99031b80..4d49c5f2b790 100644 --- a/drivers/net/dsa/qca/ar9331.c +++ b/drivers/net/dsa/qca/ar9331.c @@ -159,6 +159,8 @@ struct ar9331_sw_priv { struct dsa_switch ds; struct dsa_switch_ops ops; struct irq_domain *irqdomain; + u32 irq_mask; + struct mutex lock_irq; struct mii_bus *mbus; /* mdio master */ struct mii_bus *sbus; /* mdio slave */ struct regmap *regmap; @@ -520,32 +522,44 @@ static irqreturn_t ar9331_sw_irq(int irq, void *data) static void ar9331_sw_mask_irq(struct irq_data *d) { struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); - struct regmap *regmap = priv->regmap; - int ret; - ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, - AR9331_SW_GINT_PHY_INT, 0); - if (ret) - dev_err(priv->dev, "could not mask IRQ\n"); + priv->irq_mask = 0; } static void ar9331_sw_unmask_irq(struct irq_data *d) +{ + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); + + priv->irq_mask = AR9331_SW_GINT_PHY_INT; +} + +static void ar9331_sw_irq_bus_lock(struct irq_data *d) +{ + struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); + + mutex_lock(&priv->lock_irq); +} + +static void ar9331_sw_irq_bus_sync_unlock(struct irq_data *d) { struct ar9331_sw_priv *priv = irq_data_get_irq_chip_data(d); struct regmap *regmap = priv->regmap; int ret; ret = regmap_update_bits(regmap, AR9331_SW_REG_GINT_MASK, - AR9331_SW_GINT_PHY_INT, - AR9331_SW_GINT_PHY_INT); + AR9331_SW_GINT_PHY_INT, priv->irq_mask); if (ret) - dev_err(priv->dev, "could not unmask IRQ\n"); + dev_err(priv->dev, "failed to change IRQ mask\n"); + + mutex_unlock(&priv->lock_irq); } static struct irq_chip ar9331_sw_irq_chip = { .name = AR9331_SW_NAME, .irq_mask = ar9331_sw_mask_irq, .irq_unmask = ar9331_sw_unmask_irq, + .irq_bus_lock = ar9331_sw_irq_bus_lock, + .irq_bus_sync_unlock = ar9331_sw_irq_bus_sync_unlock, }; static int ar9331_sw_irq_map(struct irq_domain *domain, unsigned int irq, @@ -584,6 +598,7 @@ static int ar9331_sw_irq_init(struct ar9331_sw_priv *priv) return irq ? irq : -EINVAL; } + mutex_init(&priv->lock_irq); ret = devm_request_threaded_irq(dev, irq, NULL, ar9331_sw_irq, IRQF_ONESHOT, AR9331_SW_NAME, priv); if (ret) {
With lockdep enabled, we will get following warning: ar9331_switch ethernet.1:10 lan0 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:00] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 18, name: kworker/0:1 INFO: lockdep is turned off. irq event stamp: 602 hardirqs last enabled at (601): [<8073fde0>] _raw_spin_unlock_irq+0x3c/0x80 hardirqs last disabled at (602): [<8073a4f4>] __schedule+0x184/0x800 softirqs last enabled at (0): [<80080f60>] copy_process+0x578/0x14c8 softirqs last disabled at (0): [<00000000>] 0x0 CPU: 0 PID: 18 Comm: kworker/0:1 Not tainted 5.10.0-rc3-ar9331-00734-g7d644991df0c #31 Workqueue: events deferred_probe_work_func Stack : 80980000 80980000 8089ef70 80890000 804b5414 80980000 00000002 80b53728 00000000 800d1268 804b5414 ffffffde 00000017 800afe08 81943860 0f5bfc32 00000000 00000000 8089ef70 819436c0 ffffffea 00000000 00000000 00000000 8194390c 808e353c 0000000f 66657272 80980000 00000000 00000000 80890000 804b5414 80980000 00000002 80b53728 00000000 00000000 00000000 80d40000 ... Call Trace: [<80069ce0>] show_stack+0x9c/0x140 [<800afe08>] ___might_sleep+0x220/0x244 [<8073bfb0>] __mutex_lock+0x70/0x374 [<8073c2e0>] mutex_lock_nested+0x2c/0x38 [<804b5414>] regmap_update_bits_base+0x38/0x8c [<804ee584>] regmap_update_bits+0x1c/0x28 [<804ee714>] ar9331_sw_unmask_irq+0x34/0x60 [<800d91f0>] unmask_irq+0x48/0x70 [<800d93d4>] irq_startup+0x114/0x11c [<800d65b4>] __setup_irq+0x4f4/0x6d0 [<800d68a0>] request_threaded_irq+0x110/0x190 [<804e3ef0>] phy_request_interrupt+0x4c/0xe4 [<804df508>] phylink_bringup_phy+0x2c0/0x37c [<804df7bc>] phylink_of_phy_connect+0x118/0x130 [<806c1a64>] dsa_slave_create+0x3d0/0x578 [<806bc4ec>] dsa_register_switch+0x934/0xa20 [<804eef98>] ar9331_sw_probe+0x34c/0x364 [<804eb48c>] mdio_probe+0x44/0x70 [<8049e3b4>] really_probe+0x30c/0x4f4 [<8049ea10>] driver_probe_device+0x264/0x26c [<8049bc10>] bus_for_each_drv+0xb4/0xd8 [<8049e684>] __device_attach+0xe8/0x18c [<8049ce58>] bus_probe_device+0x48/0xc4 [<8049db70>] deferred_probe_work_func+0xdc/0xf8 [<8009ff64>] process_one_work+0x2e4/0x4a0 [<800a0770>] worker_thread+0x2a8/0x354 [<800a774c>] kthread+0x16c/0x174 [<8006306c>] ret_from_kernel_thread+0x14/0x1c ar9331_switch ethernet.1:10 lan1 (uninitialized): PHY [!ahb!ethernet@1a000000!mdio!switch@10:02] driver [Qualcomm Atheros AR9331 built-in PHY] (irq=13) DSA: tree 0 setup To fix it, it is better to move access to MDIO register to the .irq_bus_sync_unlock call back. Fixes: ec6698c272de ("net: dsa: add support for Atheros AR9331 built-in switch") Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> --- changes v2: - fix comment on error drivers/net/dsa/qca/ar9331.c | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-)