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* [RESEND PATCH 0/5] kthread: remove worker->task self-assignment
@ 2026-08-29 16:11 Bradley Morgan
  2026-08-29 16:13 ` [PATCH 1/5] media: ivtv: convert to kthread_run_worker Bradley Morgan
                   ` (4 more replies)
  0 siblings, 5 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:11 UTC (permalink / raw)
  To: linux-kernel; +Cc: brads

From: Bradley Morgan <brads@mainlining.org>

Resent as a proper series with cover letter. The first send went out as
five separate threads instead of one.

kthread_worker_fn() has carried a FIXME for a decade: it assigns
worker->task = current because the old kthread_run(kthread_worker_fn)
callers never told the worker what task it was. The new
kthread_create_worker*() API sets worker->task before the worker even
starts, so the self-assignment is dead code.

Four drivers were still on the old API. Convert them, then remove the
FIXME.

No functional change intended.

Bradley Morgan (5):
  media: ivtv: convert to kthread_run_worker
  net: encx24j600: convert to kthread_run_worker
  tty: sc16is7xx: convert to kthread_run_worker
  cpufreq: schedutil: convert to kthread_create_worker
  kthread: remove worker->task self-assignment

 drivers/media/pci/ivtv/ivtv-driver.c    | 11 ++++-------
 drivers/media/pci/ivtv/ivtv-driver.h    |  3 +--
 drivers/net/ethernet/microchip/encx24j600.c | 12 ++++--------
 drivers/tty/serial/sc16is7xx.c        | 17 +++++++----------
 kernel/sched/cpufreq_schedutil.c       | 14 +++++--------
 kernel/kthread.c                      |  7 -------
 6 files changed, 21 insertions(+), 63 deletions(-)

^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH 1/5] media: ivtv: convert to kthread_run_worker
  2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
@ 2026-08-29 16:13 ` Bradley Morgan
  2026-08-29 16:15 ` [PATCH 2/5] net: encx24j600: " Bradley Morgan
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:13 UTC (permalink / raw)
  To: Andy Walls; +Cc: Mauro Carvalho Chehab, linux-media, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

Embedding a kthread_worker and running kthread_worker_fn yourself is
the old way. Convert ivtv to kthread_run_worker(), dropping the
separate irq_worker_task pointer.

This is part of removing the worker->task self-assignment in
kthread_worker_fn().

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 drivers/media/pci/ivtv/ivtv-driver.c | 14 ++++++--------
 drivers/media/pci/ivtv/ivtv-driver.h |  3 +--
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/media/pci/ivtv/ivtv-driver.c b/drivers/media/pci/ivtv/ivtv-driver.c
index b9ea56ec9593..6f0e0e46deb5 100644
--- a/drivers/media/pci/ivtv/ivtv-driver.c
+++ b/drivers/media/pci/ivtv/ivtv-driver.c
@@ -703,15 +703,13 @@ static int ivtv_init_struct1(struct ivtv *itv)
 	spin_lock_init(&itv->lock);
 	spin_lock_init(&itv->dma_reg_lock);
 
-	kthread_init_worker(&itv->irq_worker);
-	itv->irq_worker_task = kthread_run(kthread_worker_fn, &itv->irq_worker,
-					   "%s", itv->v4l2_dev.name);
-	if (IS_ERR(itv->irq_worker_task)) {
+	itv->irq_worker = kthread_run_worker(0, "%s", itv->v4l2_dev.name);
+	if (IS_ERR(itv->irq_worker)) {
 		IVTV_ERR("Could not create ivtv task\n");
 		return -1;
 	}
 	/* must use the FIFO scheduler as it is realtime sensitive */
-	sched_set_fifo(itv->irq_worker_task);
+	sched_set_fifo(itv->irq_worker->task);
 
 	kthread_init_work(&itv->irq_work, ivtv_irq_work_handler);
 
@@ -1232,7 +1230,7 @@ static int ivtv_probe(struct pci_dev *pdev, const struct pci_device_id *pci_id)
 	v4l2_ctrl_handler_free(&itv->cxhdl.hdl);
 	exit_ivtv_i2c(itv);
 free_worker:
-	kthread_stop(itv->irq_worker_task);
+	kthread_destroy_worker(itv->irq_worker);
 err:
 	if (retval == 0)
 		retval = -ENODEV;
@@ -1372,8 +1370,8 @@ static void ivtv_remove(struct pci_dev *pdev)
 	timer_shutdown_sync(&itv->dma_timer);
 
 	/* Kill irq worker */
-	kthread_flush_worker(&itv->irq_worker);
-	kthread_stop(itv->irq_worker_task);
+	kthread_flush_worker(itv->irq_worker);
+	kthread_destroy_worker(itv->irq_worker);
 
 	ivtv_streams_cleanup(itv);
 	ivtv_udma_free(itv);
diff --git a/drivers/media/pci/ivtv/ivtv-driver.h b/drivers/media/pci/ivtv/ivtv-driver.h
index 000e8beecc7c..091bc44f13bc 100644
--- a/drivers/media/pci/ivtv/ivtv-driver.h
+++ b/drivers/media/pci/ivtv/ivtv-driver.h
@@ -668,8 +668,7 @@ struct ivtv {
 	/* Interrupts & DMA */
 	u32 irqmask;                    /* active interrupts */
 	u32 irq_rr_idx;                 /* round-robin stream index */
-	struct kthread_worker irq_worker;		/* kthread worker for PIO/YUV/VBI actions */
-	struct task_struct *irq_worker_task;		/* task for irq_worker */
+	struct kthread_worker *irq_worker;		/* kthread worker for PIO/YUV/VBI actions */
 	struct kthread_work irq_work;	/* kthread work entry */
 	spinlock_t dma_reg_lock;        /* lock access to DMA engine registers */
 	int cur_dma_stream;		/* index of current stream doing DMA (-1 if none) */
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH 2/5] net: encx24j600: convert to kthread_run_worker
  2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
  2026-08-29 16:13 ` [PATCH 1/5] media: ivtv: convert to kthread_run_worker Bradley Morgan
@ 2026-08-29 16:15 ` Bradley Morgan
  2026-08-29 16:16 ` [PATCH 3/5] tty: sc16is7xx: " Bradley Morgan
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:15 UTC (permalink / raw)
  To: Andrew Lunn, David S . Miller
  Cc: Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

Embedding a kthread_worker and running kthread_worker_fn yourself is
the old way. Convert encx24j600 to kthread_run_worker(), dropping the
separate kworker_task pointer.

This is part of removing the worker->task self-assignment in
kthread_worker_fn().

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 drivers/net/ethernet/microchip/encx24j600.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/microchip/encx24j600.c b/drivers/net/ethernet/microchip/encx24j600.c
index b011bf5c2305..460189064332 100644
--- a/drivers/net/ethernet/microchip/encx24j600.c
+++ b/drivers/net/ethernet/microchip/encx24j600.c
@@ -49,8 +49,7 @@ struct encx24j600_priv {
 	struct mutex              lock; /* device access lock */
 	struct encx24j600_context ctx;
 	struct sk_buff           *tx_skb;
-	struct task_struct       *kworker_task;
-	struct kthread_worker     kworker;
+	struct kthread_worker    *kworker;
 	struct kthread_work       tx_work;
 	struct kthread_work       setrx_work;
 	u16                       next_packet;
@@ -823,7 +822,7 @@ static void encx24j600_set_multicast_list(struct net_device *dev)
 	}
 
 	if (oldfilter != priv->rxfilter)
-		kthread_queue_work(&priv->kworker, &priv->setrx_work);
+		kthread_queue_work(priv->kworker, &priv->setrx_work);
 }
 
 static void encx24j600_hw_tx(struct encx24j600_priv *priv)
@@ -884,7 +883,7 @@ static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
 	/* Remember the skb for deferred processing */
 	priv->tx_skb = skb;
 
-	kthread_queue_work(&priv->kworker, &priv->tx_work);
+	kthread_queue_work(priv->kworker, &priv->tx_work);
 
 	return NETDEV_TX_OK;
 }
@@ -1046,15 +1045,12 @@ static int encx24j600_spi_probe(struct spi_device *spi)
 	/* Initialize the device HW to the consistent state */
 	encx24j600_hw_init(priv);
 
-	kthread_init_worker(&priv->kworker);
 	kthread_init_work(&priv->tx_work, encx24j600_tx_proc);
 	kthread_init_work(&priv->setrx_work, encx24j600_setrx_proc);
 
-	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
-					 "encx24j600");
-
-	if (IS_ERR(priv->kworker_task)) {
-		ret = PTR_ERR(priv->kworker_task);
+	priv->kworker = kthread_run_worker(0, "encx24j600");
+	if (IS_ERR(priv->kworker)) {
+		ret = PTR_ERR(priv->kworker);
 		goto out_free;
 	}
 
@@ -1087,7 +1083,7 @@ static int encx24j600_spi_probe(struct spi_device *spi)
 out_unregister:
 	unregister_netdev(priv->ndev);
 out_stop:
-	kthread_stop(priv->kworker_task);
+	kthread_destroy_worker(priv->kworker);
 out_free:
 	free_netdev(ndev);
 
@@ -1100,7 +1096,7 @@ static void encx24j600_spi_remove(struct spi_device *spi)
 	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);
 
 	unregister_netdev(priv->ndev);
-	kthread_stop(priv->kworker_task);
+	kthread_destroy_worker(priv->kworker);
 
 	free_netdev(priv->ndev);
 }
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH 3/5] tty: sc16is7xx: convert to kthread_run_worker
  2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
  2026-08-29 16:13 ` [PATCH 1/5] media: ivtv: convert to kthread_run_worker Bradley Morgan
  2026-08-29 16:15 ` [PATCH 2/5] net: encx24j600: " Bradley Morgan
@ 2026-08-29 16:16 ` Bradley Morgan
  2026-08-29 16:17 ` [PATCH 4/5] cpufreq: schedutil: convert to kthread_create_worker Bradley Morgan
  2026-08-29 16:18 ` [PATCH] kthread: remove worker->task self-assignment Bradley Morgan
  4 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:16 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Jiri Slaby
  Cc: Hugo Villeneuve, linux-serial, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

Embedding a kthread_worker and running kthread_worker_fn yourself is
the old way. Convert sc16is7xx to kthread_run_worker(), dropping the
separate kworker_task pointer.

This is part of removing the worker->task self-assignment in
kthread_worker_fn().

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 drivers/tty/serial/sc16is7xx.c | 39 ++++++++++++++++------------------
 1 file changed, 18 insertions(+), 21 deletions(-)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 7107a0fb1e7b..2cfc1f290009 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -306,8 +306,7 @@ struct sc16is7xx_port {
 	unsigned long			gpio_valid_mask;
 #endif
 	u8				mctrl_mask;
-	struct kthread_worker		kworker;
-	struct task_struct		*kworker_task;
+	struct kthread_worker		*kworker;
 	struct kthread_delayed_work	poll_work;
 	bool				polling;
 	struct sc16is7xx_one		p[];
@@ -434,7 +433,7 @@ static void sc16is7xx_ier_clear(struct uart_port *port, u8 bit)
 	one->config.flags |= SC16IS7XX_RECONF_IER;
 	one->config.ier_mask |= bit;
 	one->config.ier_val &= ~bit;
-	kthread_queue_work(&s->kworker, &one->reg_work);
+	kthread_queue_work(s->kworker, &one->reg_work);
 }
 
 static void sc16is7xx_ier_set(struct uart_port *port, u8 bit)
@@ -447,7 +446,7 @@ static void sc16is7xx_ier_set(struct uart_port *port, u8 bit)
 	one->config.flags |= SC16IS7XX_RECONF_IER;
 	one->config.ier_mask |= bit;
 	one->config.ier_val |= bit;
-	kthread_queue_work(&s->kworker, &one->reg_work);
+	kthread_queue_work(s->kworker, &one->reg_work);
 }
 
 static void sc16is7xx_stop_tx(struct uart_port *port)
@@ -813,7 +812,7 @@ static void sc16is7xx_poll_proc(struct kthread_work *ws)
 	sc16is7xx_irq(0, s);
 
 	/* Setup delay based on SC16IS7XX_POLL_PERIOD_MS */
-	kthread_queue_delayed_work(&s->kworker, &s->poll_work,
+	kthread_queue_delayed_work(s->kworker, &s->poll_work,
 				   msecs_to_jiffies(SC16IS7XX_POLL_PERIOD_MS));
 }
 
@@ -900,7 +899,7 @@ static void sc16is7xx_ms_proc(struct kthread_work *ws)
 		scoped_guard(mutex, &one->lock)
 			sc16is7xx_update_mlines(one);
 
-		kthread_queue_delayed_work(&s->kworker, &one->ms_work, HZ);
+		kthread_queue_delayed_work(s->kworker, &one->ms_work, HZ);
 	}
 }
 
@@ -911,7 +910,7 @@ static void sc16is7xx_enable_ms(struct uart_port *port)
 
 	lockdep_assert_held_once(&port->lock);
 
-	kthread_queue_delayed_work(&s->kworker, &one->ms_work, 0);
+	kthread_queue_delayed_work(s->kworker, &one->ms_work, 0);
 }
 
 static void sc16is7xx_start_tx(struct uart_port *port)
@@ -919,7 +918,7 @@ static void sc16is7xx_start_tx(struct uart_port *port)
 	struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
 	struct sc16is7xx_one *one = to_sc16is7xx_one(port);
 
-	kthread_queue_work(&s->kworker, &one->tx_work);
+	kthread_queue_work(s->kworker, &one->tx_work);
 }
 
 static void sc16is7xx_throttle(struct uart_port *port)
@@ -968,7 +967,7 @@ static void sc16is7xx_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	struct sc16is7xx_one *one = to_sc16is7xx_one(port);
 
 	one->config.flags |= SC16IS7XX_RECONF_MD;
-	kthread_queue_work(&s->kworker, &one->reg_work);
+	kthread_queue_work(s->kworker, &one->reg_work);
 }
 
 static void sc16is7xx_break_ctl(struct uart_port *port, int break_state)
@@ -1098,7 +1097,7 @@ static int sc16is7xx_config_rs485(struct uart_port *port, struct ktermios *termi
 	}
 
 	one->config.flags |= SC16IS7XX_RECONF_RS485;
-	kthread_queue_work(&s->kworker, &one->reg_work);
+	kthread_queue_work(s->kworker, &one->reg_work);
 
 	return 0;
 }
@@ -1159,7 +1158,7 @@ static int sc16is7xx_startup(struct uart_port *port)
 	uart_port_unlock_irqrestore(port, flags);
 
 	if (s->polling)
-		kthread_queue_delayed_work(&s->kworker, &s->poll_work,
+		kthread_queue_delayed_work(s->kworker, &s->poll_work,
 					   msecs_to_jiffies(SC16IS7XX_POLL_PERIOD_MS));
 
 	return 0;
@@ -1186,7 +1185,7 @@ static void sc16is7xx_shutdown(struct uart_port *port)
 	if (s->polling)
 		kthread_cancel_delayed_work_sync(&s->poll_work);
 
-	kthread_flush_worker(&s->kworker);
+	kthread_flush_worker(s->kworker);
 }
 
 static const char *sc16is7xx_type(struct uart_port *port)
@@ -1595,14 +1594,12 @@ int sc16is7xx_probe(struct device *dev, const struct sc16is7xx_devtype *devtype,
 	s->devtype = devtype;
 	dev_set_drvdata(dev, s);
 
-	kthread_init_worker(&s->kworker);
-	s->kworker_task = kthread_run(kthread_worker_fn, &s->kworker,
-				      "sc16is7xx");
-	if (IS_ERR(s->kworker_task)) {
-		ret = PTR_ERR(s->kworker_task);
+	s->kworker = kthread_run_worker(0, "sc16is7xx");
+	if (IS_ERR(s->kworker)) {
+		ret = PTR_ERR(s->kworker);
 		goto out_clk;
 	}
-	sched_set_fifo(s->kworker_task);
+	sched_set_fifo(s->kworker->task);
 
 	ret = sc16is7xx_reset(dev, regmaps[0]);
 	if (ret)
@@ -1676,7 +1673,7 @@ int sc16is7xx_probe(struct device *dev, const struct sc16is7xx_devtype *devtype,
 	}
 
 out_kthread:
-	kthread_stop(s->kworker_task);
+	kthread_destroy_worker(s->kworker);
 
 out_clk:
 	clk_disable_unprepare(s->clk);
@@ -1705,8 +1702,8 @@ void sc16is7xx_remove(struct device *dev)
 	if (s->polling)
 		kthread_cancel_delayed_work_sync(&s->poll_work);
 
-	kthread_flush_worker(&s->kworker);
-	kthread_stop(s->kworker_task);
+	kthread_flush_worker(s->kworker);
+	kthread_destroy_worker(s->kworker);
 
 	clk_disable_unprepare(s->clk);
 }
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH 4/5] cpufreq: schedutil: convert to kthread_create_worker
  2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
                   ` (2 preceding siblings ...)
  2026-08-29 16:16 ` [PATCH 3/5] tty: sc16is7xx: " Bradley Morgan
@ 2026-08-29 16:17 ` Bradley Morgan
  2026-08-29 16:18 ` [PATCH] kthread: remove worker->task self-assignment Bradley Morgan
  4 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:17 UTC (permalink / raw)
  To: Rafael J . Wysocki, Viresh Kumar
  Cc: Ingo Molnar, Peter Zijlstra, linux-pm, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

Embedding a kthread_worker and running kthread_worker_fn yourself is
the old way. Convert cpufreq_schedutil to kthread_create_worker(),
dropping the separate thread pointer.

This is part of removing the worker->task self-assignment in
kthread_worker_fn().

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 kernel/sched/cpufreq_schedutil.c | 33 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 19 deletions(-)

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 49ccd6f1c185..5023c24d8a21 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -31,8 +31,7 @@ struct sugov_policy {
 	struct			irq_work irq_work;
 	struct			kthread_work work;
 	struct			mutex work_lock;
-	struct			kthread_worker worker;
-	struct task_struct	*thread;
+	struct			kthread_worker *worker;
 	bool			work_in_progress;
 
 	bool			limits_changed;
@@ -586,7 +585,7 @@ static void sugov_irq_work(struct irq_work *irq_work)
 
 	sg_policy = container_of(irq_work, struct sugov_policy, irq_work);
 
-	kthread_queue_work(&sg_policy->worker, &sg_policy->work);
+	kthread_queue_work(sg_policy->worker, &sg_policy->work);
 }
 
 /************************** sysfs interface ************************/
@@ -669,7 +668,6 @@ static void sugov_policy_free(struct sugov_policy *sg_policy)
 
 static int sugov_kthread_create(struct sugov_policy *sg_policy)
 {
-	struct task_struct *thread;
 	struct sched_attr attr = {
 		.size		= sizeof(struct sched_attr),
 		.sched_policy	= SCHED_DEADLINE,
@@ -692,32 +690,29 @@ static int sugov_kthread_create(struct sugov_policy *sg_policy)
 		return 0;
 
 	kthread_init_work(&sg_policy->work, sugov_work);
-	kthread_init_worker(&sg_policy->worker);
-	thread = kthread_create(kthread_worker_fn, &sg_policy->worker,
-				"sugov:%d",
-				cpumask_first(policy->related_cpus));
-	if (IS_ERR(thread)) {
-		pr_err("failed to create sugov thread: %pe\n", thread);
-		return PTR_ERR(thread);
+	sg_policy->worker = kthread_create_worker(0, "sugov:%d",
+						cpumask_first(policy->related_cpus));
+	if (IS_ERR(sg_policy->worker)) {
+		pr_err("failed to create sugov thread: %pe\n", sg_policy->worker);
+		return PTR_ERR(sg_policy->worker);
 	}
 
-	ret = sched_setattr_nocheck(thread, &attr);
+	ret = sched_setattr_nocheck(sg_policy->worker->task, &attr);
 	if (ret) {
-		kthread_stop(thread);
+		kthread_destroy_worker(sg_policy->worker);
 		pr_warn("%s: failed to set SCHED_DEADLINE\n", __func__);
 		return ret;
 	}
 
-	sg_policy->thread = thread;
 	if (policy->dvfs_possible_from_any_cpu)
-		set_cpus_allowed_ptr(thread, policy->related_cpus);
+		set_cpus_allowed_ptr(sg_policy->worker->task, policy->related_cpus);
 	else
-		kthread_bind_mask(thread, policy->related_cpus);
+		kthread_bind_mask(sg_policy->worker->task, policy->related_cpus);
 
 	init_irq_work(&sg_policy->irq_work, sugov_irq_work);
 	mutex_init(&sg_policy->work_lock);
 
-	wake_up_process(thread);
+	wake_up_process(sg_policy->worker->task);
 
 	return 0;
 }
@@ -728,8 +723,8 @@ static void sugov_kthread_stop(struct sugov_policy *sg_policy)
 	if (sg_policy->policy->fast_switch_enabled)
 		return;
 
-	kthread_flush_worker(&sg_policy->worker);
-	kthread_stop(sg_policy->thread);
+	kthread_flush_worker(sg_policy->worker);
+	kthread_destroy_worker(sg_policy->worker);
 	mutex_destroy(&sg_policy->work_lock);
 }
 
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH] kthread: remove worker->task self-assignment
  2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
                   ` (3 preceding siblings ...)
  2026-08-29 16:17 ` [PATCH 4/5] cpufreq: schedutil: convert to kthread_create_worker Bradley Morgan
@ 2026-08-29 16:18 ` Bradley Morgan
  2026-09-01 12:45   ` Frederic Weisbecker
  4 siblings, 1 reply; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:18 UTC (permalink / raw)
  To: Frederic Weisbecker, Tejun Heo; +Cc: Peter Zijlstra, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

All kthread worker users now create their workers with
kthread_create_worker*(), which sets worker->task before the worker
starts. The self-assignment in kthread_worker_fn() is dead code now.

Remove it.

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 kernel/kthread.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 63beb59b7a3d..18bc702e8d2d 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
 	struct kthread_worker *worker = worker_ptr;
 	struct kthread_work *work;
 
-	/*
-	 * FIXME: Update the check and remove the assignment when all kthread
-	 * worker users are created using kthread_create_worker*() functions.
-	 */
-	WARN_ON(worker->task && worker->task != current);
-	worker->task = current;
-
 	if (worker->flags & KTW_FREEZABLE)
 		set_freezable();
 
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-08-29 16:18 ` [PATCH] kthread: remove worker->task self-assignment Bradley Morgan
@ 2026-09-01 12:45   ` Frederic Weisbecker
  2026-09-01 12:49     ` Peter Zijlstra
  0 siblings, 1 reply; 17+ messages in thread
From: Frederic Weisbecker @ 2026-09-01 12:45 UTC (permalink / raw)
  To: Bradley Morgan; +Cc: Tejun Heo, Peter Zijlstra, linux-kernel, brads

Hi,

Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
> From: Bradley Morgan <brads@mainlining.org>
> 
> All kthread worker users now create their workers with
> kthread_create_worker*(), which sets worker->task before the worker
> starts. The self-assignment in kthread_worker_fn() is dead code now.

How could it be created before?

> 
> Remove it.
> 
> Signed-off-by: Bradley Morgan <brads@mainlining.org>
> ---
>  kernel/kthread.c | 7 -------
>  1 file changed, 7 deletions(-)
> 
> diff --git a/kernel/kthread.c b/kernel/kthread.c
> index 63beb59b7a3d..18bc702e8d2d 100644
> --- a/kernel/kthread.c
> +++ b/kernel/kthread.c
> @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>  	struct kthread_worker *worker = worker_ptr;
>  	struct kthread_work *work;
>  
> -	/*
> -	 * FIXME: Update the check and remove the assignment when all kthread
> -	 * worker users are created using kthread_create_worker*() functions.
> -	 */
> -	WARN_ON(worker->task && worker->task != current);

Should we keep a WARN_ON(worker->task != current) here?

Thanks.

> -	worker->task = current;
> -
>  	if (worker->flags & KTW_FREEZABLE)
>  		set_freezable();
>  
> -- 
> 2.47.3

-- 
Frederic Weisbecker
SUSE Labs

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 12:45   ` Frederic Weisbecker
@ 2026-09-01 12:49     ` Peter Zijlstra
  2026-09-01 13:57       ` Bradley Morgan
  0 siblings, 1 reply; 17+ messages in thread
From: Peter Zijlstra @ 2026-09-01 12:49 UTC (permalink / raw)
  To: Frederic Weisbecker; +Cc: Bradley Morgan, Tejun Heo, linux-kernel, brads

On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
> Hi,
> 
> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
> > From: Bradley Morgan <brads@mainlining.org>
> > 
> > All kthread worker users now create their workers with
> > kthread_create_worker*(), which sets worker->task before the worker
> > starts. The self-assignment in kthread_worker_fn() is dead code now.
> 
> How could it be created before?
> 
> > 
> > Remove it.
> > 
> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
> > ---
> >  kernel/kthread.c | 7 -------
> >  1 file changed, 7 deletions(-)
> > 
> > diff --git a/kernel/kthread.c b/kernel/kthread.c
> > index 63beb59b7a3d..18bc702e8d2d 100644
> > --- a/kernel/kthread.c
> > +++ b/kernel/kthread.c
> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
> >  	struct kthread_worker *worker = worker_ptr;
> >  	struct kthread_work *work;
> >  
> > -	/*
> > -	 * FIXME: Update the check and remove the assignment when all kthread
> > -	 * worker users are created using kthread_create_worker*() functions.
> > -	 */
> > -	WARN_ON(worker->task && worker->task != current);
> 
> Should we keep a WARN_ON(worker->task != current) here?

I vote yes! Paranoia is good :-)

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 12:49     ` Peter Zijlstra
@ 2026-09-01 13:57       ` Bradley Morgan
  2026-09-01 14:04         ` Bradley Morgan
  2026-09-01 14:06         ` Frederic Weisbecker
  0 siblings, 2 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-09-01 13:57 UTC (permalink / raw)
  To: Peter Zijlstra, Frederic Weisbecker
  Cc: Bradley Morgan, Tejun Heo, linux-kernel

On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
wrote:
>On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>> Hi,
>> 
>> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>> > From: Bradley Morgan <brads@mainlining.org>
>> > 
>> > All kthread worker users now create their workers with
>> > kthread_create_worker*(), which sets worker->task before the worker
>> > starts. The self-assignment in kthread_worker_fn() is dead code now.
>> 
>> How could it be created before?
>> 
>> > 
>> > Remove it.
>> > 
>> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>> > ---
>> >  kernel/kthread.c | 7 -------
>> >  1 file changed, 7 deletions(-)
>> > 
>> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>> > index 63beb59b7a3d..18bc702e8d2d 100644
>> > --- a/kernel/kthread.c
>> > +++ b/kernel/kthread.c
>> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>> >  	struct kthread_worker *worker = worker_ptr;
>> >  	struct kthread_work *work;
>> >  
>> > -	/*
>> > -	 * FIXME: Update the check and remove the assignment when all kthread
>> > -	 * worker users are created using kthread_create_worker*() functions.
>> > -	 */
>> > -	WARN_ON(worker->task && worker->task != current);
>> 
>> Should we keep a WARN_ON(worker->task != current) here?
>
>I vote yes! Paranoia is good :-)
>


Yeah, but it *should* be useless. Do you really want me to readd the warn
statement? Maybe add some text, like

"worker->task is deprecated"?

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 13:57       ` Bradley Morgan
@ 2026-09-01 14:04         ` Bradley Morgan
  2026-09-01 14:06         ` Frederic Weisbecker
  1 sibling, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-09-01 14:04 UTC (permalink / raw)
  To: Peter Zijlstra, Frederic Weisbecker
  Cc: Bradley Morgan, Tejun Heo, linux-kernel

On 1 September 2026 14:57:38 BST, Bradley Morgan <brads@mainlining.org>
wrote:
>On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
>wrote:
>>On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>>> Hi,
>>> 
>>> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>>> > From: Bradley Morgan <brads@mainlining.org>
>>> > 
>>> > All kthread worker users now create their workers with
>>> > kthread_create_worker*(), which sets worker->task before the worker
>>> > starts. The self-assignment in kthread_worker_fn() is dead code now.
>>> 
>>> How could it be created before?
>>> 
>>> > 
>>> > Remove it.
>>> > 
>>> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>>> > ---
>>> >  kernel/kthread.c | 7 -------
>>> >  1 file changed, 7 deletions(-)
>>> > 
>>> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>>> > index 63beb59b7a3d..18bc702e8d2d 100644
>>> > --- a/kernel/kthread.c
>>> > +++ b/kernel/kthread.c
>>> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>>> >  	struct kthread_worker *worker = worker_ptr;
>>> >  	struct kthread_work *work;
>>> >  
>>> > -	/*
>>> > -	 * FIXME: Update the check and remove the assignment when all kthread
>>> > -	 * worker users are created using kthread_create_worker*() functions.
>>> > -	 */
>>> > -	WARN_ON(worker->task && worker->task != current);
>>> 
>>> Should we keep a WARN_ON(worker->task != current) here?
>>
>>I vote yes! Paranoia is good :-)
>>
>
>
>Yeah, but it *should* be useless. Do you really want me to readd the warn
>statement? Maybe add some text, like
>
>"worker->task is deprecated"?

Btw this is a "something around the lines of", so it's definitely not
gonna be this! (Its sorta wrong too)

>
>--- Thanks!
>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 13:57       ` Bradley Morgan
  2026-09-01 14:04         ` Bradley Morgan
@ 2026-09-01 14:06         ` Frederic Weisbecker
  2026-09-01 14:09           ` Bradley Morgan
  2026-09-01 18:28           ` Bradley Morgan
  1 sibling, 2 replies; 17+ messages in thread
From: Frederic Weisbecker @ 2026-09-01 14:06 UTC (permalink / raw)
  To: Bradley Morgan; +Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
> wrote:
> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
> >> Hi,
> >> 
> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
> >> > From: Bradley Morgan <brads@mainlining.org>
> >> > 
> >> > All kthread worker users now create their workers with
> >> > kthread_create_worker*(), which sets worker->task before the worker
> >> > starts. The self-assignment in kthread_worker_fn() is dead code now.
> >> 
> >> How could it be created before?
> >> 
> >> > 
> >> > Remove it.
> >> > 
> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
> >> > ---
> >> >  kernel/kthread.c | 7 -------
> >> >  1 file changed, 7 deletions(-)
> >> > 
> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
> >> > index 63beb59b7a3d..18bc702e8d2d 100644
> >> > --- a/kernel/kthread.c
> >> > +++ b/kernel/kthread.c
> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
> >> >  	struct kthread_worker *worker = worker_ptr;
> >> >  	struct kthread_work *work;
> >> >  
> >> > -	/*
> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
> >> > -	 * worker users are created using kthread_create_worker*() functions.
> >> > -	 */
> >> > -	WARN_ON(worker->task && worker->task != current);
> >> 
> >> Should we keep a WARN_ON(worker->task != current) here?
> >
> >I vote yes! Paranoia is good :-)
> >
> 
> 
> Yeah, but it *should* be useless.

Famous last words :-)

> Do you really want me to readd the warn
> statement? Maybe add some text, like
> 
> "worker->task is deprecated"?

Is it deprecated? We still need that field for wakeup on queue at least.
Don't bother with a message, it's only a sanity check.

Thanks.

> 
> --- Thanks!
> https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

-- 
Frederic Weisbecker
SUSE Labs

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 14:06         ` Frederic Weisbecker
@ 2026-09-01 14:09           ` Bradley Morgan
  2026-09-02 14:09             ` Frederic Weisbecker
  2026-09-01 18:28           ` Bradley Morgan
  1 sibling, 1 reply; 17+ messages in thread
From: Bradley Morgan @ 2026-09-01 14:09 UTC (permalink / raw)
  To: Frederic Weisbecker
  Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

On 1 September 2026 15:06:51 BST, Frederic Weisbecker <frederic@kernel.org>
wrote:
>Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
>> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
>> wrote:
>> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>> >> Hi,
>> >> 
>> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>> >> > From: Bradley Morgan <brads@mainlining.org>
>> >> > 
>> >> > All kthread worker users now create their workers with
>> >> > kthread_create_worker*(), which sets worker->task before the worker
>> >> > starts. The self-assignment in kthread_worker_fn() is dead code
>now.
>> >> 
>> >> How could it be created before?
>> >> 
>> >> > 
>> >> > Remove it.
>> >> > 
>> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>> >> > ---
>> >> >  kernel/kthread.c | 7 -------
>> >> >  1 file changed, 7 deletions(-)
>> >> > 
>> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>> >> > index 63beb59b7a3d..18bc702e8d2d 100644
>> >> > --- a/kernel/kthread.c
>> >> > +++ b/kernel/kthread.c
>> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>> >> >  	struct kthread_worker *worker = worker_ptr;
>> >> >  	struct kthread_work *work;
>> >> >  
>> >> > -	/*
>> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
>> >> > -	 * worker users are created using kthread_create_worker*() functions.
>> >> > -	 */
>> >> > -	WARN_ON(worker->task && worker->task != current);
>> >> 
>> >> Should we keep a WARN_ON(worker->task != current) here?
>> >
>> >I vote yes! Paranoia is good :-)
>> >
>> 
>> 
>> Yeah, but it *should* be useless.
>
>Famous last words :-)
>

Hahahaha

>> Do you really want me to readd the warn
>> statement? Maybe add some text, like
>> 
>> "worker->task is deprecated"?
>
>Is it deprecated? We still need that field for wakeup on queue at least.
>Don't bother with a message, it's only a sanity check.

Okie, I did convert all the drivers as you can see, if you wanna give it a
lookie

>
>Thanks.
>
>> 
>> --- Thanks!
>>
>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
>
>

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 14:06         ` Frederic Weisbecker
  2026-09-01 14:09           ` Bradley Morgan
@ 2026-09-01 18:28           ` Bradley Morgan
  2026-09-02 14:10             ` Frederic Weisbecker
  1 sibling, 1 reply; 17+ messages in thread
From: Bradley Morgan @ 2026-09-01 18:28 UTC (permalink / raw)
  To: Frederic Weisbecker
  Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

On 1 September 2026 15:06:51 BST, Frederic Weisbecker <frederic@kernel.org>
wrote:
>Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
>> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
>> wrote:
>> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>> >> Hi,
>> >> 
>> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>> >> > From: Bradley Morgan <brads@mainlining.org>
>> >> > 
>> >> > All kthread worker users now create their workers with
>> >> > kthread_create_worker*(), which sets worker->task before the worker
>> >> > starts. The self-assignment in kthread_worker_fn() is dead code
>now.
>> >> 
>> >> How could it be created before?
>> >> 
>> >> > 
>> >> > Remove it.
>> >> > 
>> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>> >> > ---
>> >> >  kernel/kthread.c | 7 -------
>> >> >  1 file changed, 7 deletions(-)
>> >> > 
>> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>> >> > index 63beb59b7a3d..18bc702e8d2d 100644
>> >> > --- a/kernel/kthread.c
>> >> > +++ b/kernel/kthread.c
>> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>> >> >  	struct kthread_worker *worker = worker_ptr;
>> >> >  	struct kthread_work *work;
>> >> >  
>> >> > -	/*
>> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
>> >> > -	 * worker users are created using kthread_create_worker*() functions.
>> >> > -	 */
>> >> > -	WARN_ON(worker->task && worker->task != current);
>> >> 
>> >> Should we keep a WARN_ON(worker->task != current) here?
>> >
>> >I vote yes! Paranoia is good :-)
>> >
>> 
>> 
>> Yeah, but it *should* be useless.
>
>Famous last words :-)
>
>> Do you really want me to readd the warn
>> statement? Maybe add some text, like
>> 
>> "worker->task is deprecated"?
>
>Is it deprecated? We still need that field for wakeup on queue at least.
>Don't bother with a message, it's only a sanity check.
>
>Thanks.

Hi, I hopped on the computer, 

Right, so the whole warn on things is good, but I converted all the
callers, so it'll never fire.

For OOT users, maybe this'll be beneficial (but yk what their like, theyll
remove the warn on)

Guys, what do you think?

>
>> 
>> --- Thanks!
>>
>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
>
>

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 14:09           ` Bradley Morgan
@ 2026-09-02 14:09             ` Frederic Weisbecker
  2026-09-02 14:11               ` Bradley Morgan
  0 siblings, 1 reply; 17+ messages in thread
From: Frederic Weisbecker @ 2026-09-02 14:09 UTC (permalink / raw)
  To: Bradley Morgan; +Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

Le Tue, Sep 01, 2026 at 03:09:03PM +0100, Bradley Morgan a écrit :
> On 1 September 2026 15:06:51 BST, Frederic Weisbecker <frederic@kernel.org>
> wrote:
> >Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
> >> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
> >> wrote:
> >> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
> >> >> Hi,
> >> >> 
> >> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
> >> >> > From: Bradley Morgan <brads@mainlining.org>
> >> >> > 
> >> >> > All kthread worker users now create their workers with
> >> >> > kthread_create_worker*(), which sets worker->task before the worker
> >> >> > starts. The self-assignment in kthread_worker_fn() is dead code
> >now.
> >> >> 
> >> >> How could it be created before?
> >> >> 
> >> >> > 
> >> >> > Remove it.
> >> >> > 
> >> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
> >> >> > ---
> >> >> >  kernel/kthread.c | 7 -------
> >> >> >  1 file changed, 7 deletions(-)
> >> >> > 
> >> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
> >> >> > index 63beb59b7a3d..18bc702e8d2d 100644
> >> >> > --- a/kernel/kthread.c
> >> >> > +++ b/kernel/kthread.c
> >> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
> >> >> >  	struct kthread_worker *worker = worker_ptr;
> >> >> >  	struct kthread_work *work;
> >> >> >  
> >> >> > -	/*
> >> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
> >> >> > -	 * worker users are created using kthread_create_worker*() functions.
> >> >> > -	 */
> >> >> > -	WARN_ON(worker->task && worker->task != current);
> >> >> 
> >> >> Should we keep a WARN_ON(worker->task != current) here?
> >> >
> >> >I vote yes! Paranoia is good :-)
> >> >
> >> 
> >> 
> >> Yeah, but it *should* be useless.
> >
> >Famous last words :-)
> >
> 
> Hahahaha
> 
> >> Do you really want me to readd the warn
> >> statement? Maybe add some text, like
> >> 
> >> "worker->task is deprecated"?
> >
> >Is it deprecated? We still need that field for wakeup on queue at least.
> >Don't bother with a message, it's only a sanity check.
> 
> Okie, I did convert all the drivers as you can see, if you wanna give it a
> lookie

Do you have a link to that?

Thanks.

> 
> >
> >Thanks.
> >
> >> 
> >> --- Thanks!
> >>
> >https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
> >
> >
> 
> --- Thanks!
> https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

-- 
Frederic Weisbecker
SUSE Labs

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-01 18:28           ` Bradley Morgan
@ 2026-09-02 14:10             ` Frederic Weisbecker
  0 siblings, 0 replies; 17+ messages in thread
From: Frederic Weisbecker @ 2026-09-02 14:10 UTC (permalink / raw)
  To: Bradley Morgan; +Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

Le Tue, Sep 01, 2026 at 07:28:19PM +0100, Bradley Morgan a écrit :
> On 1 September 2026 15:06:51 BST, Frederic Weisbecker <frederic@kernel.org>
> wrote:
> >Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
> >> On 1 September 2026 13:49:00 BST, Peter Zijlstra <peterz@infradead.org>
> >> wrote:
> >> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
> >> >> Hi,
> >> >> 
> >> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
> >> >> > From: Bradley Morgan <brads@mainlining.org>
> >> >> > 
> >> >> > All kthread worker users now create their workers with
> >> >> > kthread_create_worker*(), which sets worker->task before the worker
> >> >> > starts. The self-assignment in kthread_worker_fn() is dead code
> >now.
> >> >> 
> >> >> How could it be created before?
> >> >> 
> >> >> > 
> >> >> > Remove it.
> >> >> > 
> >> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
> >> >> > ---
> >> >> >  kernel/kthread.c | 7 -------
> >> >> >  1 file changed, 7 deletions(-)
> >> >> > 
> >> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
> >> >> > index 63beb59b7a3d..18bc702e8d2d 100644
> >> >> > --- a/kernel/kthread.c
> >> >> > +++ b/kernel/kthread.c
> >> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
> >> >> >  	struct kthread_worker *worker = worker_ptr;
> >> >> >  	struct kthread_work *work;
> >> >> >  
> >> >> > -	/*
> >> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
> >> >> > -	 * worker users are created using kthread_create_worker*() functions.
> >> >> > -	 */
> >> >> > -	WARN_ON(worker->task && worker->task != current);
> >> >> 
> >> >> Should we keep a WARN_ON(worker->task != current) here?
> >> >
> >> >I vote yes! Paranoia is good :-)
> >> >
> >> 
> >> 
> >> Yeah, but it *should* be useless.
> >
> >Famous last words :-)
> >
> >> Do you really want me to readd the warn
> >> statement? Maybe add some text, like
> >> 
> >> "worker->task is deprecated"?
> >
> >Is it deprecated? We still need that field for wakeup on queue at least.
> >Don't bother with a message, it's only a sanity check.
> >
> >Thanks.
> 
> Hi, I hopped on the computer, 
> 
> Right, so the whole warn on things is good, but I converted all the
> callers, so it'll never fire.
> 
> For OOT users, maybe this'll be beneficial (but yk what their like, theyll
> remove the warn on)
> 
> Guys, what do you think?

The warning is mostly to prevent from future changes to break.

Thanks.

> 
> >
> >> 
> >> --- Thanks!
> >>
> >https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
> >
> >
> 
> --- Thanks!
> https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

-- 
Frederic Weisbecker
SUSE Labs

^ permalink raw reply	[flat|nested] 17+ messages in thread

* Re: [PATCH] kthread: remove worker->task self-assignment
  2026-09-02 14:09             ` Frederic Weisbecker
@ 2026-09-02 14:11               ` Bradley Morgan
  0 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-09-02 14:11 UTC (permalink / raw)
  To: Frederic Weisbecker
  Cc: Peter Zijlstra, Bradley Morgan, Tejun Heo, linux-kernel

On 2 September 2026 15:09:05 BST, Frederic Weisbecker <frederic@kernel.org>
wrote:
>Le Tue, Sep 01, 2026 at 03:09:03PM +0100, Bradley Morgan a écrit :
>> On 1 September 2026 15:06:51 BST, Frederic Weisbecker
><frederic@kernel.org>
>> wrote:
>> >Le Tue, Sep 01, 2026 at 02:57:38PM +0100, Bradley Morgan a écrit :
>> >> On 1 September 2026 13:49:00 BST, Peter Zijlstra
><peterz@infradead.org>
>> >> wrote:
>> >> >On Tue, Sep 01, 2026 at 02:45:43PM +0200, Frederic Weisbecker wrote:
>> >> >> Hi,
>> >> >> 
>> >> >> Le Sat, Aug 29, 2026 at 04:18:48PM +0000, Bradley Morgan a écrit :
>> >> >> > From: Bradley Morgan <brads@mainlining.org>
>> >> >> > 
>> >> >> > All kthread worker users now create their workers with
>> >> >> > kthread_create_worker*(), which sets worker->task before the
>worker
>> >> >> > starts. The self-assignment in kthread_worker_fn() is dead code
>> >now.
>> >> >> 
>> >> >> How could it be created before?
>> >> >> 
>> >> >> > 
>> >> >> > Remove it.
>> >> >> > 
>> >> >> > Signed-off-by: Bradley Morgan <brads@mainlining.org>
>> >> >> > ---
>> >> >> >  kernel/kthread.c | 7 -------
>> >> >> >  1 file changed, 7 deletions(-)
>> >> >> > 
>> >> >> > diff --git a/kernel/kthread.c b/kernel/kthread.c
>> >> >> > index 63beb59b7a3d..18bc702e8d2d 100644
>> >> >> > --- a/kernel/kthread.c
>> >> >> > +++ b/kernel/kthread.c
>> >> >> > @@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
>> >> >> >  	struct kthread_worker *worker = worker_ptr;
>> >> >> >  	struct kthread_work *work;
>> >> >> >  
>> >> >> > -	/*
>> >> >> > -	 * FIXME: Update the check and remove the assignment when all kthread
>> >> >> > -	 * worker users are created using kthread_create_worker*() functions.
>> >> >> > -	 */
>> >> >> > -	WARN_ON(worker->task && worker->task != current);
>> >> >> 
>> >> >> Should we keep a WARN_ON(worker->task != current) here?
>> >> >
>> >> >I vote yes! Paranoia is good :-)
>> >> >
>> >> 
>> >> 
>> >> Yeah, but it *should* be useless.
>> >
>> >Famous last words :-)
>> >
>> 
>> Hahahaha
>> 
>> >> Do you really want me to readd the warn
>> >> statement? Maybe add some text, like
>> >> 
>> >> "worker->task is deprecated"?
>> >
>> >Is it deprecated? We still need that field for wakeup on queue at
>least.
>> >Don't bother with a message, it's only a sanity check.
>> 
>> Okie, I did convert all the drivers as you can see, if you wanna give it
>a
>> lookie
>
>Do you have a link to that?
>
>Thanks.

uhh, they should be all in-reply-tos, so if you search for my series in
lore, this patch replies to all of the conversions




>
>> 
>> >
>> >Thanks.
>> >
>> >> 
>> >> --- Thanks!
>> >>
>>
>>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
>> >
>> >
>> 
>> --- Thanks!
>>
>https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/
>
>

--- Thanks!
https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@grrlz.net/

^ permalink raw reply	[flat|nested] 17+ messages in thread

* [PATCH] kthread: remove worker->task self-assignment
@ 2026-08-29 16:01 Bradley Morgan
  0 siblings, 0 replies; 17+ messages in thread
From: Bradley Morgan @ 2026-08-29 16:01 UTC (permalink / raw)
  To: Frederic Weisbecker, Tejun Heo; +Cc: Peter Zijlstra, linux-kernel, brads

From: Bradley Morgan <brads@mainlining.org>

All kthread worker users now create their workers with
kthread_create_worker*(), which sets worker->task before the worker
starts. The self-assignment in kthread_worker_fn() is dead code now.

Remove it.

Signed-off-by: Bradley Morgan <brads@mainlining.org>
---
 kernel/kthread.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 63beb59b7a3d..18bc702e8d2d 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -987,13 +987,6 @@ int kthread_worker_fn(void *worker_ptr)
 	struct kthread_worker *worker = worker_ptr;
 	struct kthread_work *work;
 
-	/*
-	 * FIXME: Update the check and remove the assignment when all kthread
-	 * worker users are created using kthread_create_worker*() functions.
-	 */
-	WARN_ON(worker->task && worker->task != current);
-	worker->task = current;
-
 	if (worker->flags & KTW_FREEZABLE)
 		set_freezable();
 
-- 
2.47.3


^ permalink raw reply	[flat|nested] 17+ messages in thread

end of thread, other threads:[~2026-09-02 14:12 UTC | newest]

Thread overview: 17+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2026-08-29 16:11 [RESEND PATCH 0/5] kthread: remove worker->task self-assignment Bradley Morgan
2026-08-29 16:13 ` [PATCH 1/5] media: ivtv: convert to kthread_run_worker Bradley Morgan
2026-08-29 16:15 ` [PATCH 2/5] net: encx24j600: " Bradley Morgan
2026-08-29 16:16 ` [PATCH 3/5] tty: sc16is7xx: " Bradley Morgan
2026-08-29 16:17 ` [PATCH 4/5] cpufreq: schedutil: convert to kthread_create_worker Bradley Morgan
2026-08-29 16:18 ` [PATCH] kthread: remove worker->task self-assignment Bradley Morgan
2026-09-01 12:45   ` Frederic Weisbecker
2026-09-01 12:49     ` Peter Zijlstra
2026-09-01 13:57       ` Bradley Morgan
2026-09-01 14:04         ` Bradley Morgan
2026-09-01 14:06         ` Frederic Weisbecker
2026-09-01 14:09           ` Bradley Morgan
2026-09-02 14:09             ` Frederic Weisbecker
2026-09-02 14:11               ` Bradley Morgan
2026-09-01 18:28           ` Bradley Morgan
2026-09-02 14:10             ` Frederic Weisbecker
  -- strict thread matches above, loose matches on Subject: below --
2026-08-29 16:01 Bradley Morgan

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