The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 58d7668242647e661a20efe065519abd6454287e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050604-spookily-ethics-ea27@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 58d7668242647e661a20efe065519abd6454287e Mon Sep 17 00:00:00 2001
From: "Joel Fernandes (Google)" <joel(a)joelfernandes.org>
Date: Tue, 24 Jan 2023 17:31:26 +0000
Subject: [PATCH] tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz
subsystem
For CONFIG_NO_HZ_FULL systems, the tick_do_timer_cpu cannot be offlined.
However, cpu_is_hotpluggable() still returns true for those CPUs. This causes
torture tests that do offlining to end up trying to offline this CPU causing
test failures. Such failure happens on all architectures.
Fix the repeated error messages thrown by this (even if the hotplug errors are
harmless) by asking the opinion of the nohz subsystem on whether the CPU can be
hotplugged.
[ Apply Frederic Weisbecker feedback on refactoring tick_nohz_cpu_down(). ]
For drivers/base/ portion:
Acked-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Acked-by: Frederic Weisbecker <frederic(a)kernel.org>
Cc: Frederic Weisbecker <frederic(a)kernel.org>
Cc: "Paul E. McKenney" <paulmck(a)kernel.org>
Cc: Zhouyi Zhou <zhouzhouyi(a)gmail.com>
Cc: Will Deacon <will(a)kernel.org>
Cc: Marc Zyngier <maz(a)kernel.org>
Cc: rcu <rcu(a)vger.kernel.org>
Cc: stable(a)vger.kernel.org
Fixes: 2987557f52b9 ("driver-core/cpu: Expose hotpluggability to the rest of the kernel")
Signed-off-by: Paul E. McKenney <paulmck(a)kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel(a)joelfernandes.org>
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 182c6122f815..c1815b9dae68 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -487,7 +487,8 @@ static const struct attribute_group *cpu_root_attr_groups[] = {
bool cpu_is_hotpluggable(unsigned int cpu)
{
struct device *dev = get_cpu_device(cpu);
- return dev && container_of(dev, struct cpu, dev)->hotpluggable;
+ return dev && container_of(dev, struct cpu, dev)->hotpluggable
+ && tick_nohz_cpu_hotpluggable(cpu);
}
EXPORT_SYMBOL_GPL(cpu_is_hotpluggable);
diff --git a/include/linux/tick.h b/include/linux/tick.h
index bfd571f18cfd..9459fef5b857 100644
--- a/include/linux/tick.h
+++ b/include/linux/tick.h
@@ -216,6 +216,7 @@ extern void tick_nohz_dep_set_signal(struct task_struct *tsk,
enum tick_dep_bits bit);
extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
enum tick_dep_bits bit);
+extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
/*
* The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
@@ -280,6 +281,7 @@ static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
+static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
static inline void tick_dep_set(enum tick_dep_bits bit) { }
static inline void tick_dep_clear(enum tick_dep_bits bit) { }
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index b0e3c9205946..68d81a4283c8 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -527,7 +527,7 @@ void __init tick_nohz_full_setup(cpumask_var_t cpumask)
tick_nohz_full_running = true;
}
-static int tick_nohz_cpu_down(unsigned int cpu)
+bool tick_nohz_cpu_hotpluggable(unsigned int cpu)
{
/*
* The tick_do_timer_cpu CPU handles housekeeping duty (unbound
@@ -535,8 +535,13 @@ static int tick_nohz_cpu_down(unsigned int cpu)
* CPUs. It must remain online when nohz full is enabled.
*/
if (tick_nohz_full_running && tick_do_timer_cpu == cpu)
- return -EBUSY;
- return 0;
+ return false;
+ return true;
+}
+
+static int tick_nohz_cpu_down(unsigned int cpu)
+{
+ return tick_nohz_cpu_hotpluggable(cpu) ? 0 : -EBUSY;
}
void __init tick_nohz_init(void)
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 146a37e05d620cef4ad430e5d1c9c077fe6fa76f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050630-epilogue-durably-bd7f@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 146a37e05d620cef4ad430e5d1c9c077fe6fa76f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:18 +0200
Subject: [PATCH] serial: 8250: Fix serial8250_tx_empty() race with DMA Tx
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
There's a potential race before THRE/TEMT deasserts when DMA Tx is
starting up (or the next batch of continuous Tx is being submitted).
This can lead to misdetecting Tx empty condition.
It is entirely normal for THRE/TEMT to be set for some time after the
DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely
not empty at that point, it seems incorrect for serial8250_tx_empty()
claim Tx is empty.
Fix the race by also checking in serial8250_tx_empty() whether there's
DMA Tx active.
Note: This fix only addresses in-kernel race mainly to make using
TCSADRAIN/FLUSH robust. Userspace can still cause other races but they
seem userspace concurrency control problems.
Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 287153d32536..1e8fe44a7099 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -365,6 +365,13 @@ static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p)
if (dma->prepare_rx_dma)
dma->prepare_rx_dma(p);
}
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ struct uart_8250_dma *dma = p->dma;
+
+ return dma && dma->tx_running;
+}
#else
static inline int serial8250_tx_dma(struct uart_8250_port *p)
{
@@ -380,6 +387,11 @@ static inline int serial8250_request_dma(struct uart_8250_port *p)
return -1;
}
static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ return false;
+}
#endif
static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index fa43df05342b..107bcdfb119c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2005,18 +2005,19 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
static unsigned int serial8250_tx_empty(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int result = 0;
unsigned long flags;
- u16 lsr;
serial8250_rpm_get(up);
spin_lock_irqsave(&port->lock, flags);
- lsr = serial_lsr_in(up);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ result = TIOCSER_TEMT;
spin_unlock_irqrestore(&port->lock, flags);
serial8250_rpm_put(up);
- return uart_lsr_tx_empty(lsr) ? TIOCSER_TEMT : 0;
+ return result;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 146a37e05d620cef4ad430e5d1c9c077fe6fa76f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050629-nastily-commodity-a7ad@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 146a37e05d620cef4ad430e5d1c9c077fe6fa76f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:18 +0200
Subject: [PATCH] serial: 8250: Fix serial8250_tx_empty() race with DMA Tx
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
There's a potential race before THRE/TEMT deasserts when DMA Tx is
starting up (or the next batch of continuous Tx is being submitted).
This can lead to misdetecting Tx empty condition.
It is entirely normal for THRE/TEMT to be set for some time after the
DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely
not empty at that point, it seems incorrect for serial8250_tx_empty()
claim Tx is empty.
Fix the race by also checking in serial8250_tx_empty() whether there's
DMA Tx active.
Note: This fix only addresses in-kernel race mainly to make using
TCSADRAIN/FLUSH robust. Userspace can still cause other races but they
seem userspace concurrency control problems.
Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 287153d32536..1e8fe44a7099 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -365,6 +365,13 @@ static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p)
if (dma->prepare_rx_dma)
dma->prepare_rx_dma(p);
}
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ struct uart_8250_dma *dma = p->dma;
+
+ return dma && dma->tx_running;
+}
#else
static inline int serial8250_tx_dma(struct uart_8250_port *p)
{
@@ -380,6 +387,11 @@ static inline int serial8250_request_dma(struct uart_8250_port *p)
return -1;
}
static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ return false;
+}
#endif
static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index fa43df05342b..107bcdfb119c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2005,18 +2005,19 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
static unsigned int serial8250_tx_empty(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int result = 0;
unsigned long flags;
- u16 lsr;
serial8250_rpm_get(up);
spin_lock_irqsave(&port->lock, flags);
- lsr = serial_lsr_in(up);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ result = TIOCSER_TEMT;
spin_unlock_irqrestore(&port->lock, flags);
serial8250_rpm_put(up);
- return uart_lsr_tx_empty(lsr) ? TIOCSER_TEMT : 0;
+ return result;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 146a37e05d620cef4ad430e5d1c9c077fe6fa76f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050628-gonad-hatchback-b646@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 146a37e05d620cef4ad430e5d1c9c077fe6fa76f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:18 +0200
Subject: [PATCH] serial: 8250: Fix serial8250_tx_empty() race with DMA Tx
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
There's a potential race before THRE/TEMT deasserts when DMA Tx is
starting up (or the next batch of continuous Tx is being submitted).
This can lead to misdetecting Tx empty condition.
It is entirely normal for THRE/TEMT to be set for some time after the
DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely
not empty at that point, it seems incorrect for serial8250_tx_empty()
claim Tx is empty.
Fix the race by also checking in serial8250_tx_empty() whether there's
DMA Tx active.
Note: This fix only addresses in-kernel race mainly to make using
TCSADRAIN/FLUSH robust. Userspace can still cause other races but they
seem userspace concurrency control problems.
Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 287153d32536..1e8fe44a7099 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -365,6 +365,13 @@ static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p)
if (dma->prepare_rx_dma)
dma->prepare_rx_dma(p);
}
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ struct uart_8250_dma *dma = p->dma;
+
+ return dma && dma->tx_running;
+}
#else
static inline int serial8250_tx_dma(struct uart_8250_port *p)
{
@@ -380,6 +387,11 @@ static inline int serial8250_request_dma(struct uart_8250_port *p)
return -1;
}
static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ return false;
+}
#endif
static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index fa43df05342b..107bcdfb119c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2005,18 +2005,19 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
static unsigned int serial8250_tx_empty(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int result = 0;
unsigned long flags;
- u16 lsr;
serial8250_rpm_get(up);
spin_lock_irqsave(&port->lock, flags);
- lsr = serial_lsr_in(up);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ result = TIOCSER_TEMT;
spin_unlock_irqrestore(&port->lock, flags);
serial8250_rpm_put(up);
- return uart_lsr_tx_empty(lsr) ? TIOCSER_TEMT : 0;
+ return result;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 146a37e05d620cef4ad430e5d1c9c077fe6fa76f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050628-groggy-thicket-3d84@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 146a37e05d620cef4ad430e5d1c9c077fe6fa76f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:18 +0200
Subject: [PATCH] serial: 8250: Fix serial8250_tx_empty() race with DMA Tx
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
There's a potential race before THRE/TEMT deasserts when DMA Tx is
starting up (or the next batch of continuous Tx is being submitted).
This can lead to misdetecting Tx empty condition.
It is entirely normal for THRE/TEMT to be set for some time after the
DMA Tx had been setup in serial8250_tx_dma(). As Tx side is definitely
not empty at that point, it seems incorrect for serial8250_tx_empty()
claim Tx is empty.
Fix the race by also checking in serial8250_tx_empty() whether there's
DMA Tx active.
Note: This fix only addresses in-kernel race mainly to make using
TCSADRAIN/FLUSH robust. Userspace can still cause other races but they
seem userspace concurrency control problems.
Fixes: 9ee4b83e51f74 ("serial: 8250: Add support for dmaengine")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-3-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 287153d32536..1e8fe44a7099 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -365,6 +365,13 @@ static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p)
if (dma->prepare_rx_dma)
dma->prepare_rx_dma(p);
}
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ struct uart_8250_dma *dma = p->dma;
+
+ return dma && dma->tx_running;
+}
#else
static inline int serial8250_tx_dma(struct uart_8250_port *p)
{
@@ -380,6 +387,11 @@ static inline int serial8250_request_dma(struct uart_8250_port *p)
return -1;
}
static inline void serial8250_release_dma(struct uart_8250_port *p) { }
+
+static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
+{
+ return false;
+}
#endif
static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index fa43df05342b..107bcdfb119c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2005,18 +2005,19 @@ static int serial8250_tx_threshold_handle_irq(struct uart_port *port)
static unsigned int serial8250_tx_empty(struct uart_port *port)
{
struct uart_8250_port *up = up_to_u8250p(port);
+ unsigned int result = 0;
unsigned long flags;
- u16 lsr;
serial8250_rpm_get(up);
spin_lock_irqsave(&port->lock, flags);
- lsr = serial_lsr_in(up);
+ if (!serial8250_tx_dma_running(up) && uart_lsr_tx_empty(serial_lsr_in(up)))
+ result = TIOCSER_TEMT;
spin_unlock_irqrestore(&port->lock, flags);
serial8250_rpm_put(up);
- return uart_lsr_tx_empty(lsr) ? TIOCSER_TEMT : 0;
+ return result;
}
unsigned int serial8250_do_get_mctrl(struct uart_port *port)
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y
git checkout FETCH_HEAD
git cherry-pick -x 094fb49a2d0d6827c86d2e0840873e6db0c491d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050619-enticing-deliverer-8a62@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 094fb49a2d0d6827c86d2e0840873e6db0c491d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:17 +0200
Subject: [PATCH] tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSH
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If userspace races tcsetattr() with a write, the drained condition
might not be guaranteed by the kernel. There is a race window after
checking Tx is empty before tty_set_termios() takes termios_rwsem for
write. During that race window, more characters can be queued by a
racing writer.
Any ongoing transmission might produce garbage during HW's
->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be
preventing such a character corruption. If those flags are set, take
tty's write lock to stop any writer before performing the lower layer
Tx empty check and wait for the pending characters to be sent (if any).
The initial wait for all-writers-done must be placed outside of tty's
write lock to avoid deadlock which makes it impossible to use
tty_wait_until_sent(). The write lock is retried if a racing write is
detected.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h
index f45cd683c02e..1e0d80e98d26 100644
--- a/drivers/tty/tty.h
+++ b/drivers/tty/tty.h
@@ -62,6 +62,8 @@ int __tty_check_change(struct tty_struct *tty, int sig);
int tty_check_change(struct tty_struct *tty);
void __stop_tty(struct tty_struct *tty);
void __start_tty(struct tty_struct *tty);
+void tty_write_unlock(struct tty_struct *tty);
+int tty_write_lock(struct tty_struct *tty, int ndelay);
void tty_vhangup_session(struct tty_struct *tty);
void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 766750e355ac..cfb3da0dee47 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -933,13 +933,13 @@ static ssize_t tty_read(struct kiocb *iocb, struct iov_iter *to)
return i;
}
-static void tty_write_unlock(struct tty_struct *tty)
+void tty_write_unlock(struct tty_struct *tty)
{
mutex_unlock(&tty->atomic_write_lock);
wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT);
}
-static int tty_write_lock(struct tty_struct *tty, int ndelay)
+int tty_write_lock(struct tty_struct *tty, int ndelay)
{
if (!mutex_trylock(&tty->atomic_write_lock)) {
if (ndelay)
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 32ff9959b565..2e88b414cf95 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -501,21 +501,42 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
- ld = tty_ldisc_ref(tty);
+ if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) {
+retry_write_wait:
+ retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty));
+ if (retval < 0)
+ return retval;
- if (ld != NULL) {
- if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
- ld->ops->flush_buffer(tty);
- tty_ldisc_deref(ld);
- }
+ if (tty_write_lock(tty, 0) < 0)
+ goto retry_write_wait;
- if (opt & TERMIOS_WAIT) {
- tty_wait_until_sent(tty, 0);
- if (signal_pending(current))
- return -ERESTARTSYS;
- }
+ /* Racing writer? */
+ if (tty_chars_in_buffer(tty)) {
+ tty_write_unlock(tty);
+ goto retry_write_wait;
+ }
- tty_set_termios(tty, &tmp_termios);
+ ld = tty_ldisc_ref(tty);
+ if (ld != NULL) {
+ if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
+ tty_ldisc_deref(ld);
+ }
+
+ if ((opt & TERMIOS_WAIT) && tty->ops->wait_until_sent) {
+ tty->ops->wait_until_sent(tty, 0);
+ if (signal_pending(current)) {
+ tty_write_unlock(tty);
+ return -ERESTARTSYS;
+ }
+ }
+
+ tty_set_termios(tty, &tmp_termios);
+
+ tty_write_unlock(tty);
+ } else {
+ tty_set_termios(tty, &tmp_termios);
+ }
/* FIXME: Arguably if tmp_termios == tty->termios AND the
actual requested termios was not tmp_termios then we may
The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y
git checkout FETCH_HEAD
git cherry-pick -x 094fb49a2d0d6827c86d2e0840873e6db0c491d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050618-vowel-angular-3166@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 094fb49a2d0d6827c86d2e0840873e6db0c491d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:17 +0200
Subject: [PATCH] tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSH
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If userspace races tcsetattr() with a write, the drained condition
might not be guaranteed by the kernel. There is a race window after
checking Tx is empty before tty_set_termios() takes termios_rwsem for
write. During that race window, more characters can be queued by a
racing writer.
Any ongoing transmission might produce garbage during HW's
->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be
preventing such a character corruption. If those flags are set, take
tty's write lock to stop any writer before performing the lower layer
Tx empty check and wait for the pending characters to be sent (if any).
The initial wait for all-writers-done must be placed outside of tty's
write lock to avoid deadlock which makes it impossible to use
tty_wait_until_sent(). The write lock is retried if a racing write is
detected.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h
index f45cd683c02e..1e0d80e98d26 100644
--- a/drivers/tty/tty.h
+++ b/drivers/tty/tty.h
@@ -62,6 +62,8 @@ int __tty_check_change(struct tty_struct *tty, int sig);
int tty_check_change(struct tty_struct *tty);
void __stop_tty(struct tty_struct *tty);
void __start_tty(struct tty_struct *tty);
+void tty_write_unlock(struct tty_struct *tty);
+int tty_write_lock(struct tty_struct *tty, int ndelay);
void tty_vhangup_session(struct tty_struct *tty);
void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 766750e355ac..cfb3da0dee47 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -933,13 +933,13 @@ static ssize_t tty_read(struct kiocb *iocb, struct iov_iter *to)
return i;
}
-static void tty_write_unlock(struct tty_struct *tty)
+void tty_write_unlock(struct tty_struct *tty)
{
mutex_unlock(&tty->atomic_write_lock);
wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT);
}
-static int tty_write_lock(struct tty_struct *tty, int ndelay)
+int tty_write_lock(struct tty_struct *tty, int ndelay)
{
if (!mutex_trylock(&tty->atomic_write_lock)) {
if (ndelay)
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 32ff9959b565..2e88b414cf95 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -501,21 +501,42 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
- ld = tty_ldisc_ref(tty);
+ if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) {
+retry_write_wait:
+ retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty));
+ if (retval < 0)
+ return retval;
- if (ld != NULL) {
- if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
- ld->ops->flush_buffer(tty);
- tty_ldisc_deref(ld);
- }
+ if (tty_write_lock(tty, 0) < 0)
+ goto retry_write_wait;
- if (opt & TERMIOS_WAIT) {
- tty_wait_until_sent(tty, 0);
- if (signal_pending(current))
- return -ERESTARTSYS;
- }
+ /* Racing writer? */
+ if (tty_chars_in_buffer(tty)) {
+ tty_write_unlock(tty);
+ goto retry_write_wait;
+ }
- tty_set_termios(tty, &tmp_termios);
+ ld = tty_ldisc_ref(tty);
+ if (ld != NULL) {
+ if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
+ tty_ldisc_deref(ld);
+ }
+
+ if ((opt & TERMIOS_WAIT) && tty->ops->wait_until_sent) {
+ tty->ops->wait_until_sent(tty, 0);
+ if (signal_pending(current)) {
+ tty_write_unlock(tty);
+ return -ERESTARTSYS;
+ }
+ }
+
+ tty_set_termios(tty, &tmp_termios);
+
+ tty_write_unlock(tty);
+ } else {
+ tty_set_termios(tty, &tmp_termios);
+ }
/* FIXME: Arguably if tmp_termios == tty->termios AND the
actual requested termios was not tmp_termios then we may
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 094fb49a2d0d6827c86d2e0840873e6db0c491d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050617-diaphragm-citric-aee0@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 094fb49a2d0d6827c86d2e0840873e6db0c491d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:17 +0200
Subject: [PATCH] tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSH
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If userspace races tcsetattr() with a write, the drained condition
might not be guaranteed by the kernel. There is a race window after
checking Tx is empty before tty_set_termios() takes termios_rwsem for
write. During that race window, more characters can be queued by a
racing writer.
Any ongoing transmission might produce garbage during HW's
->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be
preventing such a character corruption. If those flags are set, take
tty's write lock to stop any writer before performing the lower layer
Tx empty check and wait for the pending characters to be sent (if any).
The initial wait for all-writers-done must be placed outside of tty's
write lock to avoid deadlock which makes it impossible to use
tty_wait_until_sent(). The write lock is retried if a racing write is
detected.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h
index f45cd683c02e..1e0d80e98d26 100644
--- a/drivers/tty/tty.h
+++ b/drivers/tty/tty.h
@@ -62,6 +62,8 @@ int __tty_check_change(struct tty_struct *tty, int sig);
int tty_check_change(struct tty_struct *tty);
void __stop_tty(struct tty_struct *tty);
void __start_tty(struct tty_struct *tty);
+void tty_write_unlock(struct tty_struct *tty);
+int tty_write_lock(struct tty_struct *tty, int ndelay);
void tty_vhangup_session(struct tty_struct *tty);
void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 766750e355ac..cfb3da0dee47 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -933,13 +933,13 @@ static ssize_t tty_read(struct kiocb *iocb, struct iov_iter *to)
return i;
}
-static void tty_write_unlock(struct tty_struct *tty)
+void tty_write_unlock(struct tty_struct *tty)
{
mutex_unlock(&tty->atomic_write_lock);
wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT);
}
-static int tty_write_lock(struct tty_struct *tty, int ndelay)
+int tty_write_lock(struct tty_struct *tty, int ndelay)
{
if (!mutex_trylock(&tty->atomic_write_lock)) {
if (ndelay)
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 32ff9959b565..2e88b414cf95 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -501,21 +501,42 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
- ld = tty_ldisc_ref(tty);
+ if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) {
+retry_write_wait:
+ retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty));
+ if (retval < 0)
+ return retval;
- if (ld != NULL) {
- if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
- ld->ops->flush_buffer(tty);
- tty_ldisc_deref(ld);
- }
+ if (tty_write_lock(tty, 0) < 0)
+ goto retry_write_wait;
- if (opt & TERMIOS_WAIT) {
- tty_wait_until_sent(tty, 0);
- if (signal_pending(current))
- return -ERESTARTSYS;
- }
+ /* Racing writer? */
+ if (tty_chars_in_buffer(tty)) {
+ tty_write_unlock(tty);
+ goto retry_write_wait;
+ }
- tty_set_termios(tty, &tmp_termios);
+ ld = tty_ldisc_ref(tty);
+ if (ld != NULL) {
+ if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
+ tty_ldisc_deref(ld);
+ }
+
+ if ((opt & TERMIOS_WAIT) && tty->ops->wait_until_sent) {
+ tty->ops->wait_until_sent(tty, 0);
+ if (signal_pending(current)) {
+ tty_write_unlock(tty);
+ return -ERESTARTSYS;
+ }
+ }
+
+ tty_set_termios(tty, &tmp_termios);
+
+ tty_write_unlock(tty);
+ } else {
+ tty_set_termios(tty, &tmp_termios);
+ }
/* FIXME: Arguably if tmp_termios == tty->termios AND the
actual requested termios was not tmp_termios then we may
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 094fb49a2d0d6827c86d2e0840873e6db0c491d2
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023050616-mop-student-e9b0@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 094fb49a2d0d6827c86d2e0840873e6db0c491d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen(a)linux.intel.com>
Date: Fri, 17 Mar 2023 13:33:17 +0200
Subject: [PATCH] tty: Prevent writing chars during tcsetattr TCSADRAIN/FLUSH
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
If userspace races tcsetattr() with a write, the drained condition
might not be guaranteed by the kernel. There is a race window after
checking Tx is empty before tty_set_termios() takes termios_rwsem for
write. During that race window, more characters can be queued by a
racing writer.
Any ongoing transmission might produce garbage during HW's
->set_termios() call. The intent of TCSADRAIN/FLUSH seems to be
preventing such a character corruption. If those flags are set, take
tty's write lock to stop any writer before performing the lower layer
Tx empty check and wait for the pending characters to be sent (if any).
The initial wait for all-writers-done must be placed outside of tty's
write lock to avoid deadlock which makes it impossible to use
tty_wait_until_sent(). The write lock is retried if a racing write is
detected.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable(a)vger.kernel.org
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen(a)linux.intel.com>
Link: https://lore.kernel.org/r/20230317113318.31327-2-ilpo.jarvinen@linux.intel.…
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h
index f45cd683c02e..1e0d80e98d26 100644
--- a/drivers/tty/tty.h
+++ b/drivers/tty/tty.h
@@ -62,6 +62,8 @@ int __tty_check_change(struct tty_struct *tty, int sig);
int tty_check_change(struct tty_struct *tty);
void __stop_tty(struct tty_struct *tty);
void __start_tty(struct tty_struct *tty);
+void tty_write_unlock(struct tty_struct *tty);
+int tty_write_lock(struct tty_struct *tty, int ndelay);
void tty_vhangup_session(struct tty_struct *tty);
void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 766750e355ac..cfb3da0dee47 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -933,13 +933,13 @@ static ssize_t tty_read(struct kiocb *iocb, struct iov_iter *to)
return i;
}
-static void tty_write_unlock(struct tty_struct *tty)
+void tty_write_unlock(struct tty_struct *tty)
{
mutex_unlock(&tty->atomic_write_lock);
wake_up_interruptible_poll(&tty->write_wait, EPOLLOUT);
}
-static int tty_write_lock(struct tty_struct *tty, int ndelay)
+int tty_write_lock(struct tty_struct *tty, int ndelay)
{
if (!mutex_trylock(&tty->atomic_write_lock)) {
if (ndelay)
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 32ff9959b565..2e88b414cf95 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -501,21 +501,42 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
- ld = tty_ldisc_ref(tty);
+ if (opt & (TERMIOS_FLUSH|TERMIOS_WAIT)) {
+retry_write_wait:
+ retval = wait_event_interruptible(tty->write_wait, !tty_chars_in_buffer(tty));
+ if (retval < 0)
+ return retval;
- if (ld != NULL) {
- if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
- ld->ops->flush_buffer(tty);
- tty_ldisc_deref(ld);
- }
+ if (tty_write_lock(tty, 0) < 0)
+ goto retry_write_wait;
- if (opt & TERMIOS_WAIT) {
- tty_wait_until_sent(tty, 0);
- if (signal_pending(current))
- return -ERESTARTSYS;
- }
+ /* Racing writer? */
+ if (tty_chars_in_buffer(tty)) {
+ tty_write_unlock(tty);
+ goto retry_write_wait;
+ }
- tty_set_termios(tty, &tmp_termios);
+ ld = tty_ldisc_ref(tty);
+ if (ld != NULL) {
+ if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+ ld->ops->flush_buffer(tty);
+ tty_ldisc_deref(ld);
+ }
+
+ if ((opt & TERMIOS_WAIT) && tty->ops->wait_until_sent) {
+ tty->ops->wait_until_sent(tty, 0);
+ if (signal_pending(current)) {
+ tty_write_unlock(tty);
+ return -ERESTARTSYS;
+ }
+ }
+
+ tty_set_termios(tty, &tmp_termios);
+
+ tty_write_unlock(tty);
+ } else {
+ tty_set_termios(tty, &tmp_termios);
+ }
/* FIXME: Arguably if tmp_termios == tty->termios AND the
actual requested termios was not tmp_termios then we may
Hello,
recently I've debugged a deadlock issue in ext4 fast commit feature in our
openSUSE Leap kernel. Checking with upstream I've found out the issue was
accidentally fixed by commit 2729cfdcfa1c ("ext4: use
ext4_journal_start/stop for fast commit transactions"). Can you please pick
up this commit into the stable tree? The problem has been there since fast
commit began to exist (in 5.10-rc1) so 5.10 and 5.15 stable trees need the
fix. Thanks!
Honza
--
Jan Kara <jack(a)suse.com>
SUSE Labs, CR