* Patch "Input: i8042 - break load dependency between atkbd/psmouse and i8042" has been added to the 4.7-stable tree
@ 2016-09-05 14:29 gregkh
0 siblings, 0 replies; 2+ messages in thread
From: gregkh @ 2016-09-05 14:29 UTC (permalink / raw)
To: dmitry.torokhov, gregkh, mdl; +Cc: stable, stable-commits
This is a note to let you know that I've just added the patch titled
Input: i8042 - break load dependency between atkbd/psmouse and i8042
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
input-i8042-break-load-dependency-between-atkbd-psmouse-and-i8042.patch
and it can be found in the queue-4.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
>From 4097461897df91041382ff6fcd2bfa7ee6b2448c Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Mon, 25 Jul 2016 11:36:54 -0700
Subject: Input: i8042 - break load dependency between atkbd/psmouse and i8042
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
commit 4097461897df91041382ff6fcd2bfa7ee6b2448c upstream.
As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.
> hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
> driver like atkbd.c. atkbd.c depends on libps2.c because it invokes
> ps2_command(). libps2.c depends on i8042.c because it invokes
> i8042_check_port_owner(). As a result, hyperv_keyboard actually
> depends on i8042.c.
>
> For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
> Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
> rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
> no i8042 device emulated) and finally hyperv_keyboard can't work and
> the user can't input: https://bugs.archlinux.org/task/39820
> (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)
To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.
Reported-by: Mark Laws <mdl@60hz.org>
Tested-by: Mark Laws <mdl@60hz.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/input/serio/i8042.c | 16 +---------------
drivers/input/serio/libps2.c | 10 ++++------
include/linux/i8042.h | 6 ------
include/linux/serio.h | 24 +++++++++++++++++++-----
4 files changed, 24 insertions(+), 32 deletions(-)
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -1277,6 +1277,7 @@ static int __init i8042_create_kbd_port(
serio->start = i8042_start;
serio->stop = i8042_stop;
serio->close = i8042_port_close;
+ serio->ps2_cmd_mutex = &i8042_mutex;
serio->port_data = port;
serio->dev.parent = &i8042_platform_device->dev;
strlcpy(serio->name, "i8042 KBD port", sizeof(serio->name));
@@ -1373,21 +1374,6 @@ static void i8042_unregister_ports(void)
}
}
-/*
- * Checks whether port belongs to i8042 controller.
- */
-bool i8042_check_port_owner(const struct serio *port)
-{
- int i;
-
- for (i = 0; i < I8042_NUM_PORTS; i++)
- if (i8042_ports[i].serio == port)
- return true;
-
- return false;
-}
-EXPORT_SYMBOL(i8042_check_port_owner);
-
static void i8042_free_irqs(void)
{
if (i8042_aux_irq_registered)
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -56,19 +56,17 @@ EXPORT_SYMBOL(ps2_sendbyte);
void ps2_begin_command(struct ps2dev *ps2dev)
{
- mutex_lock(&ps2dev->cmd_mutex);
+ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
- if (i8042_check_port_owner(ps2dev->serio))
- i8042_lock_chip();
+ mutex_lock(m);
}
EXPORT_SYMBOL(ps2_begin_command);
void ps2_end_command(struct ps2dev *ps2dev)
{
- if (i8042_check_port_owner(ps2dev->serio))
- i8042_unlock_chip();
+ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
- mutex_unlock(&ps2dev->cmd_mutex);
+ mutex_unlock(m);
}
EXPORT_SYMBOL(ps2_end_command);
--- a/include/linux/i8042.h
+++ b/include/linux/i8042.h
@@ -62,7 +62,6 @@ struct serio;
void i8042_lock_chip(void);
void i8042_unlock_chip(void);
int i8042_command(unsigned char *param, int command);
-bool i8042_check_port_owner(const struct serio *);
int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio));
int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
@@ -83,11 +82,6 @@ static inline int i8042_command(unsigned
return -ENODEV;
}
-static inline bool i8042_check_port_owner(const struct serio *serio)
-{
- return false;
-}
-
static inline int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio))
{
--- a/include/linux/serio.h
+++ b/include/linux/serio.h
@@ -31,7 +31,8 @@ struct serio {
struct serio_device_id id;
- spinlock_t lock; /* protects critical sections from port's interrupt handler */
+ /* Protects critical sections from port's interrupt handler */
+ spinlock_t lock;
int (*write)(struct serio *, unsigned char);
int (*open)(struct serio *);
@@ -40,16 +41,29 @@ struct serio {
void (*stop)(struct serio *);
struct serio *parent;
- struct list_head child_node; /* Entry in parent->children list */
+ /* Entry in parent->children list */
+ struct list_head child_node;
struct list_head children;
- unsigned int depth; /* level of nesting in serio hierarchy */
+ /* Level of nesting in serio hierarchy */
+ unsigned int depth;
- struct serio_driver *drv; /* accessed from interrupt, must be protected by serio->lock and serio->sem */
- struct mutex drv_mutex; /* protects serio->drv so attributes can pin driver */
+ /*
+ * serio->drv is accessed from interrupt handlers; when modifying
+ * caller should acquire serio->drv_mutex and serio->lock.
+ */
+ struct serio_driver *drv;
+ /* Protects serio->drv so attributes can pin current driver */
+ struct mutex drv_mutex;
struct device dev;
struct list_head node;
+
+ /*
+ * For use by PS/2 layer when several ports share hardware and
+ * may get indigestion when exposed to concurrent access (i8042).
+ */
+ struct mutex *ps2_cmd_mutex;
};
#define to_serio_port(d) container_of(d, struct serio, dev)
Patches currently in stable-queue which might be from dmitry.torokhov@gmail.com are
queue-4.7/input-i8042-set-up-shared-ps2_cmd_mutex-for-aux-ports.patch
queue-4.7/input-tegra-kbc-fix-inverted-reset-logic.patch
queue-4.7/pinctrl-meson-drop-pinctrl_unregister-for-devm_-registered-device.patch
queue-4.7/input-synaptics-rmi4-fix-register-descriptor-subpacket-map-construction.patch
queue-4.7/input-i8042-break-load-dependency-between-atkbd-psmouse-and-i8042.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
* Patch "Input: i8042 - break load dependency between atkbd/psmouse and i8042" has been added to the 4.7-stable tree
@ 2016-08-18 13:14 gregkh
0 siblings, 0 replies; 2+ messages in thread
From: gregkh @ 2016-08-18 13:14 UTC (permalink / raw)
To: dmitry.torokhov, gregkh, mdl; +Cc: stable, stable-commits
This is a note to let you know that I've just added the patch titled
Input: i8042 - break load dependency between atkbd/psmouse and i8042
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
input-i8042-break-load-dependency-between-atkbd-psmouse-and-i8042.patch
and it can be found in the queue-4.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
>From 4097461897df91041382ff6fcd2bfa7ee6b2448c Mon Sep 17 00:00:00 2001
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: Mon, 25 Jul 2016 11:36:54 -0700
Subject: Input: i8042 - break load dependency between atkbd/psmouse and i8042
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
commit 4097461897df91041382ff6fcd2bfa7ee6b2448c upstream.
As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.
> hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
> driver like atkbd.c. atkbd.c depends on libps2.c because it invokes
> ps2_command(). libps2.c depends on i8042.c because it invokes
> i8042_check_port_owner(). As a result, hyperv_keyboard actually
> depends on i8042.c.
>
> For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
> Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
> rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
> no i8042 device emulated) and finally hyperv_keyboard can't work and
> the user can't input: https://bugs.archlinux.org/task/39820
> (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)
To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.
Reported-by: Mark Laws <mdl@60hz.org>
Tested-by: Mark Laws <mdl@60hz.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/input/serio/i8042.c | 16 +---------------
drivers/input/serio/libps2.c | 10 ++++------
include/linux/i8042.h | 6 ------
include/linux/serio.h | 24 +++++++++++++++++++-----
4 files changed, 24 insertions(+), 32 deletions(-)
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -1277,6 +1277,7 @@ static int __init i8042_create_kbd_port(
serio->start = i8042_start;
serio->stop = i8042_stop;
serio->close = i8042_port_close;
+ serio->ps2_cmd_mutex = &i8042_mutex;
serio->port_data = port;
serio->dev.parent = &i8042_platform_device->dev;
strlcpy(serio->name, "i8042 KBD port", sizeof(serio->name));
@@ -1373,21 +1374,6 @@ static void i8042_unregister_ports(void)
}
}
-/*
- * Checks whether port belongs to i8042 controller.
- */
-bool i8042_check_port_owner(const struct serio *port)
-{
- int i;
-
- for (i = 0; i < I8042_NUM_PORTS; i++)
- if (i8042_ports[i].serio == port)
- return true;
-
- return false;
-}
-EXPORT_SYMBOL(i8042_check_port_owner);
-
static void i8042_free_irqs(void)
{
if (i8042_aux_irq_registered)
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -56,19 +56,17 @@ EXPORT_SYMBOL(ps2_sendbyte);
void ps2_begin_command(struct ps2dev *ps2dev)
{
- mutex_lock(&ps2dev->cmd_mutex);
+ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
- if (i8042_check_port_owner(ps2dev->serio))
- i8042_lock_chip();
+ mutex_lock(m);
}
EXPORT_SYMBOL(ps2_begin_command);
void ps2_end_command(struct ps2dev *ps2dev)
{
- if (i8042_check_port_owner(ps2dev->serio))
- i8042_unlock_chip();
+ struct mutex *m = ps2dev->serio->ps2_cmd_mutex ?: &ps2dev->cmd_mutex;
- mutex_unlock(&ps2dev->cmd_mutex);
+ mutex_unlock(m);
}
EXPORT_SYMBOL(ps2_end_command);
--- a/include/linux/i8042.h
+++ b/include/linux/i8042.h
@@ -62,7 +62,6 @@ struct serio;
void i8042_lock_chip(void);
void i8042_unlock_chip(void);
int i8042_command(unsigned char *param, int command);
-bool i8042_check_port_owner(const struct serio *);
int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio));
int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
@@ -83,11 +82,6 @@ static inline int i8042_command(unsigned
return -ENODEV;
}
-static inline bool i8042_check_port_owner(const struct serio *serio)
-{
- return false;
-}
-
static inline int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio))
{
--- a/include/linux/serio.h
+++ b/include/linux/serio.h
@@ -31,7 +31,8 @@ struct serio {
struct serio_device_id id;
- spinlock_t lock; /* protects critical sections from port's interrupt handler */
+ /* Protects critical sections from port's interrupt handler */
+ spinlock_t lock;
int (*write)(struct serio *, unsigned char);
int (*open)(struct serio *);
@@ -40,16 +41,29 @@ struct serio {
void (*stop)(struct serio *);
struct serio *parent;
- struct list_head child_node; /* Entry in parent->children list */
+ /* Entry in parent->children list */
+ struct list_head child_node;
struct list_head children;
- unsigned int depth; /* level of nesting in serio hierarchy */
+ /* Level of nesting in serio hierarchy */
+ unsigned int depth;
- struct serio_driver *drv; /* accessed from interrupt, must be protected by serio->lock and serio->sem */
- struct mutex drv_mutex; /* protects serio->drv so attributes can pin driver */
+ /*
+ * serio->drv is accessed from interrupt handlers; when modifying
+ * caller should acquire serio->drv_mutex and serio->lock.
+ */
+ struct serio_driver *drv;
+ /* Protects serio->drv so attributes can pin current driver */
+ struct mutex drv_mutex;
struct device dev;
struct list_head node;
+
+ /*
+ * For use by PS/2 layer when several ports share hardware and
+ * may get indigestion when exposed to concurrent access (i8042).
+ */
+ struct mutex *ps2_cmd_mutex;
};
#define to_serio_port(d) container_of(d, struct serio, dev)
Patches currently in stable-queue which might be from dmitry.torokhov@gmail.com are
queue-4.7/input-elan_i2c-properly-wake-up-touchpad-on-asus-laptops.patch
queue-4.7/input-i8042-break-load-dependency-between-atkbd-psmouse-and-i8042.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2016-09-05 14:29 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-09-05 14:29 Patch "Input: i8042 - break load dependency between atkbd/psmouse and i8042" has been added to the 4.7-stable tree gregkh
-- strict thread matches above, loose matches on Subject: below --
2016-08-18 13:14 gregkh
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.