diff mbox series

PCI: Restrict device disabled status check to DT

Message ID 20230419193513.708818-1-robh@kernel.org
State New
Headers
Series PCI: Restrict device disabled status check to DT |

Commit Message

Rob Herring April 19, 2023, 7:35 p.m. UTC 
  Commit 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
checked the firmware device status for both DT and ACPI devices. That
caused a regression in some ACPI systems. The exact reason isn't clear.
It's possibly a firmware bug. For now, at least, refactor the check to
be for DT based systems only.

Note that the original implementation leaked a refcount which is now
correctly handled.

Fixes: 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
Link: https://lore.kernel.org/all/m2fs9lgndw.fsf@gmail.com/
Reported-by: Donald Hunter <donald.hunter@gmail.com>
Cc: Binbin Zhou <zhoubinbin@loongson.cn>
Cc: Liu Peibao <liupeibao@loongson.cn>
Cc: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Rob Herring <robh@kernel.org>
---
 drivers/pci/of.c    | 30 ++++++++++++++++++++++++------
 drivers/pci/pci.h   |  4 ++--
 drivers/pci/probe.c |  8 ++++----
 3 files changed, 30 insertions(+), 12 deletions(-)

Comments

Bjorn Helgaas April 19, 2023, 8:20 p.m. UTC | #1 
[+cc Vitaly, Jesse, Tony, Andy, regressions, regarding reports of
hang or crash during boot in igb driver, some with AWS Xen]

On Wed, Apr 19, 2023 at 02:35:13PM -0500, Rob Herring wrote:
> Commit 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
> checked the firmware device status for both DT and ACPI devices. That
> caused a regression in some ACPI systems. The exact reason isn't clear.
> It's possibly a firmware bug. For now, at least, refactor the check to
> be for DT based systems only.
> 
> Note that the original implementation leaked a refcount which is now
> correctly handled.
> 
> Fixes: 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
> Link: https://lore.kernel.org/all/m2fs9lgndw.fsf@gmail.com/
> Reported-by: Donald Hunter <donald.hunter@gmail.com>
> Cc: Binbin Zhou <zhoubinbin@loongson.cn>
> Cc: Liu Peibao <liupeibao@loongson.cn>
> Cc: Huacai Chen <chenhuacai@loongson.cn>
> Signed-off-by: Rob Herring <robh@kernel.org>

Applied to for-linus for (hopefully) v6.3.  I added:

  [bhelgaas: Per ACPI r6.5, sec 6.3.7, for devices on an enumerable
  bus, _STA must return with bit[0] ("device is present") set]

  Link: https://bugzilla.kernel.org/show_bug.cgi?id=217317

It would be really great if anybody who has seen this issue could test
and report whether this patch solves it.

> ---
>  drivers/pci/of.c    | 30 ++++++++++++++++++++++++------
>  drivers/pci/pci.h   |  4 ++--
>  drivers/pci/probe.c |  8 ++++----
>  3 files changed, 30 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/pci/of.c b/drivers/pci/of.c
> index 196834ed44fe..4c2ef2e28fb5 100644
> --- a/drivers/pci/of.c
> +++ b/drivers/pci/of.c
> @@ -16,14 +16,32 @@
>  #include "pci.h"
>  
>  #ifdef CONFIG_PCI
> -void pci_set_of_node(struct pci_dev *dev)
> +/**
> + * pci_set_of_node - Find and set device's DT device_node
> + * @dev: the PCI device structure to fill
> + *
> + * Returns 0 on success with of_node set or when no device is described in the
> + * DT. Returns -ENODEV if the device is present, but disabled in the DT.
> + */
> +int pci_set_of_node(struct pci_dev *dev)
>  {
> +	struct device_node *node;
> +
>  	if (!dev->bus->dev.of_node)
> -		return;
> -	dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
> -						    dev->devfn);
> -	if (dev->dev.of_node)
> -		dev->dev.fwnode = &dev->dev.of_node->fwnode;
> +		return 0;
> +
> +	node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
> +	if (!node)
> +		return 0;
> +
> +	if (!of_device_is_available(node)) {
> +		of_node_put(node);
> +		return -ENODEV;
> +	}
> +
> +	dev->dev.of_node = node;
> +	dev->dev.fwnode = &node->fwnode;
> +	return 0;
>  }
>  
>  void pci_release_of_node(struct pci_dev *dev)
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index d2c08670a20e..2b48a0aa8008 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -624,7 +624,7 @@ int of_pci_get_max_link_speed(struct device_node *node);
>  u32 of_pci_get_slot_power_limit(struct device_node *node,
>  				u8 *slot_power_limit_value,
>  				u8 *slot_power_limit_scale);
> -void pci_set_of_node(struct pci_dev *dev);
> +int pci_set_of_node(struct pci_dev *dev);
>  void pci_release_of_node(struct pci_dev *dev);
>  void pci_set_bus_of_node(struct pci_bus *bus);
>  void pci_release_bus_of_node(struct pci_bus *bus);
> @@ -662,7 +662,7 @@ of_pci_get_slot_power_limit(struct device_node *node,
>  	return 0;
>  }
>  
> -static inline void pci_set_of_node(struct pci_dev *dev) { }
> +static inline int pci_set_of_node(struct pci_dev *dev) { return 0; }
>  static inline void pci_release_of_node(struct pci_dev *dev) { }
>  static inline void pci_set_bus_of_node(struct pci_bus *bus) { }
>  static inline void pci_release_bus_of_node(struct pci_bus *bus) { }
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index a3f68b6ba6ac..f96fa83f2627 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -1826,7 +1826,7 @@ int pci_setup_device(struct pci_dev *dev)
>  	u32 class;
>  	u16 cmd;
>  	u8 hdr_type;
> -	int pos = 0;
> +	int err, pos = 0;
>  	struct pci_bus_region region;
>  	struct resource *res;
>  
> @@ -1840,10 +1840,10 @@ int pci_setup_device(struct pci_dev *dev)
>  	dev->error_state = pci_channel_io_normal;
>  	set_pcie_port_type(dev);
>  
> -	pci_set_of_node(dev);
> +	err = pci_set_of_node(dev);
> +	if (err)
> +		return err;
>  	pci_set_acpi_fwnode(dev);
> -	if (dev->dev.fwnode && !fwnode_device_is_available(dev->dev.fwnode))
> -		return -ENODEV;
>  
>  	pci_dev_assign_slot(dev);
>  
> -- 
> 2.39.2
>
Donald Hunter April 20, 2023, 7:14 a.m. UTC | #2 
On Wed, 19 Apr 2023 at 20:45, Rob Herring <robh@kernel.org> wrote:
>
> Commit 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
> checked the firmware device status for both DT and ACPI devices. That
> caused a regression in some ACPI systems. The exact reason isn't clear.
> It's possibly a firmware bug. For now, at least, refactor the check to
> be for DT based systems only.
>
> Note that the original implementation leaked a refcount which is now
> correctly handled.
>
> Fixes: 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
> Link: https://lore.kernel.org/all/m2fs9lgndw.fsf@gmail.com/
> Reported-by: Donald Hunter <donald.hunter@gmail.com>
> Cc: Binbin Zhou <zhoubinbin@loongson.cn>
> Cc: Liu Peibao <liupeibao@loongson.cn>
> Cc: Huacai Chen <chenhuacai@loongson.cn>
> Signed-off-by: Rob Herring <robh@kernel.org>

Tested-by: Donald Hunter <donald.hunter@gmail.com>

Thanks!

> ---
>  drivers/pci/of.c    | 30 ++++++++++++++++++++++++------
>  drivers/pci/pci.h   |  4 ++--
>  drivers/pci/probe.c |  8 ++++----
>  3 files changed, 30 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/pci/of.c b/drivers/pci/of.c
> index 196834ed44fe..4c2ef2e28fb5 100644
> --- a/drivers/pci/of.c
> +++ b/drivers/pci/of.c
> @@ -16,14 +16,32 @@
>  #include "pci.h"
>
>  #ifdef CONFIG_PCI
> -void pci_set_of_node(struct pci_dev *dev)
> +/**
> + * pci_set_of_node - Find and set device's DT device_node
> + * @dev: the PCI device structure to fill
> + *
> + * Returns 0 on success with of_node set or when no device is described in the
> + * DT. Returns -ENODEV if the device is present, but disabled in the DT.
> + */
> +int pci_set_of_node(struct pci_dev *dev)
>  {
> +       struct device_node *node;
> +
>         if (!dev->bus->dev.of_node)
> -               return;
> -       dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
> -                                                   dev->devfn);
> -       if (dev->dev.of_node)
> -               dev->dev.fwnode = &dev->dev.of_node->fwnode;
> +               return 0;
> +
> +       node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
> +       if (!node)
> +               return 0;
> +
> +       if (!of_device_is_available(node)) {
> +               of_node_put(node);
> +               return -ENODEV;
> +       }
> +
> +       dev->dev.of_node = node;
> +       dev->dev.fwnode = &node->fwnode;
> +       return 0;
>  }
>
>  void pci_release_of_node(struct pci_dev *dev)
> diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> index d2c08670a20e..2b48a0aa8008 100644
> --- a/drivers/pci/pci.h
> +++ b/drivers/pci/pci.h
> @@ -624,7 +624,7 @@ int of_pci_get_max_link_speed(struct device_node *node);
>  u32 of_pci_get_slot_power_limit(struct device_node *node,
>                                 u8 *slot_power_limit_value,
>                                 u8 *slot_power_limit_scale);
> -void pci_set_of_node(struct pci_dev *dev);
> +int pci_set_of_node(struct pci_dev *dev);
>  void pci_release_of_node(struct pci_dev *dev);
>  void pci_set_bus_of_node(struct pci_bus *bus);
>  void pci_release_bus_of_node(struct pci_bus *bus);
> @@ -662,7 +662,7 @@ of_pci_get_slot_power_limit(struct device_node *node,
>         return 0;
>  }
>
> -static inline void pci_set_of_node(struct pci_dev *dev) { }
> +static inline int pci_set_of_node(struct pci_dev *dev) { return 0; }
>  static inline void pci_release_of_node(struct pci_dev *dev) { }
>  static inline void pci_set_bus_of_node(struct pci_bus *bus) { }
>  static inline void pci_release_bus_of_node(struct pci_bus *bus) { }
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index a3f68b6ba6ac..f96fa83f2627 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -1826,7 +1826,7 @@ int pci_setup_device(struct pci_dev *dev)
>         u32 class;
>         u16 cmd;
>         u8 hdr_type;
> -       int pos = 0;
> +       int err, pos = 0;
>         struct pci_bus_region region;
>         struct resource *res;
>
> @@ -1840,10 +1840,10 @@ int pci_setup_device(struct pci_dev *dev)
>         dev->error_state = pci_channel_io_normal;
>         set_pcie_port_type(dev);
>
> -       pci_set_of_node(dev);
> +       err = pci_set_of_node(dev);
> +       if (err)
> +               return err;
>         pci_set_acpi_fwnode(dev);
> -       if (dev->dev.fwnode && !fwnode_device_is_available(dev->dev.fwnode))
> -               return -ENODEV;
>
>         pci_dev_assign_slot(dev);
>
> --
> 2.39.2
>
Vitaly Kuznetsov April 20, 2023, 9:30 a.m. UTC | #3 
Bjorn Helgaas <helgaas@kernel.org> writes:

> [+cc Vitaly, Jesse, Tony, Andy, regressions, regarding reports of
> hang or crash during boot in igb driver, some with AWS Xen]
>
> On Wed, Apr 19, 2023 at 02:35:13PM -0500, Rob Herring wrote:
>> Commit 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
>> checked the firmware device status for both DT and ACPI devices. That
>> caused a regression in some ACPI systems. The exact reason isn't clear.
>> It's possibly a firmware bug. For now, at least, refactor the check to
>> be for DT based systems only.
>> 
>> Note that the original implementation leaked a refcount which is now
>> correctly handled.
>> 
>> Fixes: 6fffbc7ae137 ("PCI: Honor firmware's device disabled status")
>> Link: https://lore.kernel.org/all/m2fs9lgndw.fsf@gmail.com/
>> Reported-by: Donald Hunter <donald.hunter@gmail.com>
>> Cc: Binbin Zhou <zhoubinbin@loongson.cn>
>> Cc: Liu Peibao <liupeibao@loongson.cn>
>> Cc: Huacai Chen <chenhuacai@loongson.cn>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>
> Applied to for-linus for (hopefully) v6.3.  I added:
>
>   [bhelgaas: Per ACPI r6.5, sec 6.3.7, for devices on an enumerable
>   bus, _STA must return with bit[0] ("device is present") set]
>
>   Link: https://bugzilla.kernel.org/show_bug.cgi?id=217317
>
> It would be really great if anybody who has seen this issue could test
> and report whether this patch solves it.
>

[Cc: Myron]

I can confirm the patch fixes the issue I've reported with AWS Xen
instances, so:

Tested-by:  Vitaly Kuznetsov <vkuznets@redhat.com>
diff mbox series

Patch

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 196834ed44fe..4c2ef2e28fb5 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -16,14 +16,32 @@ 
 #include "pci.h"
 
 #ifdef CONFIG_PCI
-void pci_set_of_node(struct pci_dev *dev)
+/**
+ * pci_set_of_node - Find and set device's DT device_node
+ * @dev: the PCI device structure to fill
+ *
+ * Returns 0 on success with of_node set or when no device is described in the
+ * DT. Returns -ENODEV if the device is present, but disabled in the DT.
+ */
+int pci_set_of_node(struct pci_dev *dev)
 {
+	struct device_node *node;
+
 	if (!dev->bus->dev.of_node)
-		return;
-	dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
-						    dev->devfn);
-	if (dev->dev.of_node)
-		dev->dev.fwnode = &dev->dev.of_node->fwnode;
+		return 0;
+
+	node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
+	if (!node)
+		return 0;
+
+	if (!of_device_is_available(node)) {
+		of_node_put(node);
+		return -ENODEV;
+	}
+
+	dev->dev.of_node = node;
+	dev->dev.fwnode = &node->fwnode;
+	return 0;
 }
 
 void pci_release_of_node(struct pci_dev *dev)
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index d2c08670a20e..2b48a0aa8008 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -624,7 +624,7 @@  int of_pci_get_max_link_speed(struct device_node *node);
 u32 of_pci_get_slot_power_limit(struct device_node *node,
 				u8 *slot_power_limit_value,
 				u8 *slot_power_limit_scale);
-void pci_set_of_node(struct pci_dev *dev);
+int pci_set_of_node(struct pci_dev *dev);
 void pci_release_of_node(struct pci_dev *dev);
 void pci_set_bus_of_node(struct pci_bus *bus);
 void pci_release_bus_of_node(struct pci_bus *bus);
@@ -662,7 +662,7 @@  of_pci_get_slot_power_limit(struct device_node *node,
 	return 0;
 }
 
-static inline void pci_set_of_node(struct pci_dev *dev) { }
+static inline int pci_set_of_node(struct pci_dev *dev) { return 0; }
 static inline void pci_release_of_node(struct pci_dev *dev) { }
 static inline void pci_set_bus_of_node(struct pci_bus *bus) { }
 static inline void pci_release_bus_of_node(struct pci_bus *bus) { }
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index a3f68b6ba6ac..f96fa83f2627 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1826,7 +1826,7 @@  int pci_setup_device(struct pci_dev *dev)
 	u32 class;
 	u16 cmd;
 	u8 hdr_type;
-	int pos = 0;
+	int err, pos = 0;
 	struct pci_bus_region region;
 	struct resource *res;
 
@@ -1840,10 +1840,10 @@  int pci_setup_device(struct pci_dev *dev)
 	dev->error_state = pci_channel_io_normal;
 	set_pcie_port_type(dev);
 
-	pci_set_of_node(dev);
+	err = pci_set_of_node(dev);
+	if (err)
+		return err;
 	pci_set_acpi_fwnode(dev);
-	if (dev->dev.fwnode && !fwnode_device_is_available(dev->dev.fwnode))
-		return -ENODEV;
 
 	pci_dev_assign_slot(dev);