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[PATCH v3 3/7] PCI: Do not disable memory decoding in pci_reassigndev_resource_alignment()

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We should not disable memory decoding when we reassign alignment
in pci_reassigndev_resource_alignment(). It's meaningless and
have some side effect. For example, some fixup functions such as
quirk_e100_interrupt() read PCI_COMMAND_MEMORY to know whether
the devices has been initialized by the firmware or not. If we
disable memory decoding here, these functions will get a wrong
information that the devices was not initialized by the firmware
which may cause a wrong fixup. Besides, disabling memory decoding
may also break some devices that need to have memory decoding
always-on during probing.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
---
 drivers/pci/pci.c |    8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6ae02de..6241cfc 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4820,7 +4820,6 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
 	int i;
 	struct resource *r;
 	resource_size_t align, size;
-	u16 command;
 
 	/* We should never try to reassign VF's alignment */
 	if (dev->is_virtfn)
@@ -4838,12 +4837,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
 		return;
 	}
 
-	dev_info(&dev->dev,
-		"Disabling memory decoding and releasing memory resources.\n");
-	pci_read_config_word(dev, PCI_COMMAND, &command);
-	command &= ~PCI_COMMAND_MEMORY;
-	pci_write_config_word(dev, PCI_COMMAND, command);
-
+	dev_info(&dev->dev, "Releasing memory resources.\n");
 	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
 		r = &dev->resource[i];
 		if (!(r->flags & IORESOURCE_MEM))
-- 
1.7.9.5

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[PATCH v3 0/7] PCI: Add support for enforcing all MMIO BARs not to share PAGE_SIZE Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
  [PATCH v3 3/7] PCI: Do not disable memory decoding in pci_reassigndev_resource_alignment() Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
    Re: [PATCH v3 3/7] PCI: Do not disable memory decoding in  pci_reassigndev_resource_alignment() Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 03:00 +0200
      Re: [PATCH v3 3/7] PCI: Do not disable memory decoding in  pci_reassigndev_resource_alignment() Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 10:10 +0200
  [PATCH v3 1/7] PCI: Ignore enforced alignment when kernel uses existing firmware setup Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
    Re: [PATCH v3 1/7] PCI: Ignore enforced alignment when kernel uses  existing firmware setup Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 02:30 +0200
      Re: [PATCH v3 1/7] PCI: Ignore enforced alignment when kernel uses  existing firmware setup Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 06:50 +0200
  [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
    Re: [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 02:50 +0200
      Re: [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 07:30 +0200
        Re: [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 08:10 +0200
          Re: [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 08:50 +0200
            Re: [PATCH v3 2/7] PCI: Ignore enforced alignment to VF BARs Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-02 02:40 +0200
  [PATCH v3 7/7] PCI: Add a macro to set default alignment for all PCI devices Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
  [PATCH v3 4/7] PCI: Add a new option for resource_alignment to reassign alignment Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
    Re: [PATCH v3 4/7] PCI: Add a new option for resource_alignment to  reassign alignment Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 05:40 +0200
      Re: [PATCH v3 4/7] PCI: Add a new option for resource_alignment to  reassign alignment Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 09:00 +0200
  [PATCH v3 6/7] PCI: Add support for enforcing all MMIO BARs to be page aligned Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
  [PATCH v3 5/7] PCI: Do not use IORESOURCE_STARTALIGN to identify bridge resources Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-06-30 13:00 +0200
    Re: [PATCH v3 5/7] PCI: Do not use IORESOURCE_STARTALIGN to identify  bridge resources Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-01 04:40 +0200
      Re: [PATCH v3 5/7] PCI: Do not use IORESOURCE_STARTALIGN to identify  bridge resources Yongji Xie <xyjxie@linux.vnet.ibm.com> - 2016-07-01 09:10 +0200
        Re: [PATCH v3 5/7] PCI: Do not use IORESOURCE_STARTALIGN to identify  bridge resources Gavin Shan <gwshan@linux.vnet.ibm.com> - 2016-07-02 02:40 +0200

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