On Wed, Jun 03, 2015 at 11:31:42AM +0800, Wei Yang wrote:

On Mon, Jun 01, 2015 at 06:46:45PM -0500, Bjorn Helgaas wrote:

quoted

On Tue, May 19, 2015 at 06:50:08PM +0800, Wei Yang wrote:

quoted

Current EEH recovery code works with the assumption: the PE has primary
bus. Unfortunately, that's not true to VF PEs, which generally contains
one or multiple VFs (for VF group case). The patch creates PEs for VFs
at PCI final fixup time. Those PEs for VFs are indentified with newly
introduced flag EEH_PE_VF so that we handle them differently during
EEH recovery.

[gwshan: changelog and code refactoring]
Signed-off-by: Wei Yang <redacted>
Acked-by: Gavin Shan <redacted>
---
 arch/powerpc/include/asm/eeh.h               |    1 +
 arch/powerpc/kernel/eeh_pe.c                 |   10 ++++++++--
 arch/powerpc/platforms/powernv/eeh-powernv.c |   17 +++++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 1b3614d..c1fde48 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h

@@ -70,6 +70,7 @@ struct pci_dn;
 #define EEH_PE_PHB	(1 << 1)	/* PHB PE    */
 #define EEH_PE_DEVICE 	(1 << 2)	/* Device PE */
 #define EEH_PE_BUS	(1 << 3)	/* Bus PE    */
+#define EEH_PE_VF	(1 << 4)	/* VF PE     */
 
 #define EEH_PE_ISOLATED		(1 << 0)	/* Isolated PE		*/
 #define EEH_PE_RECOVERING	(1 << 1)	/* Recovering PE	*/

diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index 35f0b62..260a701 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c

@@ -299,7 +299,10 @@ static struct eeh_pe *eeh_pe_get_parent(struct eeh_dev *edev)
 	 * EEH device already having associated PE, but
 	 * the direct parent EEH device doesn't have yet.
 	 */
-	pdn = pdn ? pdn->parent : NULL;
+	if (edev->physfn)
+		pdn = pci_get_pdn(edev->physfn);
+	else
+		pdn = pdn ? pdn->parent : NULL;
 	while (pdn) {
 		/* We're poking out of PCI territory */
 		parent = pdn_to_eeh_dev(pdn);

@@ -382,7 +385,10 @@ int eeh_add_to_parent_pe(struct eeh_dev *edev)
 	}
 
 	/* Create a new EEH PE */
-	pe = eeh_pe_alloc(edev->phb, EEH_PE_DEVICE);
+	if (edev->physfn)
+		pe = eeh_pe_alloc(edev->phb, EEH_PE_VF);
+	else
+		pe = eeh_pe_alloc(edev->phb, EEH_PE_DEVICE);
 	if (!pe) {
 		pr_err("%s: out of memory!\n", __func__);
 		return -ENOMEM;

diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
index ce738ab..c505036 100644
--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c

@@ -1520,6 +1520,23 @@ static struct eeh_ops pnv_eeh_ops = {
 	.restore_config		= pnv_eeh_restore_config
 };
 
+static void pnv_eeh_vf_final_fixup(struct pci_dev *pdev)
+{
+	struct pci_dn *pdn = pci_get_pdn(pdev);
+
+	if (!pdev->is_virtfn)
+		return;
+
+	/*
+	 * The following operations will fail if VF's sysfs files
+	 * aren't created or its resources aren't finalized.
+	 */

I don't understand this comment.  "The following operations" seems to refer
to eeh_add_device_early() and eeh_add_device_late(), and
"VF's sysfs files being created" seems to refer to eeh_sysfs_add_device().

So the comment suggests that eeh_add_device_early() and
eeh_add_device_late() will fail because they're called before
eeh_sysfs_add_device().  So I think you must be talking about some other
"following operations," not eeh_add_device_early() and
eeh_add_device_late().

Sorry for this confusion.

The comment here wants to say the eeh_sysfs_add_device() will fail if the VF's
sysfs is not created well. Or it will fail if the VF's resources are not set
properly, since we would cache the VF's BAR in eeh_add_device_late().

Gavin,

If my understanding is not correct please let me know.

It's correct. "The following operations" refers to eeh_add_device_late()
and eeh_sysfs_add_device(). The former one requires the resources for
one particular PCI device (VF here) are finalized (assigned). eeh_sysfs_add_device()
will fail if the sysfs entry for the PCI device isn't populated yet.

quoted

quoted

+	eeh_add_device_early(pdn);
+	eeh_add_device_late(pdev);
+	eeh_sysfs_add_device(pdev);
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, pnv_eeh_vf_final_fixup);

Ugh.  This is powerpc code, but I don't like using fixups as a hook like
this.  There is a pcibios_add_device() -- could this be done there?

I don't like it neither :-) But looks we can't put it in the
pcibios_add_device().

quoted

If not, what happens after pcibios_add_device() that is required for this
code?  Maybe we need a pcibios_bus_add_device() hook?

The pnv_eeh_vf_final_fixup() will try to create sysfs for VFs. This requires
the VF sysfs(kobj) is initialized properly. If we put these into
pcibios_add_device(), the eeh_sysfs_add_device() would fail.

Below is the call flow for your reference:

pci_device_add()
   pcibios_add_device()
   device_add()                <--- kobj initialized here

We can put it into pcibios_bus_add_device(), but we don't it currently. If
Bjorn agree to add pcibios_bus_add_device(), I'm fine to move the block code
there.

Thanks,
Gavin

quoted

quoted

+
 /**
  * eeh_powernv_init - Register platform dependent EEH operations
  *
-- 
1.7.9.5

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-- 
Richard Yang
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