4.18-stable review patch. If anyone has any objections, please let me know.
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From: Sam Bobroff sbobroff@linux.ibm.com
[ Upstream commit b87b9cf4935325c98522823caeddd333022a1c62 ]
EEH recovery currently fails on pSeries for some IOV capable PCI devices, if CONFIG_PCI_IOV is on and the hypervisor doesn't provide certain device tree properties for the device. (Found on an IOV capable device using the ipr driver.)
Recovery fails in pci_enable_resources() at the check on r->parent, because r->flags is set and r->parent is not. This state is due to sriov_init() setting the start, end and flags members of the IOV BARs but the parent not being set later in pseries_pci_fixup_iov_resources(), because the "ibm,open-sriov-vf-bar-info" property is missing.
Correct this by zeroing the resource flags for IOV BARs when they can't be configured (this is the same method used by sriov_init() and __pci_read_base()).
VFs cleared this way can't be enabled later, because that requires another device tree property, "ibm,number-of-configurable-vfs" as well as support for the RTAS function "ibm_map_pes". These are all part of hypervisor support for IOV and it seems unlikely that a hypervisor would ever partially, but not fully, support it. (None are currently provided by QEMU/KVM.)
Signed-off-by: Sam Bobroff sbobroff@linux.ibm.com Reviewed-by: Bryant G. Ly bryantly@linux.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/platforms/pseries/setup.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-)
--- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -647,6 +647,15 @@ void of_pci_parse_iov_addrs(struct pci_d } }
+static void pseries_disable_sriov_resources(struct pci_dev *pdev) +{ + int i; + + pci_warn(pdev, "No hypervisor support for SR-IOV on this device, IOV BARs disabled.\n"); + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) + pdev->resource[i + PCI_IOV_RESOURCES].flags = 0; +} + static void pseries_pci_fixup_resources(struct pci_dev *pdev) { const int *indexes; @@ -654,10 +663,10 @@ static void pseries_pci_fixup_resources(
/*Firmware must support open sriov otherwise dont configure*/ indexes = of_get_property(dn, "ibm,open-sriov-vf-bar-info", NULL); - if (!indexes) - return; - /* Assign the addresses from device tree*/ - of_pci_set_vf_bar_size(pdev, indexes); + if (indexes) + of_pci_set_vf_bar_size(pdev, indexes); + else + pseries_disable_sriov_resources(pdev); }
static void pseries_pci_fixup_iov_resources(struct pci_dev *pdev) @@ -669,10 +678,10 @@ static void pseries_pci_fixup_iov_resour return; /*Firmware must support open sriov otherwise dont configure*/ indexes = of_get_property(dn, "ibm,open-sriov-vf-bar-info", NULL); - if (!indexes) - return; - /* Assign the addresses from device tree*/ - of_pci_parse_iov_addrs(pdev, indexes); + if (indexes) + of_pci_parse_iov_addrs(pdev, indexes); + else + pseries_disable_sriov_resources(pdev); }
static resource_size_t pseries_pci_iov_resource_alignment(struct pci_dev *pdev,