From: Sumit Semwal Date: Sat, 25 Mar 2017 16:18:12 +0000 (+0530) Subject: PCI: Do any VF BAR updates before enabling the BARs X-Git-Tag: release-20171130_firefly~4^2~100^2~1^2~20^2~10 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4110080574acd69677c869ba49207150c09c9c0f;p=firefly-linux-kernel-4.4.55.git PCI: Do any VF BAR updates before enabling the BARs From: Gavin Shan [ Upstream commit f40ec3c748c6912f6266c56a7f7992de61b255ed ] Previously we enabled VFs and enable their memory space before calling pcibios_sriov_enable(). But pcibios_sriov_enable() may update the VF BARs: for example, on PPC PowerNV we may change them to manage the association of VFs to PEs. Because 64-bit BARs cannot be updated atomically, it's unsafe to update them while they're enabled. The half-updated state may conflict with other devices in the system. Call pcibios_sriov_enable() before enabling the VFs so any BAR updates happen while the VF BARs are disabled. [bhelgaas: changelog] Tested-by: Carol Soto Signed-off-by: Gavin Shan Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sumit Semwal Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 47c46d07f110..357527712539 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -303,13 +303,6 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) return rc; } - pci_iov_set_numvfs(dev, nr_virtfn); - iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; - pci_cfg_access_lock(dev); - pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); - msleep(100); - pci_cfg_access_unlock(dev); - iov->initial_VFs = initial; if (nr_virtfn < initial) initial = nr_virtfn; @@ -320,6 +313,13 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) goto err_pcibios; } + pci_iov_set_numvfs(dev, nr_virtfn); + iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; + pci_cfg_access_lock(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + msleep(100); + pci_cfg_access_unlock(dev); + for (i = 0; i < initial; i++) { rc = virtfn_add(dev, i, 0); if (rc)