From 8445a87f7092bc8336ea1305be9306f26b846d93 Mon Sep 17 00:00:00 2001 From: "Guilherme G. Piccoli" Date: Mon, 11 Apr 2016 16:17:23 -0300 Subject: [PATCH] powerpc/iommu: Remove the dependency on EEH struct in DDW mechanism Commit 39baadbf36ce ("powerpc/eeh: Remove eeh information from pci_dn") changed the pci_dn struct by removing its EEH-related members. As part of this clean-up, DDW mechanism was modified to read the device configuration address from eeh_dev struct. As a consequence, now if we disable EEH mechanism on kernel command-line for example, the DDW mechanism will fail, generating a kernel oops by dereferencing a NULL pointer (which turns to be the eeh_dev pointer). This patch just changes the configuration address calculation on DDW functions to a manual calculation based on pci_dn members instead of using eeh_dev-based address. No functional changes were made. This was tested on pSeries, both in PHyp and qemu guest. Fixes: 39baadbf36ce ("powerpc/eeh: Remove eeh information from pci_dn") Cc: stable@vger.kernel.org # v3.4+ Reviewed-by: Gavin Shan Signed-off-by: Guilherme G. Piccoli Signed-off-by: Michael Ellerman --- arch/powerpc/platforms/pseries/iommu.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index bd98ce2be17b..b7dfc1359d01 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -912,7 +912,8 @@ machine_arch_initcall(pseries, find_existing_ddw_windows); static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail, struct ddw_query_response *query) { - struct eeh_dev *edev; + struct device_node *dn; + struct pci_dn *pdn; u32 cfg_addr; u64 buid; int ret; @@ -923,11 +924,10 @@ static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail, * Retrieve them from the pci device, not the node with the * dma-window property */ - edev = pci_dev_to_eeh_dev(dev); - cfg_addr = edev->config_addr; - if (edev->pe_config_addr) - cfg_addr = edev->pe_config_addr; - buid = edev->phb->buid; + dn = pci_device_to_OF_node(dev); + pdn = PCI_DN(dn); + buid = pdn->phb->buid; + cfg_addr = (pdn->busno << 8) | pdn->devfn; ret = rtas_call(ddw_avail[0], 3, 5, (u32 *)query, cfg_addr, BUID_HI(buid), BUID_LO(buid)); @@ -941,7 +941,8 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail, struct ddw_create_response *create, int page_shift, int window_shift) { - struct eeh_dev *edev; + struct device_node *dn; + struct pci_dn *pdn; u32 cfg_addr; u64 buid; int ret; @@ -952,11 +953,10 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail, * Retrieve them from the pci device, not the node with the * dma-window property */ - edev = pci_dev_to_eeh_dev(dev); - cfg_addr = edev->config_addr; - if (edev->pe_config_addr) - cfg_addr = edev->pe_config_addr; - buid = edev->phb->buid; + dn = pci_device_to_OF_node(dev); + pdn = PCI_DN(dn); + buid = pdn->phb->buid; + cfg_addr = (pdn->busno << 8) | pdn->devfn; do { /* extra outputs are LIOBN and dma-addr (hi, lo) */ -- 2.20.1