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Fix a crash from dereferencing a NULL dw_pcie_ops pointer. For example, on ARTPEC-6: Unable to handle kernel NULL pointer dereference at virtual address 00000004 pgd = c0204000 [00000004] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc3-next-20170321 #1 Hardware name: Axis ARTPEC-6 Platform task: db098000 task.stack: db096000 PC is at dw_pcie_writel_dbi+0x2c/0xd0 Prior to442ec4c04d("PCI: dwc: all: Split struct pcie_port into host-only and core structures"), every driver had a struct pcie_host_ops with function pointers, typically used as: if (pp->ops->readl_rc) return pp->ops->readl_rc(...);442ec4c04dsplit struct pcie_host_ops into two pieces: struct dw_pcie_host_ops and struct dw_pcie_ops, so the above became: if (pci->ops->readl_dbi) return pci->ops->readl_dbi(...); But pcie-artpec6.c and pcie-designware-plat.c don't need the dw_pcie_ops pointers and didn't supply a pci->ops struct, which leads to NULL pointer dereferences. Supply an empty struct dw_pcie_ops to avoid the NULL pointer dereferences. [bhelgaas: changelog] Fixes:442ec4c04d("PCI: dwc: all: Split struct pcie_port into host-only and core structures") Signed-off-by: Niklas Cassel <niklas.cassel@axis.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Kishon Vijay Abraham I <kishon@ti.com> Acked-by: Joao Pinto <jpinto@synopsys.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.