From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- arch/microblaze/pci/Makefile | 6 +++++ arch/microblaze/pci/iomap.c | 58 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+) create mode 100644 arch/microblaze/pci/Makefile create mode 100644 arch/microblaze/pci/iomap.c (limited to 'arch/microblaze/pci') diff --git a/arch/microblaze/pci/Makefile b/arch/microblaze/pci/Makefile new file mode 100644 index 000000000..f8267d20e --- /dev/null +++ b/arch/microblaze/pci/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile +# + +obj-$(CONFIG_PCI) += iomap.o diff --git a/arch/microblaze/pci/iomap.c b/arch/microblaze/pci/iomap.c new file mode 100644 index 000000000..b2ee8ace9 --- /dev/null +++ b/arch/microblaze/pci/iomap.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ppc64 "iomap" interface implementation. + * + * (C) Copyright 2004 Linus Torvalds + */ +#include +#include +#include +#include +#include +#include + +static DEFINE_SPINLOCK(hose_spinlock); +LIST_HEAD(hose_list); + +unsigned long isa_io_base; +EXPORT_SYMBOL(isa_io_base); + +static resource_size_t pcibios_io_size(const struct pci_controller *hose) +{ + return resource_size(&hose->io_resource); +} + +int pcibios_vaddr_is_ioport(void __iomem *address) +{ + int ret = 0; + struct pci_controller *hose; + resource_size_t size; + + spin_lock(&hose_spinlock); + list_for_each_entry(hose, &hose_list, list_node) { + size = pcibios_io_size(hose); + if (address >= hose->io_base_virt && + address < (hose->io_base_virt + size)) { + ret = 1; + break; + } + } + spin_unlock(&hose_spinlock); + return ret; +} + +/* Display the domain number in /proc */ +int pci_proc_domain(struct pci_bus *bus) +{ + return pci_domain_nr(bus); +} + +void pci_iounmap(struct pci_dev *dev, void __iomem *addr) +{ + if (isa_vaddr_is_ioport(addr)) + return; + if (pcibios_vaddr_is_ioport(addr)) + return; + iounmap(addr); +} +EXPORT_SYMBOL(pci_iounmap); -- cgit v1.3.1