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 --- drivers/clk/sprd/common.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100644 drivers/clk/sprd/common.c (limited to 'drivers/clk/sprd/common.c') diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c new file mode 100644 index 000000000..0f2181617 --- /dev/null +++ b/drivers/clk/sprd/common.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Spreadtrum clock infrastructure +// +// Copyright (C) 2017 Spreadtrum, Inc. +// Author: Chunyan Zhang + +#include +#include +#include +#include +#include + +#include "common.h" + +static const struct regmap_config sprdclk_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .fast_io = true, +}; + +static void sprd_clk_set_regmap(const struct sprd_clk_desc *desc, + struct regmap *regmap) +{ + int i; + struct sprd_clk_common *cclk; + + for (i = 0; i < desc->num_clk_clks; i++) { + cclk = desc->clk_clks[i]; + if (!cclk) + continue; + + cclk->regmap = regmap; + } +} + +int sprd_clk_regmap_init(struct platform_device *pdev, + const struct sprd_clk_desc *desc) +{ + void __iomem *base; + struct device *dev = &pdev->dev; + struct device_node *node = dev->of_node, *np; + struct regmap *regmap; + struct resource *res; + struct regmap_config reg_config = sprdclk_regmap_config; + + if (of_property_present(node, "sprd,syscon")) { + regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon"); + if (IS_ERR(regmap)) { + pr_err("%s: failed to get syscon regmap\n", __func__); + return PTR_ERR(regmap); + } + } else if (of_device_is_compatible(np = of_get_parent(node), "syscon") || + (of_node_put(np), 0)) { + regmap = device_node_to_regmap(np); + of_node_put(np); + if (IS_ERR(regmap)) { + dev_err(dev, "failed to get regmap from its parent.\n"); + return PTR_ERR(regmap); + } + } else { + base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(base)) + return PTR_ERR(base); + + reg_config.max_register = resource_size(res) - reg_config.reg_stride; + + regmap = devm_regmap_init_mmio(&pdev->dev, base, + ®_config); + if (IS_ERR(regmap)) { + pr_err("failed to init regmap\n"); + return PTR_ERR(regmap); + } + } + + sprd_clk_set_regmap(desc, regmap); + + return 0; +} +EXPORT_SYMBOL_GPL(sprd_clk_regmap_init); + +int sprd_clk_probe(struct device *dev, struct clk_hw_onecell_data *clkhw) +{ + int i, ret; + struct clk_hw *hw; + + for (i = 0; i < clkhw->num; i++) { + const char *name; + + hw = clkhw->hws[i]; + if (!hw) + continue; + + name = hw->init->name; + ret = devm_clk_hw_register(dev, hw); + if (ret) { + dev_err(dev, "Couldn't register clock %d - %s\n", + i, name); + return ret; + } + } + + ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clkhw); + if (ret) + dev_err(dev, "Failed to add clock provider\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(sprd_clk_probe); + +MODULE_DESCRIPTION("Spreadtrum clock infrastructure"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1