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/arm/mach-davinci/clock.h | 61 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 arch/arm/mach-davinci/clock.h (limited to 'arch/arm/mach-davinci/clock.h') diff --git a/arch/arm/mach-davinci/clock.h b/arch/arm/mach-davinci/clock.h new file mode 100644 index 000000000..54f5663b0 --- /dev/null +++ b/arch/arm/mach-davinci/clock.h @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * TI DaVinci clock definitions + * + * Copyright (C) 2006-2007 Texas Instruments. + * Copyright (C) 2008-2009 Deep Root Systems, LLC + */ + +#ifndef __ARCH_ARM_DAVINCI_CLOCK_H +#define __ARCH_ARM_DAVINCI_CLOCK_H + +/* PLL/Reset register offsets */ +#define PLLCTL 0x100 +#define PLLCTL_PLLEN BIT(0) +#define PLLCTL_PLLPWRDN BIT(1) +#define PLLCTL_PLLRST BIT(3) +#define PLLCTL_PLLDIS BIT(4) +#define PLLCTL_PLLENSRC BIT(5) +#define PLLCTL_CLKMODE BIT(8) + +#define PLLM 0x110 +#define PLLM_PLLM_MASK 0xff + +#define PREDIV 0x114 +#define PLLDIV1 0x118 +#define PLLDIV2 0x11c +#define PLLDIV3 0x120 +#define POSTDIV 0x128 +#define BPDIV 0x12c +#define PLLCMD 0x138 +#define PLLSTAT 0x13c +#define PLLALNCTL 0x140 +#define PLLDCHANGE 0x144 +#define PLLCKEN 0x148 +#define PLLCKSTAT 0x14c +#define PLLSYSTAT 0x150 +#define PLLDIV4 0x160 +#define PLLDIV5 0x164 +#define PLLDIV6 0x168 +#define PLLDIV7 0x16c +#define PLLDIV8 0x170 +#define PLLDIV9 0x174 +#define PLLDIV_EN BIT(15) +#define PLLDIV_RATIO_MASK 0x1f + +/* + * OMAP-L138 system reference guide recommends a wait for 4 OSCIN/CLKIN + * cycles to ensure that the PLLC has switched to bypass mode. Delay of 1us + * ensures we are good for all > 4MHz OSCIN/CLKIN inputs. Typically the input + * is ~25MHz. Units are micro seconds. + */ +#define PLL_BYPASS_TIME 1 +/* From OMAP-L138 datasheet table 6-4. Units are micro seconds */ +#define PLL_RESET_TIME 1 +/* + * From OMAP-L138 datasheet table 6-4; assuming prediv = 1, sqrt(pllm) = 4 + * Units are micro seconds. + */ +#define PLL_LOCK_TIME 20 + +#endif -- cgit v1.3.1