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-gemini/Kconfig | 20 +++++++++++++ arch/arm/mach-gemini/Makefile | 3 ++ arch/arm/mach-gemini/board-dt.c | 64 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 87 insertions(+) create mode 100644 arch/arm/mach-gemini/Kconfig create mode 100644 arch/arm/mach-gemini/Makefile create mode 100644 arch/arm/mach-gemini/board-dt.c (limited to 'arch/arm/mach-gemini') diff --git a/arch/arm/mach-gemini/Kconfig b/arch/arm/mach-gemini/Kconfig new file mode 100644 index 000000000..f436a2009 --- /dev/null +++ b/arch/arm/mach-gemini/Kconfig @@ -0,0 +1,20 @@ +# SPDX-License-Identifier: GPL-2.0-only +menuconfig ARCH_GEMINI + bool "Cortina Systems Gemini" + depends on ARCH_MULTI_V4 + depends on CPU_LITTLE_ENDIAN + select ARCH_HAS_RESET_CONTROLLER + select ARM_AMBA + select ARM_APPENDED_DTB # Old Redboot bootloaders deployed + select COMMON_CLK_GEMINI + select FARADAY_FTINTC010 + select FTTMR010_TIMER + select GPIO_FTGPIO010 + select GPIOLIB + select PINCTRL + select PINCTRL_GEMINI + select POWER_RESET + select POWER_RESET_GEMINI_POWEROFF + select POWER_RESET_SYSCON + help + Support for the Cortina Systems Gemini family SoCs diff --git a/arch/arm/mach-gemini/Makefile b/arch/arm/mach-gemini/Makefile new file mode 100644 index 000000000..997a0be84 --- /dev/null +++ b/arch/arm/mach-gemini/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0-only +# Makefile for Cortina systems Gemini +obj-y := board-dt.o diff --git a/arch/arm/mach-gemini/board-dt.c b/arch/arm/mach-gemini/board-dt.c new file mode 100644 index 000000000..2bba617e4 --- /dev/null +++ b/arch/arm/mach-gemini/board-dt.c @@ -0,0 +1,64 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Gemini Device Tree boot support + */ +#include +#include +#include + +#include +#include +#include +#include + +#ifdef CONFIG_DEBUG_GEMINI +/* This is needed for LL-debug/earlyprintk/debug-macro.S */ +static struct map_desc gemini_io_desc[] __initdata = { + { + .virtual = CONFIG_DEBUG_UART_VIRT, + .pfn = __phys_to_pfn(CONFIG_DEBUG_UART_PHYS), + .length = SZ_4K, + .type = MT_DEVICE, + }, +}; + +static void __init gemini_map_io(void) +{ + iotable_init(gemini_io_desc, ARRAY_SIZE(gemini_io_desc)); +} +#else +#define gemini_map_io NULL +#endif + +static void gemini_idle(void) +{ + /* + * Because of broken hardware we have to enable interrupts or the CPU + * will never wakeup... Actually it is not very good to enable + * interrupts first since scheduler can miss a tick, but there is + * no other way around this. Platforms that needs it for power saving + * should enable it in init code, since by default it is + * disabled. + */ + + /* FIXME: Enabling interrupts here is racy! */ + raw_local_irq_enable(); + cpu_do_idle(); + raw_local_irq_disable(); +} + +static void __init gemini_init_machine(void) +{ + arm_pm_idle = gemini_idle; +} + +static const char *gemini_board_compat[] = { + "cortina,gemini", + NULL, +}; + +DT_MACHINE_START(GEMINI_DT, "Gemini (Device Tree)") + .map_io = gemini_map_io, + .init_machine = gemini_init_machine, + .dt_compat = gemini_board_compat, +MACHINE_END -- cgit v1.3.1