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/mips/bcm63xx/dev-uart.c | 77 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 arch/mips/bcm63xx/dev-uart.c (limited to 'arch/mips/bcm63xx/dev-uart.c') diff --git a/arch/mips/bcm63xx/dev-uart.c b/arch/mips/bcm63xx/dev-uart.c new file mode 100644 index 000000000..5d6bf0445 --- /dev/null +++ b/arch/mips/bcm63xx/dev-uart.c @@ -0,0 +1,77 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2008 Maxime Bizon + */ + +#include +#include +#include +#include +#include + +static struct resource uart0_resources[] = { + { + /* start & end filled at runtime */ + .flags = IORESOURCE_MEM, + }, + { + /* start filled at runtime */ + .flags = IORESOURCE_IRQ, + }, +}; + +static struct resource uart1_resources[] = { + { + /* start & end filled at runtime */ + .flags = IORESOURCE_MEM, + }, + { + /* start filled at runtime */ + .flags = IORESOURCE_IRQ, + }, +}; + +static struct platform_device bcm63xx_uart_devices[] = { + { + .name = "bcm63xx_uart", + .id = 0, + .num_resources = ARRAY_SIZE(uart0_resources), + .resource = uart0_resources, + }, + + { + .name = "bcm63xx_uart", + .id = 1, + .num_resources = ARRAY_SIZE(uart1_resources), + .resource = uart1_resources, + } +}; + +int __init bcm63xx_uart_register(unsigned int id) +{ + if (id >= ARRAY_SIZE(bcm63xx_uart_devices)) + return -ENODEV; + + if (id == 1 && (!BCMCPU_IS_3368() && !BCMCPU_IS_6358() && + !BCMCPU_IS_6368())) + return -ENODEV; + + if (id == 0) { + uart0_resources[0].start = bcm63xx_regset_address(RSET_UART0); + uart0_resources[0].end = uart0_resources[0].start + + RSET_UART_SIZE - 1; + uart0_resources[1].start = bcm63xx_get_irq_number(IRQ_UART0); + } + + if (id == 1) { + uart1_resources[0].start = bcm63xx_regset_address(RSET_UART1); + uart1_resources[0].end = uart1_resources[0].start + + RSET_UART_SIZE - 1; + uart1_resources[1].start = bcm63xx_get_irq_number(IRQ_UART1); + } + + return platform_device_register(&bcm63xx_uart_devices[id]); +} -- cgit v1.3.1