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/dma/bestcomm/Kconfig | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 drivers/dma/bestcomm/Kconfig (limited to 'drivers/dma/bestcomm/Kconfig') diff --git a/drivers/dma/bestcomm/Kconfig b/drivers/dma/bestcomm/Kconfig new file mode 100644 index 000000000..5dd437295 --- /dev/null +++ b/drivers/dma/bestcomm/Kconfig @@ -0,0 +1,37 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Kconfig options for Bestcomm +# + +config PPC_BESTCOMM + tristate "Bestcomm DMA engine support" + depends on PPC_MPC52xx + default n + select PPC_LIB_RHEAP + help + BestComm is the name of the communication coprocessor found + on the Freescale MPC5200 family of processor. Its usage is + optional for some drivers (like ATA), but required for + others (like FEC). + + If you want to use drivers that require DMA operations, + answer Y or M. Otherwise say N. + +config PPC_BESTCOMM_ATA + tristate + depends on PPC_BESTCOMM + help + This option enables the support for the ATA task. + +config PPC_BESTCOMM_FEC + tristate + depends on PPC_BESTCOMM + help + This option enables the support for the FEC tasks. + +config PPC_BESTCOMM_GEN_BD + tristate + depends on PPC_BESTCOMM + help + This option enables the support for the GenBD tasks. + -- cgit v1.3.1