selftests/bpf: Reject graph kptr use after RCU unlockgrafted

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 <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/drivers/dma/sh/Kconfig b/drivers/dma/sh/Kconfig
new file mode 100644
index 000000000..a16c7e83b
--- /dev/null
+++ b/drivers/dma/sh/Kconfig
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# DMA engine configuration for sh
+#
+
+config RENESAS_DMA
+	bool
+	select DMA_ENGINE
+
+#
+# DMA Engine Helpers
+#
+
+config SH_DMAE_BASE
+	bool "Renesas SuperH DMA Engine support"
+	depends on SUPERH || COMPILE_TEST
+	depends on !SUPERH || SH_DMA
+	depends on !SH_DMA_API
+	default SUPERH || SH_DMA
+	select RENESAS_DMA
+	help
+	  Enable support for the Renesas SuperH DMA controllers.
+
+#
+# DMA Controllers
+#
+
+config SH_DMAE
+	tristate "Renesas SuperH DMAC support"
+	depends on SH_DMAE_BASE
+	help
+	  Enable support for the Renesas SuperH DMA controllers.
+
+config RCAR_DMAC
+	tristate "Renesas R-Car Gen{2,3} and RZ/G{1,2} DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	help
+	  This driver supports the general purpose DMA controller found in the
+	  Renesas R-Car Gen{2,3} and RZ/G{1,2} SoCs.
+
+config RENESAS_USB_DMAC
+	tristate "Renesas USB-DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  This driver supports the USB-DMA controller found in the Renesas
+	  SoCs.
+
+config RZ_DMAC
+	tristate "Renesas RZ DMA Controller"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select RENESAS_DMA
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  This driver supports the general purpose DMA controller typically
+	  found in the Renesas RZ SoC variants.