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, 74 insertions, 0 deletions

diff --git a/drivers/scsi/arm/Kconfig b/drivers/scsi/arm/Kconfig
new file mode 100644
index 000000000..9f64133f9
--- /dev/null
+++ b/drivers/scsi/arm/Kconfig
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# SCSI driver configuration for Acorn
+#
+config SCSI_ACORNSCSI_3
+	tristate "Acorn SCSI card (aka30) support"
+	depends on ARCH_ACORN && SCSI
+	select SCSI_SPI_ATTRS
+	help
+	  This enables support for the Acorn SCSI card (aka30). If you have an
+	  Acorn system with one of these, say Y. If unsure, say N.
+
+config SCSI_ACORNSCSI_SYNC
+	bool "Support SCSI 2 Synchronous Transfers"
+	depends on SCSI_ACORNSCSI_3
+	help
+	  Say Y here to enable synchronous transfer negotiation with all
+	  targets on the Acorn SCSI card.
+
+	  In general, this improves performance; however some SCSI devices
+	  don't implement it properly, so the safe answer is N.
+
+config SCSI_ARXESCSI
+	tristate "ARXE SCSI support"
+	depends on ARCH_ACORN && SCSI
+	help
+	  Around 1991, Arxe Systems Limited released a high density floppy
+	  disc interface for the Acorn Archimedes range, to allow the use of
+	  HD discs from the then new A5000 on earlier models. This interface
+	  was either sold on its own or with an integral SCSI controller.
+	  Technical details on this NCR53c94-based device are available at
+	  <http://www.cryton.demon.co.uk/acornbits/scsi_arxe.html>
+	  Say Y here to compile in support for the SCSI controller.
+
+config SCSI_CUMANA_2
+	tristate "CumanaSCSI II support"
+	depends on ARCH_ACORN && SCSI
+	help
+	  This enables support for the Cumana SCSI II card. If you have an
+	  Acorn system with one of these, say Y. If unsure, say N.
+
+config SCSI_EESOXSCSI
+	tristate "EESOX support"
+	depends on ARCH_ACORN && SCSI
+	help
+	  This enables support for the EESOX SCSI card. If you have an Acorn
+	  system with one of these, say Y, otherwise say N.
+
+config SCSI_POWERTECSCSI
+	tristate "PowerTec support"
+	depends on ARCH_ACORN && SCSI
+	help
+	  This enables support for the Powertec SCSI card on Acorn systems. If
+	  you have one of these, say Y. If unsure, say N.
+
+comment "The following drivers are not fully supported"
+	depends on ARCH_ACORN
+
+config SCSI_CUMANA_1
+	tristate "CumanaSCSI I support"
+	depends on ARCH_ACORN && SCSI
+	select SCSI_SPI_ATTRS
+	help
+	  This enables support for the Cumana SCSI I card. If you have an
+	  Acorn system with one of these, say Y. If unsure, say N.
+
+config SCSI_OAK1
+	tristate "Oak SCSI support"
+	depends on ARCH_ACORN && SCSI
+	select SCSI_SPI_ATTRS
+	help
+	  This enables support for the Oak SCSI card. If you have an Acorn
+	  system with one of these, say Y. If unsure, say N.
+