bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/ntb/Kconfig b/drivers/ntb/Kconfig
new file mode 100644
index 000000000..df16c755b
--- /dev/null
+++ b/drivers/ntb/Kconfig
@@ -0,0 +1,40 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig NTB
+	tristate "Non-Transparent Bridge support"
+	depends on PCI
+	help
+	 The PCI-E Non-transparent bridge hardware is a point-to-point PCI-E bus
+	 connecting 2 systems.  When configured, writes to the device's PCI
+	 mapped memory will be mirrored to a buffer on the remote system.  The
+	 ntb Linux driver uses this point-to-point communication as a method to
+	 transfer data from one system to the other.
+
+	 If unsure, say N.
+
+if NTB
+
+config NTB_MSI
+	bool "MSI Interrupt Support"
+	depends on PCI_MSI
+	help
+	 Support using MSI interrupt forwarding instead of (or in addition to)
+	 hardware doorbells. MSI interrupts typically offer lower latency
+	 than doorbells and more MSI interrupts can be made available to
+	 clients. However this requires an extra memory window and support
+	 in the hardware driver for creating the MSI interrupts.
+
+	 If unsure, say N.
+source "drivers/ntb/hw/Kconfig"
+
+source "drivers/ntb/test/Kconfig"
+
+config NTB_TRANSPORT
+	tristate "NTB Transport Client"
+	help
+	 This is a transport driver that enables connected systems to exchange
+	 messages over the ntb hardware.  The transport exposes a queue pair api
+	 to client drivers.
+
+	 If unsure, say N.
+
+endif # NTB