kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 146 insertions, 0 deletions

diff --git a/drivers/phy/rockchip/Kconfig b/drivers/phy/rockchip/Kconfig
new file mode 100644
index 000000000..14698571b
--- /dev/null
+++ b/drivers/phy/rockchip/Kconfig
@@ -0,0 +1,146 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Phy drivers for Rockchip platforms
+#
+config PHY_ROCKCHIP_DP
+	tristate "Rockchip Display Port PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip Display Port PHY.
+
+config PHY_ROCKCHIP_DPHY_RX0
+	tristate "Rockchip MIPI Synopsys DPHY RX0 driver"
+	depends on ARCH_ROCKCHIP || COMPILE_TEST
+	select GENERIC_PHY_MIPI_DPHY
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip MIPI Synopsys DPHY RX0
+	  associated to the Rockchip ISP module present in RK3399 SoCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called phy-rockchip-dphy-rx0.
+
+config PHY_ROCKCHIP_EMMC
+	tristate "Rockchip EMMC PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip EMMC PHY.
+
+config PHY_ROCKCHIP_INNO_HDMI
+	tristate "Rockchip INNO HDMI PHY Driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+	depends on COMMON_CLK
+	depends on HAS_IOMEM
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip Innosilicon HDMI PHY.
+
+config PHY_ROCKCHIP_INNO_USB2
+	tristate "Rockchip INNO USB2PHY Driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+	depends on COMMON_CLK
+	depends on EXTCON
+	depends on USB_SUPPORT
+	select GENERIC_PHY
+	select USB_COMMON
+	help
+	  Support for Rockchip USB2.0 PHY with Innosilicon IP block.
+
+config PHY_ROCKCHIP_INNO_CSIDPHY
+	tristate "Rockchip Innosilicon MIPI CSI PHY driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+	select GENERIC_PHY
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Enable this to support the Rockchip MIPI CSI PHY with
+	  Innosilicon IP block.
+
+config PHY_ROCKCHIP_INNO_DSIDPHY
+	tristate "Rockchip Innosilicon MIPI/LVDS/TTL PHY driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+	select GENERIC_PHY
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Enable this to support the Rockchip MIPI/LVDS/TTL PHY with
+	  Innosilicon IP block.
+
+config PHY_ROCKCHIP_NANENG_COMBO_PHY
+	tristate "Rockchip NANENG COMBO PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip PCIe/USB3.0/SATA/QSGMII
+	  combo PHY with NaNeng IP block.
+
+config PHY_ROCKCHIP_PCIE
+	tristate "Rockchip PCIe PHY Driver"
+	depends on (ARCH_ROCKCHIP && OF) || COMPILE_TEST
+	depends on HAS_IOMEM
+	select GENERIC_PHY
+	select MFD_SYSCON
+	help
+	  Enable this to support the Rockchip PCIe PHY.
+
+config PHY_ROCKCHIP_SAMSUNG_DCPHY
+	tristate "Rockchip Samsung MIPI DCPHY driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST)
+	select GENERIC_PHY
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Enable this to support the Rockchip MIPI DCPHY with
+	  Samsung IP block.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called phy-rockchip-samsung-dcphy
+
+config PHY_ROCKCHIP_SAMSUNG_HDPTX
+	tristate "Rockchip Samsung HDMI/eDP Combo PHY driver"
+	depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
+	depends on COMMON_CLK
+	depends on HAS_IOMEM
+	select GENERIC_PHY
+	select MFD_SYSCON
+	select RATIONAL
+	help
+	  Enable this to support the Rockchip HDMI/eDP Combo PHY
+	  with Samsung IP block.
+
+config PHY_ROCKCHIP_SNPS_PCIE3
+	tristate "Rockchip Snps PCIe3 PHY Driver"
+	depends on (ARCH_ROCKCHIP && OF) || COMPILE_TEST
+	depends on HAS_IOMEM
+	select GENERIC_PHY
+	select MFD_SYSCON
+	help
+	  Enable this to support the Rockchip snps PCIe3 PHY.
+
+config PHY_ROCKCHIP_TYPEC
+	tristate "Rockchip TYPEC PHY Driver"
+	depends on OF && (ARCH_ROCKCHIP || COMPILE_TEST)
+	select EXTCON
+	select GENERIC_PHY
+	select RESET_CONTROLLER
+	help
+	  Enable this to support the Rockchip USB TYPEC PHY.
+
+config PHY_ROCKCHIP_USB
+	tristate "Rockchip USB2 PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	select GENERIC_PHY
+	help
+	  Enable this to support the Rockchip USB 2.0 PHY.
+
+config PHY_ROCKCHIP_USBDP
+	tristate "Rockchip USBDP COMBO PHY Driver"
+	depends on ARCH_ROCKCHIP && OF
+	depends on TYPEC
+	select GENERIC_PHY
+	select USB_COMMON
+	help
+	  Enable this to support the Rockchip USB3.0/DP combo PHY with
+	  Samsung IP block. This is required for USB3 support on RK3588.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called phy-rockchip-usbdp