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, 208 insertions, 0 deletions

diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
new file mode 100644
index 000000000..842c254bb
--- /dev/null
+++ b/drivers/scsi/Makefile
@@ -0,0 +1,208 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for linux/drivers/scsi
+#
+# 30 May 2000, Christoph Hellwig <hch@infradead.org>
+# Rewritten to use lists instead of if-statements.
+#
+# 20 Sep 2000, Torben Mathiasen <tmm@image.dk>
+# Changed link order to reflect new scsi initialization.
+#
+# *!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!
+# The link order must be, SCSI Core, SCSI HBA drivers, and
+# lastly SCSI peripheral drivers (disk/tape/cdrom/etc.) to
+# satisfy certain initialization assumptions in the SCSI layer.
+# *!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!*!
+
+
+CFLAGS_aha152x.o =   -DAHA152X_STAT -DAUTOCONF
+
+obj-$(CONFIG_PCMCIA)		+= pcmcia/
+
+obj-$(CONFIG_SCSI)		+= scsi_mod.o
+obj-$(CONFIG_SCSI_COMMON)	+= scsi_common.o
+
+obj-$(CONFIG_RAID_ATTRS)	+= raid_class.o
+
+obj-$(CONFIG_SCSI_PROTO_TEST)	+= scsi_proto_test.o
+
+# --- NOTE ORDERING HERE ---
+# For kernel non-modular link, transport attributes need to
+# be initialised before drivers
+# --------------------------
+obj-$(CONFIG_SCSI_SPI_ATTRS)	+= scsi_transport_spi.o
+obj-$(CONFIG_SCSI_FC_ATTRS) 	+= scsi_transport_fc.o
+obj-$(CONFIG_SCSI_ISCSI_ATTRS)	+= scsi_transport_iscsi.o
+obj-$(CONFIG_SCSI_SAS_ATTRS)	+= scsi_transport_sas.o
+obj-$(CONFIG_SCSI_SAS_LIBSAS)	+= libsas/
+obj-$(CONFIG_SCSI_SRP_ATTRS)	+= scsi_transport_srp.o
+obj-$(CONFIG_SCSI_DH)		+= device_handler/
+
+obj-$(CONFIG_LIBFC)		+= libfc/
+obj-$(CONFIG_LIBFCOE)		+= fcoe/
+obj-$(CONFIG_FCOE)		+= fcoe/
+obj-$(CONFIG_FCOE_FNIC)		+= fnic/
+obj-$(CONFIG_SCSI_SNIC)		+= snic/
+obj-$(CONFIG_SCSI_BNX2X_FCOE)	+= libfc/ fcoe/ bnx2fc/
+obj-$(CONFIG_QEDF)		+= qedf/
+obj-$(CONFIG_ISCSI_TCP) 	+= libiscsi.o	libiscsi_tcp.o iscsi_tcp.o
+obj-$(CONFIG_INFINIBAND_ISER) 	+= libiscsi.o
+obj-$(CONFIG_ISCSI_BOOT_SYSFS)	+= iscsi_boot_sysfs.o
+obj-$(CONFIG_SCSI_A4000T)	+= 53c700.o	a4000t.o
+obj-$(CONFIG_SCSI_ZORRO7XX)	+= 53c700.o	zorro7xx.o
+obj-$(CONFIG_SCSI_ZORRO_ESP)	+= esp_scsi.o	zorro_esp.o
+obj-$(CONFIG_A3000_SCSI)	+= a3000.o	wd33c93.o
+obj-$(CONFIG_A2091_SCSI)	+= a2091.o	wd33c93.o
+obj-$(CONFIG_GVP11_SCSI)	+= gvp11.o	wd33c93.o
+obj-$(CONFIG_MVME147_SCSI)	+= mvme147.o	wd33c93.o
+obj-$(CONFIG_SGIWD93_SCSI)	+= sgiwd93.o	wd33c93.o
+obj-$(CONFIG_ATARI_SCSI)	+= atari_scsi.o
+obj-$(CONFIG_MAC_SCSI)		+= mac_scsi.o
+obj-$(CONFIG_SCSI_MAC_ESP)	+= esp_scsi.o	mac_esp.o
+obj-$(CONFIG_SUN3_SCSI)		+= sun3_scsi.o  sun3_scsi_vme.o
+obj-$(CONFIG_MVME16x_SCSI)	+= 53c700.o	mvme16x_scsi.o
+obj-$(CONFIG_BVME6000_SCSI)	+= 53c700.o	bvme6000_scsi.o
+obj-$(CONFIG_SCSI_SIM710)	+= 53c700.o	sim710.o
+obj-$(CONFIG_SCSI_ADVANSYS)	+= advansys.o
+obj-$(CONFIG_SCSI_BUSLOGIC)	+= BusLogic.o
+obj-$(CONFIG_SCSI_ARCMSR)	+= arcmsr/
+obj-$(CONFIG_SCSI_AHA152X)	+= aha152x.o
+obj-$(CONFIG_SCSI_AHA1542)	+= aha1542.o
+obj-$(CONFIG_SCSI_AHA1740)	+= aha1740.o
+obj-$(CONFIG_SCSI_AIC7XXX)	+= aic7xxx/
+obj-$(CONFIG_SCSI_AIC79XX)	+= aic7xxx/
+obj-$(CONFIG_SCSI_AACRAID)	+= aacraid/
+obj-$(CONFIG_SCSI_AIC94XX)	+= aic94xx/
+obj-$(CONFIG_SCSI_PM8001)	+= pm8001/
+obj-$(CONFIG_SCSI_ISCI)		+= isci/
+obj-$(CONFIG_SCSI_IPS)		+= ips.o
+obj-$(CONFIG_SCSI_FDOMAIN)	+= fdomain.o
+obj-$(CONFIG_SCSI_FDOMAIN_PCI)	+= fdomain_pci.o
+obj-$(CONFIG_SCSI_FDOMAIN_ISA)	+= fdomain_isa.o
+obj-$(CONFIG_SCSI_GENERIC_NCR5380) += g_NCR5380.o
+obj-$(CONFIG_SCSI_QLOGIC_FAS)	+= qlogicfas408.o	qlogicfas.o
+obj-$(CONFIG_PCMCIA_QLOGIC)	+= qlogicfas408.o
+obj-$(CONFIG_SCSI_QLOGIC_1280)	+= qla1280.o 
+obj-$(CONFIG_SCSI_QLA_FC)	+= qla2xxx/
+obj-$(CONFIG_SCSI_QLA_ISCSI)	+= libiscsi.o qla4xxx/
+obj-$(CONFIG_SCSI_LPFC)		+= lpfc/
+obj-$(CONFIG_SCSI_EFCT)		+= elx/
+obj-$(CONFIG_SCSI_BFA_FC)	+= bfa/
+obj-$(CONFIG_SCSI_CHELSIO_FCOE)	+= csiostor/
+obj-$(CONFIG_SCSI_DMX3191D)	+= dmx3191d.o
+obj-$(CONFIG_SCSI_HPSA)		+= hpsa.o
+obj-$(CONFIG_SCSI_SMARTPQI)	+= smartpqi/
+obj-$(CONFIG_SCSI_SYM53C8XX_2)	+= sym53c8xx_2/
+obj-$(CONFIG_SCSI_ZALON)	+= zalon7xx.o
+obj-$(CONFIG_SCSI_DC395x)	+= dc395x.o
+obj-$(CONFIG_SCSI_AM53C974)	+= esp_scsi.o	am53c974.o
+obj-$(CONFIG_MEGARAID_LEGACY)	+= megaraid.o
+obj-$(CONFIG_MEGARAID_NEWGEN)	+= megaraid/
+obj-$(CONFIG_MEGARAID_SAS)	+= megaraid/
+obj-$(CONFIG_SCSI_MPT3SAS)	+= mpt3sas/
+obj-$(CONFIG_SCSI_MPI3MR)	+= mpi3mr/
+obj-$(CONFIG_SCSI_ACARD)	+= atp870u.o
+obj-$(CONFIG_SCSI_SUNESP)	+= esp_scsi.o	sun_esp.o
+obj-$(CONFIG_SCSI_INITIO)	+= initio.o
+obj-$(CONFIG_SCSI_INIA100)	+= a100u2w.o
+obj-$(CONFIG_SCSI_QLOGICPTI)	+= qlogicpti.o
+obj-$(CONFIG_SCSI_MESH)		+= mesh.o
+obj-$(CONFIG_SCSI_MAC53C94)	+= mac53c94.o
+obj-$(CONFIG_SCSI_MYRB)		+= myrb.o
+obj-$(CONFIG_SCSI_MYRS)		+= myrs.o
+obj-$(CONFIG_BLK_DEV_3W_XXXX_RAID) += 3w-xxxx.o
+obj-$(CONFIG_SCSI_3W_9XXX)	+= 3w-9xxx.o
+obj-$(CONFIG_SCSI_3W_SAS)	+= 3w-sas.o
+obj-$(CONFIG_SCSI_PPA)		+= ppa.o
+obj-$(CONFIG_SCSI_IMM)		+= imm.o
+obj-$(CONFIG_JAZZ_ESP)		+= esp_scsi.o	jazz_esp.o
+obj-$(CONFIG_SUN3X_ESP)		+= esp_scsi.o	sun3x_esp.o
+obj-$(CONFIG_SCSI_LASI700)	+= 53c700.o lasi700.o
+obj-$(CONFIG_SCSI_SNI_53C710)	+= 53c700.o sni_53c710.o
+obj-$(CONFIG_SCSI_NSP32)	+= nsp32.o
+obj-$(CONFIG_SCSI_IPR)		+= ipr.o
+obj-$(CONFIG_SCSI_IBMVSCSI)	+= ibmvscsi/
+obj-$(CONFIG_SCSI_IBMVSCSIS)	+= ibmvscsi_tgt/
+obj-$(CONFIG_SCSI_IBMVFC)	+= ibmvscsi/
+obj-$(CONFIG_SCSI_HPTIOP)	+= hptiop.o
+obj-$(CONFIG_SCSI_STEX)		+= stex.o
+obj-$(CONFIG_SCSI_MVSAS)	+= mvsas/
+obj-$(CONFIG_SCSI_MVUMI)	+= mvumi.o
+obj-$(CONFIG_PS3_ROM)		+= ps3rom.o
+obj-$(CONFIG_SCSI_CXGB3_ISCSI)	+= libiscsi.o libiscsi_tcp.o cxgbi/
+obj-$(CONFIG_SCSI_CXGB4_ISCSI)	+= libiscsi.o libiscsi_tcp.o cxgbi/
+obj-$(CONFIG_SCSI_BNX2_ISCSI)	+= libiscsi.o bnx2i/
+obj-$(CONFIG_QEDI)          += libiscsi.o qedi/
+obj-$(CONFIG_BE2ISCSI)		+= libiscsi.o be2iscsi/
+obj-$(CONFIG_SCSI_ESAS2R)	+= esas2r/
+obj-$(CONFIG_SCSI_PMCRAID)	+= pmcraid.o
+obj-$(CONFIG_SCSI_VIRTIO)	+= virtio_scsi.o
+obj-$(CONFIG_VMWARE_PVSCSI)	+= vmw_pvscsi.o
+obj-$(CONFIG_XEN_SCSI_FRONTEND)	+= xen-scsifront.o
+obj-$(CONFIG_HYPERV_STORAGE)	+= hv_storvsc.o
+obj-$(CONFIG_SCSI_WD719X)	+= wd719x.o
+
+obj-$(CONFIG_ARM)		+= arm/
+
+obj-$(CONFIG_CHR_DEV_ST)	+= st.o
+obj-$(CONFIG_BLK_DEV_SD)	+= sd_mod.o
+obj-$(CONFIG_BLK_DEV_SR)	+= sr_mod.o
+obj-$(CONFIG_CHR_DEV_SG)	+= sg.o
+obj-$(CONFIG_CHR_DEV_SCH)	+= ch.o
+obj-$(CONFIG_SCSI_ENCLOSURE)	+= ses.o
+
+obj-$(CONFIG_SCSI_HISI_SAS) += hisi_sas/
+
+# This goes last, so that "real" scsi devices probe earlier
+obj-$(CONFIG_SCSI_DEBUG)	+= scsi_debug.o
+scsi_mod-y			+= scsi.o hosts.o scsi_ioctl.o \
+				   scsicam.o scsi_error.o scsi_lib.o
+scsi_mod-$(CONFIG_SCSI_CONSTANTS) += constants.o
+scsi_mod-$(CONFIG_SCSI_DMA)	+= scsi_lib_dma.o
+scsi_mod-y			+= scsi_scan.o scsi_sysfs.o scsi_devinfo.o
+scsi_mod-$(CONFIG_SCSI_NETLINK)	+= scsi_netlink.o
+scsi_mod-$(CONFIG_SYSCTL)	+= scsi_sysctl.o
+scsi_mod-$(CONFIG_SCSI_PROC_FS)	+= scsi_proc.o
+scsi_mod-$(CONFIG_BLK_DEBUG_FS)	+= scsi_debugfs.o
+scsi_mod-y			+= scsi_trace.o scsi_logging.o
+scsi_mod-$(CONFIG_PM)		+= scsi_pm.o
+scsi_mod-$(CONFIG_SCSI_DH)	+= scsi_dh.o
+scsi_mod-$(CONFIG_BLK_DEV_BSG)	+= scsi_bsg.o
+
+hv_storvsc-y			:= storvsc_drv.o
+
+sd_mod-objs	:= sd.o
+sd_mod-$(CONFIG_BLK_DEV_INTEGRITY) += sd_dif.o
+sd_mod-$(CONFIG_BLK_DEV_ZONED) += sd_zbc.o
+
+sr_mod-objs	:= sr.o sr_ioctl.o sr_vendor.o
+ncr53c8xx-flags-$(CONFIG_SCSI_ZALON) \
+		:= -DNCR53C8XX_PREFETCH -DSCSI_NCR_BIG_ENDIAN \
+			-DSCSI_NCR53C8XX_NO_WORD_TRANSFERS
+CFLAGS_ncr53c8xx.o	:= $(ncr53c8xx-flags-y) $(ncr53c8xx-flags-m)
+zalon7xx-objs	:= zalon.o ncr53c8xx.o
+
+# Files generated that shall be removed upon make clean
+clean-files :=	53c700_d.h 53c700_u.h
+
+$(obj)/53c700.o: $(obj)/53c700_d.h
+
+$(obj)/scsi_sysfs.o: $(obj)/scsi_devinfo_tbl.c
+
+quiet_cmd_bflags = GEN     $@
+	cmd_bflags = sed -n 's/.*define *BLIST_\([A-Z0-9_]*\) *.*/BLIST_FLAG_NAME(\1),/p' $< > $@
+
+$(obj)/scsi_devinfo_tbl.c: include/scsi/scsi_devinfo.h FORCE
+	$(call if_changed,bflags)
+
+targets +=  scsi_devinfo_tbl.c
+
+# If you want to play with the firmware, uncomment
+# GENERATE_FIRMWARE := 1
+
+ifdef GENERATE_FIRMWARE
+
+$(obj)/53c700_d.h: $(src)/53c700.scr $(src)/script_asm.pl
+	$(PERL) -s $(src)/script_asm.pl -ncr7x0_family $@ $(@:_d.h=_u.h) < $<
+
+endif