# git rev-parse -q --verify f8b2336f15f3bc30e37ce5c052cde5b6319bb6df^{commit} f8b2336f15f3bc30e37ce5c052cde5b6319bb6df already have revision, skipping fetch # git checkout -q -f -B kisskb f8b2336f15f3bc30e37ce5c052cde5b6319bb6df # git clean -qxdf # < git log -1 # commit f8b2336f15f3bc30e37ce5c052cde5b6319bb6df # Author: Michael Ellerman # Date: Wed Feb 22 00:03:31 2023 +1100 # # powerpc: Avoid dead code/data elimination when using recordmcount # # Although powerpc now has objtool mcount support, it's not enabled in all # configurations due to dependencies. # # On those configurations, with some linkers (binutils 2.37 at least), # it's still possible to hit the dreaded "recordmcount bug", eg. errors # such as: # # CC kernel/kexec_file.o # Cannot find symbol for section 10: .text.unlikely. # kernel/kexec_file.o: failed # make[1]: *** [scripts/Makefile.build:287 : kernel/kexec_file.o] Error 1 # # Those errors are much more prevalent when building with # CONFIG_LD_DEAD_CODE_DATA_ELIMINATION, because it places every function # in a separate section. # # CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is marked experimental and is not # enabled in any powerpc defconfigs or by major distros. Although it does # have at least some users on 32-bit where kernel size tends to be more # important. # # Avoid the build errors by blocking CONFIG_LD_DEAD_CODE_DATA_ELIMINATION # when the build is using recordmcount, rather than objtool. In practice # that means for 64-bit big endian builds, or 64-bit clang builds - both # because they lack CONFIG_MPROFILE_KERNEL. # # On 32-bit objtool is always used, so # CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is still available there. # # Signed-off-by: Michael Ellerman # Link: https://lore.kernel.org/r/20230221130331.2714199-1-mpe@ellerman.id.au # < /opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version # < /opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version # < git log --format=%s --max-count=1 f8b2336f15f3bc30e37ce5c052cde5b6319bb6df # < make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig+KVM_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- mpc85xx_defconfig # Added to kconfig CONFIG_PPC_E500MC=y # Added to kconfig CONFIG_VIRTUALIZATION=y # Added to kconfig CONFIG_KVM_E500MC=y # Added to kconfig # < make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig+KVM_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- help # make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig+KVM_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- olddefconfig .config:4474:warning: override: reassigning to symbol PPC_E500MC .config:4475:warning: override: reassigning to symbol VIRTUALIZATION # make -s -j 32 ARCH=powerpc O=/kisskb/build/powerpc-fixes_mpc85xx_defconfig+KVM_powerpc-gcc12 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux- In file included from /kisskb/src/include/linux/build_bug.h:5, from /kisskb/src/include/linux/container_of.h:5, from /kisskb/src/include/linux/list.h:5, from /kisskb/src/include/linux/module.h:12, from /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:15: /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c: In function 'allocate_bd': /kisskb/src/include/linux/err.h:22:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 22 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO) | ^ /kisskb/src/include/linux/compiler.h:78:45: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ /kisskb/src/drivers/net/ethernet/freescale/fs_enet/mac-scc.c:139:13: note: in expansion of macro 'IS_ERR_VALUE' 139 | if (IS_ERR_VALUE(fep->ring_mem_addr)) | ^~~~~~~~~~~~ /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8541cds.dts:341.15-350.5: Warning (pci_device_reg): /pci@e0008000/i8259@19000: PCI unit address format error, expected "12,0" /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8541cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8555cds.dts:341.15-350.5: Warning (pci_device_reg): /pci@e0008000/i8259@19000: PCI unit address format error, expected "12,0" /kisskb/src/arch/powerpc/boot/dts/fsl/mpc8555cds.dts:330.3-21: Warning (pci_device_bus_num): /pci@e0008000/i8259@19000:bus-range: PCI bus number 1 out of range, expected (0 - 0) Completed OK # rm -rf /kisskb/build/powerpc-fixes_mpc85xx_defconfig+KVM_powerpc-gcc12 # Build took: 0:02:17.778843