linux-stable-sw-v4.19.180-sw64-2203.tar.gz 编译错误排查方法
出现：
AR arch/sw_64/chip/chip3/built-in.a AR arch/sw_64/chip/built-in.a CC kernel/futex.o {standard input}: Assembler messages: {standard input}:8070: ??? lstw and rd_f the first register must be the same {standard input}:8453: ??? lstw and rd_f the first register must be the same {standard input}:8629: ??? lstw and rd_f the first register must be the same {standard input}:8665: ??? lstw and rd_f the first register must be the same {standard input}:8693: ??? lstw and rd_f the first register must be the same make[1]: *** [scripts/Makefile.build:304?kernel/futex.o] ?? 1这个看不懂原因，大概是两个指令的寄存器必须一致吧，而这个指令在哪呢？
打开make的调试日志
make ARCH=sw_64 CROSS_COMPILE=sw_64-sunway-linux-gnu- V=1 >x.txt查看最后输出的命令
sw_64-sunway-linux-gnu-gcc -Wp,-MD,kernel/.futex.o.d -nostdinc -isystem /opt/swgcc/usr/bin/../lib/gcc/sw_64-sunway-linux-gnu/10.3.0/include -I./arch/sw_64/include -I./arch/sw_64/include/generated -I./include -I./arch/sw_64/include/uapi -I./arch/sw_64/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h -include ./include/linux/compiler_types.h -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -fshort-wchar -Werror-implicit-function-declaration -Werror=return-type -Wno-format-security -std=gnu89 -fno-PIE -pipe -ffixed-8 -mno-fp-regs -fno-jump-tables -fno-delete-null-pointer-checks -Wno-frame-address -Wno-format-truncation -Wno-format-overflow -Wno-int-in-bool-context -Wno-address-of-packed-member -O2 -fno-allow-store-data-races -Wframe-larger-than=2048 -fno-stack-protector -Wno-unused-but-set-variable -Wno-unused-const-variable -fno-omit-frame-pointer -fno-optimize-sibling-calls -fno-var-tracking-assignments -Wdeclaration-after-statement -Wno-pointer-sign -Wno-stringop-truncation -Wno-zero-length-bounds -Wno-array-bounds -Wno-stringop-overflow -Wno-restrict -Wno-maybe-uninitialized -fno-strict-overflow -fno-merge-all-constants -fmerge-constants -fno-stack-check -fconserve-stack -Werror=implicit-int -Werror=strict-prototypes -Werror=date-time -Werror=incompatible-pointer-types -Werror=designated-init -fmacro-prefix-map=./= -Wno-packed-not-aligned -DKBUILD_BASENAME='"futex"' -DKBUILD_MODNAME='"futex"' -c -o kernel/.tmp_futex.o kernel/futex.c
将这个命令改成编译出汇编
sw_64-sunway-linux-gnu-gcc -Wp,-MD,kernel/.futex.o.d -nostdinc -isystem /opt/swgcc/usr/bin/../lib/gcc/sw_64-sunway-linux-gnu/10.3.0/include -I./arch/sw_64/include -I./arch/sw_64/include/generated -I./include -I./arch/sw_64/include/uapi -I./arch/sw_64/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h -include ./include/linux/compiler_types.h -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -fshort-wchar -Werror-implicit-function-declaration -Werror=return-type -Wno-format-security -std=gnu89 -fno-PIE -pipe -ffixed-8 -mno-fp-regs -fno-jump-tables -fno-delete-null-pointer-checks -Wno-frame-address -Wno-format-truncation -Wno-format-overflow -Wno-int-in-bool-context -Wno-address-of-packed-member -O2 -fno-allow-store-data-races -Wframe-larger-than=2048 -fno-stack-protector -Wno-unused-but-set-variable -Wno-unused-const-variable -fno-omit-frame-pointer -fno-optimize-sibling-calls -fno-var-tracking-assignments -Wdeclaration-after-statement -Wno-pointer-sign -Wno-stringop-truncation -Wno-zero-length-bounds -Wno-array-bounds -Wno-stringop-overflow -Wno-restrict -Wno-maybe-uninitialized -fno-strict-overflow -fno-merge-all-constants -fmerge-constants -fno-stack-check -fconserve-stack -Werror=implicit-int -Werror=strict-prototypes -Werror=date-time -Werror=incompatible-pointer-types -Werror=designated-init -fmacro-prefix-map=./= -Wno-packed-not-aligned-DKBUILD_BASENAME='"futex"' -DKBUILD_MODNAME='"futex"' -c -o kernel/.tmp_futex.S -S kernel/futex.c
查看汇编的8070行
代码来自 futex.h，仔细对照能找到对应的函数
下面我们从linux-stable-sw-v5.10.229-sw1.3.0.tar.gz 这个代码中找对应的函数，因为linux-stable-sw-v5.10.229-sw1.3.0.tar.gz是可以编译通过的
#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg, tmp) \ __asm__ __volatile__( \ "1: lldw %0, 0(%3)\n" \ " ldi %2, 1\n" \ " wr_f %2\n" \ insn \ "2: lstw %1, 0(%3)\n" \ " rd_f %1\n" \ " beq %1, 4f\n" \ " bis $31, $31, %1\n" \ "3: .subsection 2\n" \ "4: br 1b\n" \ " .previous\n" \ " .section __ex_table, \"a\"\n" \ " .long 1b-.\n" \ " ldi $31, 3b-1b(%1)\n" \ " .long 2b-.\n" \ " ldi $31, 3b-2b(%1)\n" \ " .previous\n" \ : "=&r" (oldval), "=&r"(ret), "=&r"(tmp) \ : "r" (uaddr), "r"(oparg) \ : "memory")果然不一样了，然后将这个代码修改过去即可
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qemu执行内核的代码
#!/bin/bash bin/qemu-system-sw64 \ -M core3 \ -cpu core3 \ -m 4G \ -smp 1\ -name vm001 \ -kernel ./vmlinux \ -drive file=./busybox.qcow2,if=virtio \ -append "root=/dev/vda rw console=ttyS0 ignore_loglevel notc init=/init" \ -d int,guest_errors -D a.log \ -device VGA \ -serial stdio \ -monitor telnet:localhost:7100,server,nowait,nodelay \ -s内核编译时注意dtb要采用内嵌的，名字是chip_vt