[Crash-utility] Re: [PATCH] arm64: support an X86_64 target on an ARM64 host

Hi Boiko, On 10/5/26 3:44 AM, Boiko Alex wrote: > On Sat, Oct 3, 2026 at 9:26 AM Dave Young <yangrr.2009(a)tsinghua.org.cn&gt; > wrote: > >> >> >> On 10/3/26 3:20 PM, Dave Young wrote: >>> >>> >>> On 10/3/26 1:32 PM, Dave Young wrote: >>>> Hi Boiko, >>>> >>>> I will review it. But please resend via either embed the patch in >> email body via email client (not an attachment), or send it via git >> send-email. >>> >>> Copy some comments here, but please make sure to send plain text inline >> patch as above (use git send-email for safe if you are not sure how to >> setup email clients). >>> >>> /* necessary header files */ >>> typedef unsigned int u32; >>> +#if defined(X86_64) && !defined(__x86_64__) >>> +#include "lkcd_x86_64_pt_regs.h" /* for pt_regs >> */ >>> +#else >>> #include <asm/ptrace.h> /* for pt_regs >> */ >>> +#endif >>> >>> >>> Above chunk is unreachable. That #include sits inside below if condition: >>> #if defined(ARM) || defined(X86) || defined(PPC) || defined(S390) || \ >>> defined(S390X) || defined(ARM64) || defined(MIPS) || \ >>> defined(MIPS64) || defined(SPARC64) || defined(RISCV64) || \ >>> defined(LOONGARCH64) >>> >>> >>> 2. Remove TARGET_CFLAGS_X86_64_ON_ARM64 as it is identical to the >> TARGET_CFLAGS_X86_64 >>> >>> 3. machine_type("X86") in filesys.c is unreachable: configure.c never >> allows target=X86 on an arm64 host. Harmless defensive symmetry. >>> >>> >>> 4. lkcd_x86_64_pt_regs.h: Copyright line is wrong (2025), please remove >> or update it. >> >> >> 5. below chunk is not for supporting x86_64 on arm64, please separate it >> in another patch: >> if ((target_data.initial_gdb_target == ARM64) && >> (target_data.target != ARM64)) { >> - if (target_data.target == X86_64) >> + if ((target_data.target == X86_64) && >> + (target_data.host == X86_64)) >> target_data.target = ARM64; >> else >> arch_mismatch(sp); >> > > without it, would be wrong gdb arch and wrong build after native arm64 > build, so it directly related Ok, it confuses sometimes, I thought about the host checking. how about make it clearer like below: if ((target_data.initial_gdb_target == ARM64) && (target_data.target != ARM64)) { if (target_data.host == ARM64) { /* * The gdb in this tree is a native ARM64 gdb; it cannot * serve any other target, so a clean rebuild is required. */ arch_mismatch(sp); } else if (target_data.host == X86_64 && target_data.target == X86_64) { /* * An ARM64 cross gdb built on an X86_64 host is sticky. */ target_data.target = ARM64; } else arch_mismatch(sp); } > > $ make target=x86_64 lzo snappy zstd >> >> TARGET: ARM64 >> >> CRASH: 9.0.3++ >> >> GDB: 16.2 >> >> >> >> gcc -c -g -DARM64 -DLZO -DSNAPPY -DZSTD -DGDB_16_2 build_data.c >> >> gcc -c -g -DARM64 -DLZO -DSNAPPY -DZSTD -DGDB_16_2 diskdump.c >> >> ar -rs crashlib.a main.o tools.o global_data.o memory.o filesys.o help.o >> task.o build_data.o kernel.o test.o gdb_interface.o net.o dev.o bpf.o >> printk.o alpha.o x86.o ppc.o ia64.o s390.o s390x.o s390dbf.o ppc64.o >> x86_64.o arm.o arm64.o mips.o mips64.o riscv64.o loongarch64.o sparc64.o >> extensions.o remote.o va_server.o va_server_v1.o symbols.o cmdline.o >> lkcd_common.o lkcd_v1.o lkcd_v2_v3.o lkcd_v5.o lkcd_v7.o lkcd_v8.o >> lkcd_fix_mem.o s390_dump.o netdump.o diskdump.o makedumpfile.o xendump.o >> lkcd_x86_trace.o unwind_v1.o unwind_v2.o unwind_v3.o unwind_x86_32_64.o >> unwind_arm.o xen_hyper.o xen_hyper_command.o xen_hyper_global_data.o >> xen_hyper_dump_tables.o kvmdump.o qemu.o qemu-load.o sadump.o ipcs.o >> ramdump.o vmware_vmss.o vmware_guestdump.o xen_dom0.o kaslr_helper.o >> sbitmap.o maple_tree.o lzorle_decompress.o >> make[4]: warning: Clock skew detected. Your build may be incomplete. >> >> CXXLD gdb >> > > > > instead of > > >> $make target=x86_64 lzo snappy zstd >> >> >> >> The initial build in this source tree was for the ARM64 architecture. >> >> >> >> In order to build a crash binary for the X86_64 architecture: >> >> 1. remove the gdb-16.2 subdirectory >> >> 2. perform a "make clean" >> >> 3. retry the build >> > > > > make: *** [Makefile:306: all] Error 1 > >> >>> >>> >>>> >>>> On 10/2/26 10:33 PM, Boiko Alex wrote: >>>>> >>>>> >>>>> >>>>> -- >>>>> Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io >>>>> To unsubscribe send an email to >> devel-leave(a)lists.crash-utility.osci.io >>>>> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ >>>>> Contribution Guidelines: https://github.com/crash-utility/crash/wiki >>>> -- >>>> Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io >>>> To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io >>>> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ >>>> Contribution Guidelines: https://github.com/crash-utility/crash/wiki >>> -- >>> Crash-utility mailing list -- devel(a)lists.crash-utility.osci.io >>> To unsubscribe send an email to devel-leave(a)lists.crash-utility.osci.io >>> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/ >>> Contribution Guidelines: https://github.com/crash-utility/crash/wiki >> >> >