Hi Alexandr, On 10/7/26 9:13 PM, Alexandr Boyko wrote: > Allow "make target=X86_64" on an arm64 host to analyze x86_64 dumpfiles, > mirroring the existing "make target=ARM64" support on an x86_64 host. > > The only host dependency was in the LKCD dump headers, which embed a > "struct pt_regs" from <asm/ptrace.h>. The arm64 uapi header exports > "struct user_pt_regs" instead, so add lkcd_x86_64_pt_regs.h, a copy of > the x86_64 uapi definition used only when the X86_64 target is built on > a non-x86_64 host. > > Also make the sticky target logic host aware, and reject live system > debugging of an X86/X86_64 binary on an arm64 host. > > Assisted-by: Github Copilot CLI:claude-opus-5 > Signed-off-by: Alexander Boyko <boy1284(a)gmail.com&gt; > --- > Makefile | 2 +- > README | 2 ++ > configure.c | 36 +++++++++++++++++++++++++++--- > filesys.c | 4 ++++ > lkcd_vmdump_v1.h | 4 ++++ > lkcd_vmdump_v2_v3.h | 4 ++++ > lkcd_x86_64_pt_regs.h | 51 +++++++++++++++++++++++++++++++++++++++++++ > 7 files changed, 99 insertions(+), 4 deletions(-) > create mode 100644 lkcd_x86_64_pt_regs.h > > diff --git a/Makefile b/Makefile > index 46c43a4..22154af 100644 > --- a/Makefile > +++ b/Makefile > @@ -98,7 +98,7 @@ GENERIC_HFILES=defs.h xen_hyper_defs.h xen_dom0.h > MCORE_HFILES=va_server.h vas_crash.h > REDHAT_HFILES=netdump.h diskdump.h makedumpfile.h xendump.h kvmdump.h qemu-load.h vmcore.h > LKCD_DUMP_HFILES=lkcd_vmdump_v1.h lkcd_vmdump_v2_v3.h lkcd_dump_v5.h \ > - lkcd_dump_v7.h lkcd_dump_v8.h > + lkcd_dump_v7.h lkcd_dump_v8.h lkcd_x86_64_pt_regs.h > LKCD_OBSOLETE_HFILES=lkcd_fix_mem.h > LKCD_TRACE_HFILES=lkcd_x86_trace.h > IBM_HFILES=ibm_common.h > diff --git a/README b/README > index 69232eb..5c4d8f2 100644 > --- a/README > +++ b/README > @@ -113,6 +113,8 @@ > riscv64 dumpfiles may be built by typing "make target=RISCV64". > o On an x86_64 host, an x86_64 binary that can be used to analyze > loongarch64 dumpfiles may be built by typing "make target=LOONGARCH64". > + o On an arm64 host, an arm64 binary that can be used to analyze > + x86_64 dumpfiles may be built by typing "make target=X86_64". > > Traditionally when vmcores are compressed via the makedumpfile(8) facility > the libz compression library is used, and by default the crash utility > diff --git a/configure.c b/configure.c > index fd7b533..1732001 100644 > --- a/configure.c > +++ b/configure.c > @@ -182,6 +182,7 @@ void add_extra_lib(char *); > #define GDB_TARGET_MIPS_ON_X86_64 "GDB_CONF_FLAGS=--target=mipsel-elf-linux CFLAGS=-m32 CXXFLAGS=-m32" > #define GDB_TARGET_RISCV64_ON_X86_64 "GDB_CONF_FLAGS=--target=riscv64-unknown-linux-gnu" > #define GDB_TARGET_LOONGARCH64_ON_X86_64 "GDB_CONF_FLAGS=--target=loongarch64-unknown-linux-gnu" > +#define GDB_TARGET_X86_64_ON_ARM64 "GDB_CONF_FLAGS=--target=x86_64-pc-linux-gnu" > > /* > * The original plan was to allow the use of a particular version > @@ -474,6 +475,12 @@ get_current_configuration(struct supported_gdb_version *sp) > * Build an ARM64 crash binary on an X86_64 host. > */ > target_data.target = ARM64; > + } else if ((target_data.target == ARM64) && > + (name_to_target((char *)target_data.target_as_param) == X86_64)) { > + /* > + * Build an X86_64 crash binary on an ARM64 host. > + */ > + target_data.target = X86_64; > } else if ((target_data.target == X86_64) && > (name_to_target((char *)target_data.target_as_param) == PPC64)) { > /* > @@ -570,11 +577,32 @@ get_current_configuration(struct supported_gdb_version *sp) > (target_data.initial_gdb_target != X86)) > arch_mismatch(sp); > > + if ((target_data.initial_gdb_target == X86_64) && > + (target_data.target != X86_64) && > + (target_data.host == ARM64)) { > + if (target_data.target == ARM64) { > + /* > + * An X86_64 cross gdb built on an ARM64 host is sticky. > + */ > + target_data.target = X86_64; > + } else > + arch_mismatch(sp); > + } > + > if ((target_data.initial_gdb_target == ARM64) && > (target_data.target != ARM64)) { > - if (target_data.target == X86_64) > + 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 > + } else > arch_mismatch(sp); > } > if ((target_data.target == ARM64) && > @@ -787,7 +815,9 @@ build_configure(struct supported_gdb_version *sp) > break; > case X86_64: > target = TARGET_X86_64; > - target_CFLAGS = TARGET_CFLAGS_X86_64; > + target_CFLAGS = TARGET_CFLAGS_X86_64; > + if (target_data.host == ARM64) > + gdb_conf_flags = GDB_TARGET_X86_64_ON_ARM64; > break; > case ARM: > target = TARGET_ARM; > diff --git a/filesys.c b/filesys.c > index 7ff4787..f5b79e7 100644 > --- a/filesys.c > +++ b/filesys.c > @@ -4574,4 +4574,8 @@ check_live_arch_mismatch(void) > if (machine_type("PPC")) > error(FATAL, "compiled for the PPC architecture\n"); > #endif > +#ifdef __aarch64__ > + if (machine_type("X86_64")) > + error(FATAL, "compiled for the X86_64 architecture\n"); > +#endif > } > diff --git a/lkcd_vmdump_v1.h b/lkcd_vmdump_v1.h > index 3ffb219..0540a1f 100644 > --- a/lkcd_vmdump_v1.h > +++ b/lkcd_vmdump_v1.h > @@ -35,8 +35,12 @@ > #endif > #ifndef IA64 > 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 > +#endif > > /* necessary header definitions in all cases */ > #define DUMP_KIOBUF_NUMBER 0xdeadbeef /* special number for kiobuf maps */ > diff --git a/lkcd_vmdump_v2_v3.h b/lkcd_vmdump_v2_v3.h > index f215446..2b47141 100644 > --- a/lkcd_vmdump_v2_v3.h > +++ b/lkcd_vmdump_v2_v3.h > @@ -104,8 +104,12 @@ typedef struct _dump_header_asm_s { > > #ifndef IA64 > 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 > +#endif > > /* definitions */ > #define DUMP_ASM_MAGIC_NUMBER 0xdeaddeadULL /* magic number */ > diff --git a/lkcd_x86_64_pt_regs.h b/lkcd_x86_64_pt_regs.h > new file mode 100644 > index 0000000..39240d0 > --- /dev/null > +++ b/lkcd_x86_64_pt_regs.h > @@ -0,0 +1,51 @@ > +/* lkcd_x86_64_pt_regs.h - core analysis suite > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +/* > + * The LKCD dump headers embed the host kernel's "struct pt_regs", which is > + * normally picked up from <asm/ptrace.h>. When the X86_64 target is built > + * on a non-x86_64 host, that header describes the host architecture and does > + * not export an x86_64 "struct pt_regs" at all, so the definition below is > + * used instead. It is a verbatim copy of "struct pt_regs" from > + * arch/x86/include/uapi/asm/ptrace.h, which keeps the LKCD dump > + * header layout identical to a native x86_64 build. > + */ > + > +#ifndef _LKCD_X86_64_PT_REGS_H > +#define _LKCD_X86_64_PT_REGS_H > + > +struct pt_regs { > + unsigned long r15; > + unsigned long r14; > + unsigned long r13; > + unsigned long r12; > + unsigned long rbp; > + unsigned long rbx; > + unsigned long r11; > + unsigned long r10; > + unsigned long r9; > + unsigned long r8; > + unsigned long rax; > + unsigned long rcx; > + unsigned long rdx; > + unsigned long rsi; > + unsigned long rdi; > + unsigned long orig_rax; > + unsigned long rip; > + unsigned long cs; > + unsigned long eflags; > + unsigned long rsp; > + unsigned long ss; > +}; > + > +#endif /* _LKCD_X86_64_PT_REGS_H */ Thanks for the update, the patch looks good to me. Added to my apply queue.

Dave -- 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