Building on the lineinfo series, this adds typed function parameter display to oops and WARN dumps. A build-time tool extracts parameter names and types from DWARF, and the kernel maps pt_regs to the calling convention at crash time. When BTF is available, struct pointer parameters are dereferenced and their members displayed.
Example output from a WARN in a function receiving struct new_utsname * (kernel version info) and struct file * parameters: ------------[ cut here ]------------ WARNING: drivers/tty/sysrq.c:1209 at demo_crash+0xf/0x20 (drivers/tty/sysrq.c:1209) CPU: 2 UID: 0 PID: 323 Comm: bash RIP: 0010:demo_crash+0xf/0x20 (drivers/tty/sysrq.c:1209) ... RDI: ffffffffb8ca8d00 RSI: ffffa0a3c250acc0 ... Function parameters (paraminfo_demo_crash): uts (struct new_utsname *) = 0xffffffffb8ca8d00 .sysname = "Linux" .nodename = "localhost" .release = "7.0.0-rc2-00006-g3190..." .version = "#45 SMP PRE" file (struct file * ) = 0xffffa0a3c250acc0 .f_mode = (fmode_t)67993630 .f_op = (struct file_operations *)0xffffffffb7237620 .f_flags = (unsigned int)32769 .f_cred = (struct cred *)0xffffa0a3c2e06a80 .dentry = (struct dentry *)0xffffa0a3c0978cc0 .prev_pos = (loff_t)-1 Call Trace: <TASK> write_sysrq_trigger+0x96/0xb0 (drivers/tty/sysrq.c:1222) proc_reg_write+0x54/0xa0 (fs/proc/inode.c:330) vfs_write+0xc9/0x480 (fs/read_write.c:686) ksys_write+0x6e/0xe0 (fs/read_write.c:738) do_syscall_64+0xe2/0x570 (arch/x86/entry/syscall_64.c:62) entry_SYSCALL_64_after_hwframe+0x77/0x7f (arch/x86/entry/entry_64.S:121) Patch 1 adds the core paraminfo infrastructure (DWARF extraction, kernel-side lookup, register-to-parameter mapping, ~1-2 MB overhead). Patch 2 adds optional BTF-based struct rendering, gated behind CONFIG_KALLSYMS_PARAMINFO_BTF. Sasha Levin (2): kallsyms: show function parameter info in oops/WARN dumps kallsyms: add BTF-based deep parameter rendering in oops dumps .../admin-guide/kallsyms-lineinfo.rst | 31 + arch/x86/kernel/dumpstack.c | 6 +- include/linux/kallsyms.h | 9 + init/Kconfig | 40 ++ kernel/Makefile | 1 + kernel/kallsyms.c | 182 ++++++ kernel/kallsyms_internal.h | 6 + kernel/kallsyms_paraminfo_btf.c | 199 ++++++ lib/Kconfig.debug | 11 + lib/tests/Makefile | 3 + lib/tests/paraminfo_kunit.c | 249 ++++++++ scripts/Makefile | 3 + scripts/empty_paraminfo.S | 18 + scripts/gen_paraminfo.c | 597 ++++++++++++++++++ scripts/link-vmlinux.sh | 44 +- 15 files changed, 1393 insertions(+), 6 deletions(-) create mode 100644 kernel/kallsyms_paraminfo_btf.c create mode 100644 lib/tests/paraminfo_kunit.c create mode 100644 scripts/empty_paraminfo.S create mode 100644 scripts/gen_paraminfo.c -- 2.51.0
