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Resolving a kernel panic RIP to a source line

Given a panic line such as drm_atomic_connector_get_property+0x1a3/0x340, nm + addr2line map the symbol and offset back to a file:line. scripts/ga and scripts/pa wrap those two steps.

TL;DR

  • You need a vmlinux with symbols — build the kernel at least once.
  • Manual: nm vmlinux | grep <symbol> → add the offset → addr2line -e vmlinux -i <addr>.
  • Or: scripts/ga <vmlinux> <symbol+offset> prints the first addr2line line (-i inline expansions are cut, so you get the outermost frame).
  • scripts/pa <file>:<line> [context] prints context lines before/after with the target line highlighted in red (default 8).
  • Addresses and line numbers are build-specific; the example below is a historical observation from the documented WSL2 kernel and will not match a different build.

Manual path

nm <kernel-src>/vmlinux | grep drm_atomic_connector_get_property
# ffffffff81d67c10 t drm_atomic_connector_get_property
# ffffffff81d67c00 t __pfx_drm_atomic_connector_get_property

# ffffffff81d67c10 + 0x1a3 = ffffffff81d67db3

addr2line -e <kernel-src>/vmlinux -i ffffffff81d67db3
# <kernel-src>/drivers/gpu/drm/drm_atomic_uapi.c:808

awk 'NR>=800 && NR<=816 {print NR, $0}' \
  <kernel-src>/drivers/gpu/drm/drm_atomic_uapi.c

The symbol lookup excludes __-prefixed symbols, which is why __pfx_drm_atomic_connector_get_property (the function-prefix padding) is not the one that gets used.

With the helper scripts

# resolve the RIP to a file:line
./scripts/ga <kernel-src>/vmlinux drm_atomic_connector_get_property+0x1a3
# <kernel-src>/drivers/gpu/drm/drm_atomic_uapi.c:808

# print 8 lines before and after file:line, highlighting the target line
./scripts/pa <kernel-src>/drivers/gpu/drm/drm_atomic_uapi.c:808

Both scripts accept --help and use the workspace exit codes (see scripts/ga, scripts/pa).

Get the crash log

WSL stores crash dumps under %LOCALAPPDATA%\Temp\wsl-crashes on the Windows side; open the most recent kernel-panic-xxxxxxxx.txt.

Caveats

  • The ffffffff81d67c10 / +0x1a3 / drm_atomic_uapi.c:808 values above are a single historical observation on the documented WSL2 kernel; symbol addresses and line numbers change with every build and config.
  • The source excerpt that the original tutorial showed at line 808 is omitted here on purpose: it belongs to one kernel revision and would drift again.

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