Files
linux/scripts/livepatch/fix-patch-lines
Josh Poimboeuf 24ebfcd65a livepatch/klp-build: Introduce klp-build script for generating livepatch modules
Add a klp-build script which automates the generation of a livepatch
module from a source .patch file by performing the following steps:

  - Builds an original kernel with -function-sections and
    -fdata-sections, plus objtool function checksumming.

  - Applies the .patch file and rebuilds the kernel using the same
    options.

  - Runs 'objtool klp diff' to detect changed functions and generate
    intermediate binary diff objects.

  - Builds a kernel module which links the diff objects with some
    livepatch module init code (scripts/livepatch/init.c).

  - Finalizes the livepatch module (aka work around linker wreckage)
    using 'objtool klp post-link'.

Acked-by: Petr Mladek <pmladek@suse.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2025-10-14 14:50:19 -07:00

80 lines
1.4 KiB
Awk
Executable File

#!/usr/bin/awk -f
# SPDX-License-Identifier: GPL-2.0
#
# Use #line directives to preserve original __LINE__ numbers across patches to
# avoid unwanted compilation changes.
BEGIN {
in_hunk = 0
skip = 0
}
/^--- / {
skip = $2 !~ /\.(c|h)$/
print
next
}
/^@@/ {
if (skip) {
print
next
}
in_hunk = 1
# @@ -1,3 +1,4 @@:
# 1: line number in old file
# 3: how many lines the hunk covers in old file
# 1: line number in new file
# 4: how many lines the hunk covers in new file
match($0, /^@@ -([0-9]+)(,([0-9]+))? \+([0-9]+)(,([0-9]+))? @@/, m)
# Set 'cur' to the old file's line number at the start of the hunk. It
# gets incremented for every context line and every line removal, so
# that it always represents the old file's current line number.
cur = m[1]
# last = last line number of current hunk
last = cur + (m[3] ? m[3] : 1) - 1
need_line_directive = 0
print
next
}
{
if (skip || !in_hunk || $0 ~ /^\\ No newline at end of file/) {
print
next
}
# change line
if ($0 ~ /^[+-]/) {
# inject #line after this group of changes
need_line_directive = 1
if ($0 ~ /^-/)
cur++
print
next
}
# If this is the first context line after a group of changes, inject
# the #line directive to force the compiler to correct the line
# numbering to match the original file.
if (need_line_directive) {
print "+#line " cur
need_line_directive = 0
}
if (cur == last)
in_hunk = 0
cur++
print
}