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ebe864b553
Livepatch needs some ELF magic which linkers don't like:
- Two relocation sections (.rela*, .klp.rela*) for the same text
section.
- Use of SHN_LIVEPATCH to mark livepatch symbols.
Unfortunately linkers tend to mangle such things. To work around that,
klp diff generates a linker-compliant intermediate binary which encodes
the relevant KLP section/reloc/symbol metadata.
After module linking, the .ko then needs to be converted to an actual
livepatch module. Introduce a new klp post-link subcommand to do so.
Acked-by: Petr Mladek <pmladek@suse.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
54 lines
1.1 KiB
C
54 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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#include <subcmd/parse-options.h>
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#include <string.h>
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#include <stdlib.h>
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#include <objtool/builtin.h>
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#include <objtool/objtool.h>
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#include <objtool/klp.h>
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struct subcmd {
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const char *name;
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const char *description;
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int (*fn)(int, const char **);
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};
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static struct subcmd subcmds[] = {
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{ "diff", "Generate binary diff of two object files", cmd_klp_diff, },
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{ "post-link", "Finalize klp symbols/relocs after module linking", cmd_klp_post_link, },
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};
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static void cmd_klp_usage(void)
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{
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fprintf(stderr, "usage: objtool klp <subcommand> [<options>]\n\n");
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fprintf(stderr, "Subcommands:\n");
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for (int i = 0; i < ARRAY_SIZE(subcmds); i++) {
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struct subcmd *cmd = &subcmds[i];
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fprintf(stderr, " %s\t%s\n", cmd->name, cmd->description);
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}
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exit(1);
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}
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int cmd_klp(int argc, const char **argv)
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{
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argc--;
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argv++;
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if (!argc)
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cmd_klp_usage();
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if (argc) {
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for (int i = 0; i < ARRAY_SIZE(subcmds); i++) {
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struct subcmd *cmd = &subcmds[i];
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if (!strcmp(cmd->name, argv[0]))
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return cmd->fn(argc, argv);
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}
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}
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cmd_klp_usage();
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return 0;
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}
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