d6c9708737
lx-dmesg needs access to the log_buf symbol from printk.c. Unfortunately, the symbol log_buf also exists in BPF's verifier.c and hence gdb can pick one or the other. If it happens to pick BPF's log_buf, lx-dmesg doesn't work: (gdb) lx-dmesg Python Exception <class 'gdb.MemoryError'> Cannot access memory at address 0x0: Error occurred in Python command: Cannot access memory at address 0x0 (gdb) p log_buf $15 = 0x0 Luckily, GDB has a way to deal with this, see https://sourceware.org/gdb/onlinedocs/gdb/Symbols.html (gdb) info variables ^log_buf$ All variables matching regular expression "^log_buf$": File <linux.git>/kernel/bpf/verifier.c: static char *log_buf; File <linux.git>/kernel/printk/printk.c: static char *log_buf; (gdb) p 'verifier.c'::log_buf $1 = 0x0 (gdb) p 'printk.c'::log_buf $2 = 0x811a6aa0 <__log_buf> "" (gdb) p &log_buf $3 = (char **) 0x8120fe40 <log_buf> (gdb) p &'verifier.c'::log_buf $4 = (char **) 0x8120fe40 <log_buf> (gdb) p &'printk.c'::log_buf $5 = (char **) 0x8048b7d0 <log_buf> By being explicit about the location of the symbol, we can make lx-dmesg work again. While at it, do the same for the other symbols we need from printk.c Link: http://lkml.kernel.org/r/20170526112222.3414-1-git@andred.net Signed-off-by: André Draszik <git@andred.net> Tested-by: Kieran Bingham <kieran@bingham.xyz> Acked-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| basic | ||
| coccinelle | ||
| dtc | ||
| gcc-plugins | ||
| gdb | ||
| genksyms | ||
| kconfig | ||
| ksymoops | ||
| mod | ||
| package | ||
| selinux | ||
| tracing | ||
| .gitignore | ||
| Kbuild.include | ||
| Lindent | ||
| Makefile | ||
| Makefile.asm-generic | ||
| Makefile.build | ||
| Makefile.clean | ||
| Makefile.dtbinst | ||
| Makefile.extrawarn | ||
| Makefile.fwinst | ||
| Makefile.gcc-plugins | ||
| Makefile.headersinst | ||
| Makefile.help | ||
| Makefile.host | ||
| Makefile.kasan | ||
| Makefile.lib | ||
| Makefile.modbuiltin | ||
| Makefile.modinst | ||
| Makefile.modpost | ||
| Makefile.modsign | ||
| Makefile.ubsan | ||
| adjust_autoksyms.sh | ||
| asn1_compiler.c | ||
| bloat-o-meter | ||
| bootgraph.pl | ||
| check-lc_ctype.c | ||
| check_00index.sh | ||
| check_extable.sh | ||
| checkincludes.pl | ||
| checkkconfigsymbols.py | ||
| checkpatch.pl | ||
| checkstack.pl | ||
| checksyscalls.sh | ||
| checkversion.pl | ||
| cleanfile | ||
| cleanpatch | ||
| coccicheck | ||
| config | ||
| conmakehash.c | ||
| const_structs.checkpatch | ||
| decode_stacktrace.sh | ||
| decodecode | ||
| depmod.sh | ||
| diffconfig | ||
| docproc.c | ||
| export_report.pl | ||
| extract-cert.c | ||
| extract-ikconfig | ||
| extract-module-sig.pl | ||
| extract-sys-certs.pl | ||
| extract-vmlinux | ||
| extract_xc3028.pl | ||
| faddr2line | ||
| gcc-goto.sh | ||
| gcc-ld | ||
| gcc-plugin.sh | ||
| gcc-version.sh | ||
| gcc-x86_32-has-stack-protector.sh | ||
| gcc-x86_64-has-stack-protector.sh | ||
| gen_initramfs_list.sh | ||
| get_dvb_firmware | ||
| get_maintainer.pl | ||
| gfp-translate | ||
| headerdep.pl | ||
| headers.sh | ||
| headers_check.pl | ||
| headers_install.sh | ||
| insert-sys-cert.c | ||
| kallsyms.c | ||
| kernel-doc | ||
| kernel-doc-xml-ref | ||
| ld-version.sh | ||
| link-vmlinux.sh | ||
| makelst | ||
| markup_oops.pl | ||
| mkcompile_h | ||
| mkmakefile | ||
| mksysmap | ||
| mkuboot.sh | ||
| mkversion | ||
| module-common.lds | ||
| namespace.pl | ||
| objdiff | ||
| patch-kernel | ||
| pnmtologo.c | ||
| profile2linkerlist.pl | ||
| prune-kernel | ||
| recordmcount.c | ||
| recordmcount.h | ||
| recordmcount.pl | ||
| setlocalversion | ||
| show_delta | ||
| sign-file.c | ||
| sortextable.c | ||
| sortextable.h | ||
| spelling.txt | ||
| stackdelta | ||
| stackusage | ||
| tags.sh | ||
| unifdef.c | ||
| ver_linux | ||
| xen-hypercalls.sh | ||
| xz_wrap.sh | ||