6a997c3a23
commit 4a60aa05a0634241ce17f957bf9fb5ac1eed6576 upstream. Add support for processing switch jump tables in objects with multiple .rodata sections, such as those created by '-ffunction-sections' and '-fdata-sections'. Currently, objtool always looks in .rodata for jump table information, which results in many "sibling call from callable instruction with modified stack frame" warnings with objects compiled using those flags. The fix is comprised of three parts: 1. Flagging all .rodata sections when importing ELF information for easier checking later. 2. Keeping a reference to the section each relocation is from in order to get the list_head for the other relocations in that section. 3. Finding jump tables by following relocations to .rodata sections, rather than always referencing a single global .rodata section. The patch has been tested without data sections enabled and no differences in the resulting orc unwind information were seen. Note that as objtool adds terminators to end of each .text section the unwind information generated between a function+data sections build and a normal build aren't directly comparable. Manual inspection suggests that objtool is now generating the correct information, or at least making more of an effort to do so than it did previously. Signed-off-by: Allan Xavier <allan.x.xavier@oracle.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/099bdc375195c490dda04db777ee0b95d566ded1.1536325914.git.jpoimboe@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| arch/x86 | ||
| Documentation | ||
| .gitignore | ||
| arch.h | ||
| Build | ||
| builtin-check.c | ||
| builtin-orc.c | ||
| builtin.h | ||
| cfi.h | ||
| check.c | ||
| check.h | ||
| elf.c | ||
| elf.h | ||
| Makefile | ||
| objtool.c | ||
| orc.h | ||
| orc_dump.c | ||
| orc_gen.c | ||
| special.c | ||
| special.h | ||
| sync-check.sh | ||
| warn.h | ||