bc3703f21c
Using perf probe and libdw on kernel modules failed to find CFI data for symbols. The CFI data is stored in the .eh_frame section. The elfutils libdw is not able to extract the CFI data correctly, because the .eh_frame section requires "non-simple" relocations for kernel modules. The suggestion is to avoid these "non-simple" relocations by emitting the CFI data in the .debug_frame section. Let gcc emit respective directives by specifying the -fno-asynchronous-unwind-tables option. Using the .debug_frame section for CFI data, the .eh_frame section becomes unused and, thus, discard it for kernel and modules builds The vDSO requires the .eh_frame section and, hence, emit the CFI data in both, the .eh_frame and .debug_frame sections. See also discussion on elfutils/libdw bugzilla: https://sourceware.org/bugzilla/show_bug.cgi?id=22452 Suggested-by: Mark Wielaard <mark@klomp.org> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> |
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| Documentation | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.