df78d3f614
The "Power Architecture 64-Bit ELF V2 ABI" says in section 2.3.2.3: [...] There are several rules that must be adhered to in order to ensure reliable and consistent call chain backtracing: * Before a function calls any other function, it shall establish its own stack frame, whose size shall be a multiple of 16 bytes. – In instances where a function’s prologue creates a stack frame, the back-chain word of the stack frame shall be updated atomically with the value of the stack pointer (r1) when a back chain is implemented. (This must be supported as default by all ELF V2 ABI-compliant environments.) [...] – The function shall save the link register that contains its return address in the LR save doubleword of its caller’s stack frame before calling another function. To me this sounds like the equivalent of HAVE_RELIABLE_STACKTRACE. This patch may be unneccessarily limited to ppc64le, but OTOH the only user of this flag so far is livepatching, which is only implemented on PPCs with 64-LE, a.k.a. ELF ABI v2. Feel free to add other ppc variants, but so far only ppc64le got tested. This change also implements save_stack_trace_tsk_reliable() for ppc64le that checks for the above conditions, where possible. Signed-off-by: Torsten Duwe <duwe@suse.de> Signed-off-by: Nicolai Stange <nstange@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
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.