mainlining shenanigans
532319b9c4
When unwinding the stack from a stack overflow, we are likely to start from a stack push instruction, given that this is the most common way to grow the stack for compiler emitted code. This push instruction rarely appears anywhere else than at offset 0x0 of the function, and if it doesn't, the compiler tends to split up the unwind annotations, given that the stack frame layout is apparently not the same throughout the function. This means that, in the general case, if the frame's PC points at the first instruction covered by a certain unwind entry, there is no way the stack frame that the unwind entry describes could have been created yet, and so we are still on the stack frame of the caller in that case. So treat this as a special case, and return with the new PC taken from the frame's LR, without applying the unwind transformations to the virtual register set. This permits us to unwind the call stack on stack overflow when the overflow was caused by a stack push on function entry. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Keith Packard <keithpac@amazon.com> Tested-by: Marc Zyngier <maz@kernel.org> Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M |
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| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| 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 | ||
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.
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.