mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-05 18:41:58 +09:00
668350eba9
commit 45cb47c628dfbd1994c619f3eac271a780602826 upstream.
Refactor the register restoration sequence in the ftrace_common_return
function to clearly distinguish between the logic of normal returns and
direct call returns in function tracing scenarios. The logic is as
follows:
1. In the case of a normal return, the execution flow returns to the
traced function, and ftrace must ensure that the register data is
consistent with the state when the function was entered.
ra = parent return address; t0 = traced function return address.
2. In the case of a direct call return, the execution flow jumps to the
custom trampoline function, and ftrace must ensure that the register
data is consistent with the state when ftrace was entered.
ra = traced function return address; t0 = parent return address.
Cc: stable@vger.kernel.org
Fixes: 9cdc3b6a29 ("LoongArch: ftrace: Add direct call support")
Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.