mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-01-17 02:15:57 +00:00
Yonghong Song
5bd36da1e3
bpf: Support private stack for struct_ops progs
For struct_ops progs, whether a particular prog uses private stack depends on prog->aux->priv_stack_requested setting before actual insn-level verification for that prog. One particular implementation is to piggyback on struct_ops->check_member(). The next patch has an example for this. The struct_ops->check_member() sets prog->aux->priv_stack_requested to be true which enables private stack usage. The struct_ops prog follows the same rule as kprobe/tracing progs after function bpf_enable_priv_stack(). For example, even a struct_ops prog requests private stack, it could still use normal kernel stack if the stack size is small (< 64 bytes). Similar to tracing progs, nested same cpu same prog run will be skipped. A field (recursion_detected()) is added to bpf_prog_aux structure. If bpf_prog->aux->recursion_detected is implemented by the struct_ops subsystem and nested same cpu/prog happens, the function will be triggered to report an error, collect related info, etc. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20241112163933.2224962-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.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 reStructuredText 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.
Description
Languages
C
97.5%
Assembly
1%
Shell
0.6%
Python
0.3%
Makefile
0.3%