mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-11-10 20:48:12 +00:00
No description
- C 96.8%
- Assembly 0.9%
- Rust 0.7%
- Shell 0.6%
- Python 0.5%
- Other 0.3%
8094df1cf0
When analysing a stacktrace it can be useful to know whether an unwound PC has been rewritten by fgraph or kretprobes, as in some situations these may be suspect or be known to be unreliable. This patch adds flags to track when an unwind entry has recovered the PC from fgraph and/or kretprobes, and updates dump_backtrace() to log when this is the case. The flags recorded are: "F" - the PC was recovered from fgraph "K" - the PC was recovered from kretprobes These flags are recorded and logged in addition to the original source of the unwound PC. For example, with the ftrace_graph profiler enabled globally, and kretprobes installed on generic_handle_domain_irq() and do_interrupt_handler(), a backtrace triggered by magic-sysrq + L reports: | Call trace: | show_stack+0x20/0x40 (CF) | dump_stack_lvl+0x60/0x80 (F) | dump_stack+0x18/0x28 | nmi_cpu_backtrace+0xfc/0x140 | nmi_trigger_cpumask_backtrace+0x1c8/0x200 | arch_trigger_cpumask_backtrace+0x20/0x40 | sysrq_handle_showallcpus+0x24/0x38 (F) | __handle_sysrq+0xa8/0x1b0 (F) | handle_sysrq+0x38/0x50 (F) | pl011_int+0x460/0x5a8 (F) | __handle_irq_event_percpu+0x60/0x220 (F) | handle_irq_event+0x54/0xc0 (F) | handle_fasteoi_irq+0xa8/0x1d0 (F) | generic_handle_domain_irq+0x34/0x58 (F) | gic_handle_irq+0x54/0x140 (FK) | call_on_irq_stack+0x24/0x58 (F) | do_interrupt_handler+0x88/0xa0 | el1_interrupt+0x34/0x68 (FK) | el1h_64_irq_handler+0x18/0x28 | el1h_64_irq+0x64/0x68 | default_idle_call+0x34/0x180 | do_idle+0x204/0x268 | cpu_startup_entry+0x40/0x50 (F) | rest_init+0xe4/0xf0 | start_kernel+0x744/0x750 | __primary_switched+0x80/0x90 Note that as these flags are reported next to the recovered PC value, they appear on the callers of instrumented functions. For example gic_handle_irq() has a "K" marker because generic_handle_domain_irq() was instrumented with kretprobes and had its return address rewritten. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Puranjay Mohan <puranjay12@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Madhavan T. Venkataraman <madvenka@linux.microsoft.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20241017092538.1859841-9-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
History
|
|
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| 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 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.