6041186a32
When a module option, or core kernel argument, toggles a static-key it requires jump labels to be initialized early. While x86, PowerPC, and ARM64 arrange for jump_label_init() to be called before parse_args(), ARM does not. Kernel command line: rdinit=/sbin/init page_alloc.shuffle=1 panic=-1 console=ttyAMA0,115200 page_alloc.shuffle=1 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at ./include/linux/jump_label.h:303 page_alloc_shuffle+0x12c/0x1ac static_key_enable(): static key 'page_alloc_shuffle_key+0x0/0x4' used before call to jump_label_init() Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-rc4-next-20190410-00003-g3367c36ce744 #1 Hardware name: ARM Integrator/CP (Device Tree) [<c0011c68>] (unwind_backtrace) from [<c000ec48>] (show_stack+0x10/0x18) [<c000ec48>] (show_stack) from [<c07e9710>] (dump_stack+0x18/0x24) [<c07e9710>] (dump_stack) from [<c001bb1c>] (__warn+0xe0/0x108) [<c001bb1c>] (__warn) from [<c001bb88>] (warn_slowpath_fmt+0x44/0x6c) [<c001bb88>] (warn_slowpath_fmt) from [<c0b0c4a8>] (page_alloc_shuffle+0x12c/0x1ac) [<c0b0c4a8>] (page_alloc_shuffle) from [<c0b0c550>] (shuffle_store+0x28/0x48) [<c0b0c550>] (shuffle_store) from [<c003e6a0>] (parse_args+0x1f4/0x350) [<c003e6a0>] (parse_args) from [<c0ac3c00>] (start_kernel+0x1c0/0x488) Move the fallback call to jump_label_init() to occur before parse_args(). The redundant calls to jump_label_init() in other archs are left intact in case they have static key toggling use cases that are even earlier than option parsing. Link: http://lkml.kernel.org/r/155544804466.1032396.13418949511615676665.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Guenter Roeck <groeck@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Russell King <rmk@armlinux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| 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.
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.