9d38cd06c3
vsprintf is incorrect. Instead of adding the read memory barrier into vsprintf() which will cause a slight degradation to a commonly used function in the kernel just to solve a very unlikely race condition that can only happen at boot up, change the code from using a variable branch to a static_branch. Not only does this solve the race condition, it actually will improve the performance of vsprintf() by removing the conditional branch that is only needed at boot. -----BEGIN PGP SIGNATURE----- iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCWvwtURQccm9zdGVkdEBn b29kbWlzLm9yZwAKCRAp5XQQmuv6ql1NAP4g19xnu23+fPADOLWj8CShIGroIPvC vNkg8UMNW6qWyAEA32aPJyRAC/hqqEgYbBBUHFNVyqdwZ38os7gnqzfBRwQ= =Vw/o -----END PGP SIGNATURE----- Merge tag 'trace-v4.17-rc5-vsprintf' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull memory barrier for from Steven Rostedt: "The memory barrier usage in updating the random ptr hash for %p in vsprintf is incorrect. Instead of adding the read memory barrier into vsprintf() which will cause a slight degradation to a commonly used function in the kernel just to solve a very unlikely race condition that can only happen at boot up, change the code from using a variable branch to a static_branch. Not only does this solve the race condition, it actually will improve the performance of vsprintf() by removing the conditional branch that is only needed at boot" * tag 'trace-v4.17-rc5-vsprintf' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: vsprintf: Replace memory barrier with static_key for random_ptr_key update
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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.