4bbbc9c4f3
[ Upstream commit 53c9d9240944088274aadbbbafc6138ca462db4f ] SWAPGS is used only for interrupts coming from user mode or for returning to user mode. So there is no reason to use the PARAVIRT framework, as it can easily be replaced by an ALTERNATIVE depending on X86_FEATURE_XENPV. There are several instances using the PV-aware SWAPGS macro in paths which are never executed in a Xen PV guest. Replace those with the plain swapgs instruction. For SWAPGS_UNSAFE_STACK the same applies. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210120135555.32594-5-jgross@suse.com Signed-off-by: Sasha Levin <sashal@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 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.