1389f17937
arch_ftrace_get_regs is supposed to return a struct pt_regs pointer
only if the pt_regs structure contains all register contents, which
means it must have been populated when created via ftrace_regs_caller.
If it was populated via ftrace_caller the contents are not complete
(the psw mask part is missing), and therefore a NULL pointer needs be
returned.
The current code incorrectly always returns a struct pt_regs pointer.
Fix this by adding another pt_regs flag which indicates if the
contents are complete, and fix arch_ftrace_get_regs accordingly.
Fixes: 894979689d3a ("s390/ftrace: provide separate ftrace_caller/ftrace_regs_caller implementations")
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reported-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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.