8c2500228b
[ Upstream commit cc879ab3ce39bc39f9b1d238b283f43a5f6f957d ]
thread_change_pc() uses CPU local data, so must be protected from
swapping CPUs while it is reading the breakpoint struct.
The error is more noticeable after 1e60f3564bad ("powerpc/watchpoints:
Track perf single step directly on the breakpoint"), which added an
unconditional __this_cpu_read() call in thread_change_pc(). However the
existing __this_cpu_read() that runs if a breakpoint does need to be
re-inserted has the same issue.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230829063457.54157-2-bgray@linux.ibm.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.