c4e3ff8b8b
commit 5bb60ea611db1e04814426ed4bd1c95d1487678e upstream.
Since the commit c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not
activate MMU before reading task struct") a vmap stack overflow
results in a hard lockup. This is because emergency_ctx is still
addressed with its virtual address allthough data MMU is not active
anymore at that time.
Fix it by using a physical address instead.
Fixes: c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ce30364fb7ccda489272af4a1612b6aa147e1d23.1637227521.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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.