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a3961f824c
Rebooting into a new kernel with kexec fails in trace_tlbie() which is
called from native_hpte_clear(). This happens if the running kernel
has CONFIG_LOCKDEP enabled. With lockdep enabled, the tracepoints
always execute few RCU checks regardless of whether tracing is on or
off. We are already in the last phase of kexec sequence in real mode
with HILE_BE set. At this point the RCU check ends up in
RCU_LOCKDEP_WARN and causes kexec to fail.
Fix this by not calling trace_tlbie() from native_hpte_clear().
mpe: It's not safe to call trace points at this point in the kexec
path, even if we could avoid the RCU checks/warnings. The only
solution is to not call them.
Fixes: 0428491cba ("powerpc/mm: Trace tlbie(l) instructions")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.