4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Hari Bathini <hbath...@linux.ibm.com> [ Upstream commit 8950329c4a64c6d3ca0bc34711a1afbd9ce05657 ] Memory reservation for crashkernel could fail if there are holes around kdump kernel offset (128M). Fail gracefully in such cases and print an error message. Signed-off-by: Hari Bathini <hbath...@linux.ibm.com> Tested-by: David Gibson <dgib...@redhat.com> Reviewed-by: Dave Young <dyo...@redhat.com> Signed-off-by: Michael Ellerman <m...@ellerman.id.au> Signed-off-by: Sasha Levin <alexander.le...@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/powerpc/kernel/machine_kexec.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/arch/powerpc/kernel/machine_kexec.c +++ b/arch/powerpc/kernel/machine_kexec.c @@ -186,7 +186,12 @@ void __init reserve_crashkernel(void) (unsigned long)(crashk_res.start >> 20), (unsigned long)(memblock_phys_mem_size() >> 20)); - memblock_reserve(crashk_res.start, crash_size); + if (!memblock_is_region_memory(crashk_res.start, crash_size) || + memblock_reserve(crashk_res.start, crash_size)) { + pr_err("Failed to reserve memory for crashkernel!\n"); + crashk_res.start = crashk_res.end = 0; + return; + } } int overlaps_crashkernel(unsigned long start, unsigned long size)