powerpc/kexec: Fix kexec when using VMX optimised memcpy
commit b3f271e8 (powerpc: POWER7 optimised memcpy using VMX and enhanced prefetch) uses VMX when it is safe to do so (ie not in interrupt). It also looks at the task struct to decide if we have to save the current tasks' VMX state. kexec calls memcpy() at a point where the task struct may have been overwritten by the new kexec segments. If it has been overwritten then when memcpy -> enable_altivec looks up current->thread.regs->msr we get a cryptic oops or lockup. I also notice we aren't initialising thread_info->cpu, which means smp_processor_id is broken. Fix that too. Signed-off-by:Anton Blanchard <anton@samba.org> Cc: <stable@vger.kernel.org> # 3.6+ Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
parent
83d5e64b
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