From: Michael Ellerman <mpe@xxxxxxxxxxxxxx> commit abf110f3e1cea40f5ea15e85f5d67c39c14568a7 upstream. For PowerVM migration we want to be able to call setup_rfi_flush() again after we've migrated the partition. To support that we need to check that we're not trying to allocate the fallback flush area after memblock has gone away (i.e., boot-time only). Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Mauricio Faria de Oliveira <mauricfo@xxxxxxxxxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/include/asm/setup.h | 2 +- arch/powerpc/kernel/setup_64.c | 6 +++++- 2 files changed, 6 insertions(+), 2 deletions(-) --- a/arch/powerpc/include/asm/setup.h +++ b/arch/powerpc/include/asm/setup.h @@ -36,7 +36,7 @@ enum l1d_flush_type { L1D_FLUSH_MTTRIG = 0x8, }; -void __init setup_rfi_flush(enum l1d_flush_type, bool enable); +void setup_rfi_flush(enum l1d_flush_type, bool enable); void do_rfi_flush_fixups(enum l1d_flush_type types); #endif /* !__ASSEMBLY__ */ --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -887,6 +887,10 @@ static void init_fallback_flush(void) u64 l1d_size, limit; int cpu; + /* Only allocate the fallback flush area once (at boot time). */ + if (l1d_flush_fallback_area) + return; + l1d_size = ppc64_caches.dsize; limit = min(safe_stack_limit(), ppc64_rma_size); @@ -904,7 +908,7 @@ static void init_fallback_flush(void) } } -void __init setup_rfi_flush(enum l1d_flush_type types, bool enable) +void setup_rfi_flush(enum l1d_flush_type types, bool enable) { if (types & L1D_FLUSH_FALLBACK) { pr_info("rfi-flush: Using fallback displacement flush\n");