From 177ba7c647f37bc3f31667192059ee794347d79d Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 29 Apr 2016 23:26:10 +1000 Subject: [PATCH] powerpc/mm/radix: Limit paca allocation in radix On return from RTAS we access the paca variables and we have 64 bit disabled. This requires us to limit paca in 32 bit range. Fix this by setting ppc64_rma_size to first_memblock_size/1G range. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/mm/pgtable-radix.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index 0472f8aa40e1..04ec9760380d 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -351,7 +351,25 @@ void radix__early_init_mmu_secondary(void) void radix__setup_initial_memory_limit(phys_addr_t first_memblock_base, phys_addr_t first_memblock_size) { - /* Finally limit subsequent allocations */ + /* We don't currently support the first MEMBLOCK not mapping 0 + * physical on those processors + */ + BUG_ON(first_memblock_base != 0); + /* + * We limit the allocation that depend on ppc64_rma_size + * to first_memblock_size. We also clamp it to 1GB to + * avoid some funky things such as RTAS bugs. + * + * On radix config we really don't have a limitation + * on real mode access. But keeping it as above works + * well enough. + */ + ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000); + /* + * Finally limit subsequent allocations. We really don't want + * to limit the memblock allocations to rma_size. FIXME!! should + * we even limit at all ? + */ memblock_set_current_limit(first_memblock_base + first_memblock_size); } -- 2.20.1