From: Nicholas Piggin <npiggin@xxxxxxxxx> commit a1ee28117077c3bf24e5ab6324c835eaab629c45 upstream. This can be hit by an HPT guest running on an HPT host and bring down the host, so it's quite important to fix. Fixes: 7290f3b3d3e6 ("powerpc/64s/powernv: machine check dump SLB contents") Cc: stable@xxxxxxxxxxxxxxx # v5.4+ Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx> Acked-by: Mahesh Salgaonkar <mahesh@xxxxxxxxxxxxx> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20201128070728.825934-2-npiggin@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/powerpc/platforms/powernv/setup.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/arch/powerpc/platforms/powernv/setup.c +++ b/arch/powerpc/platforms/powernv/setup.c @@ -186,11 +186,16 @@ static void __init pnv_init(void) add_preferred_console("hvc", 0, NULL); if (!radix_enabled()) { + size_t size = sizeof(struct slb_entry) * mmu_slb_size; int i; /* Allocate per cpu area to save old slb contents during MCE */ - for_each_possible_cpu(i) - paca_ptrs[i]->mce_faulty_slbs = memblock_alloc_node(mmu_slb_size, __alignof__(*paca_ptrs[i]->mce_faulty_slbs), cpu_to_node(i)); + for_each_possible_cpu(i) { + paca_ptrs[i]->mce_faulty_slbs = + memblock_alloc_node(size, + __alignof__(struct slb_entry), + cpu_to_node(i)); + } } }