| From a1ee28117077c3bf24e5ab6324c835eaab629c45 Mon Sep 17 00:00:00 2001 |
| From: Nicholas Piggin <npiggin@gmail.com> |
| Date: Sat, 28 Nov 2020 17:07:21 +1000 |
| Subject: powerpc/64s/powernv: Fix memory corruption when saving SLB entries on MCE |
| |
| From: Nicholas Piggin <npiggin@gmail.com> |
| |
| 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@vger.kernel.org # v5.4+ |
| Signed-off-by: Nicholas Piggin <npiggin@gmail.com> |
| Acked-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> |
| Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> |
| Link: https://lore.kernel.org/r/20201128070728.825934-2-npiggin@gmail.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| 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)); |
| + } |
| } |
| } |
| |
