From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x242.google.com (mail-pf0-x242.google.com [IPv6:2607:f8b0:400e:c00::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3yVp6Z1lMDzDrK5 for ; Mon, 6 Nov 2017 21:03:34 +1100 (AEDT) Received: by mail-pf0-x242.google.com with SMTP id i5so7367795pfe.6 for ; Mon, 06 Nov 2017 02:03:33 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Cc: Nicholas Piggin , "Aneesh Kumar K . V" , Florian Weimer Subject: [PATCH 1/5] powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation Date: Mon, 6 Nov 2017 21:03:11 +1100 Message-Id: <20171106100315.29720-2-npiggin@gmail.com> In-Reply-To: <20171106100315.29720-1-npiggin@gmail.com> References: <20171106100315.29720-1-npiggin@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , When allocating VA space with a hint that crosses 128TB, the SLB addr_limit variable is not expanded if addr is not > 128TB, but the slice allocation looks at task_size, which is 512TB. This results in slice_check_fit() incorrectly succeeding because the slice_count truncates off bit 128 of the requested mask, so the comparison to the available mask succeeds. Fix this by using mm->context.addr_limit instead of mm->task_size for testing allocation limits. This causes such allocations to fail. Cc: "Aneesh Kumar K.V" Fixes: f4ea6dcb08 ("powerpc/mm: Enable mappings above 128TB") Reported-by: Florian Weimer Signed-off-by: Nicholas Piggin --- arch/powerpc/mm/slice.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 45f6740dd407..567db541c0a1 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -96,7 +96,7 @@ static int slice_area_is_free(struct mm_struct *mm, unsigned long addr, { struct vm_area_struct *vma; - if ((mm->task_size - len) < addr) + if ((mm->context.addr_limit - len) < addr) return 0; vma = find_vma(mm, addr); return (!vma || (addr + len) <= vm_start_gap(vma)); @@ -133,7 +133,7 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret) if (!slice_low_has_vma(mm, i)) ret->low_slices |= 1u << i; - if (mm->task_size <= SLICE_LOW_TOP) + if (mm->context.addr_limit <= SLICE_LOW_TOP) return; for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.addr_limit); i++) @@ -446,19 +446,20 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, /* Sanity checks */ BUG_ON(mm->task_size == 0); + BUG_ON(mm->context.addr_limit == 0); VM_BUG_ON(radix_enabled()); slice_dbg("slice_get_unmapped_area(mm=%p, psize=%d...\n", mm, psize); slice_dbg(" addr=%lx, len=%lx, flags=%lx, topdown=%d\n", addr, len, flags, topdown); - if (len > mm->task_size) + if (len > mm->context.addr_limit) return -ENOMEM; if (len & ((1ul << pshift) - 1)) return -EINVAL; if (fixed && (addr & ((1ul << pshift) - 1))) return -EINVAL; - if (fixed && addr > (mm->task_size - len)) + if (fixed && addr > (mm->context.addr_limit - len)) return -ENOMEM; /* If hint, make sure it matches our alignment restrictions */ @@ -466,7 +467,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, addr = _ALIGN_UP(addr, 1ul << pshift); slice_dbg(" aligned addr=%lx\n", addr); /* Ignore hint if it's too large or overlaps a VMA */ - if (addr > mm->task_size - len || + if (addr > mm->context.addr_limit - len || !slice_area_is_free(mm, addr, len)) addr = 0; } -- 2.15.0