From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E236B46AEF0; Fri, 27 Feb 2026 20:09:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772222965; cv=none; b=T/u3N3vLr9yUTEoXJl6XCQfQwwu6uXeBPk4qeUNW2Mui+53GnJamIqSAPYJzRI/XV77UQKbgR8rPXys5CbaKqzv6rOtn1riBg0rXmP+dWoubHovELxj61Bhi3Ani52OQu3TKETnIguoMvEDyxUOIyp2UTY8i2iOV7QJHA4mpi3Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772222965; c=relaxed/simple; bh=oTLLv1/LtvCwIvkJbROBPO/znHjTWfNn5494fkK85gk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XQIUeaEd+o113uQepUh/6VvbryBj1stVmx5oJesDPVA0TAda7YSXVVjN7yE4fBRsynH6Hwb8+UCNKT3dXXYxl0Yj1olZpXwTJ8ZcYI7XtaFuXjNWep/PLJOAev1pVdMWcaNcXKpWHHaMbzxEdjQLME+PWNvNZZyckBJAWxwLax0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TykYjpWv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TykYjpWv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E80D2C19423; Fri, 27 Feb 2026 20:09:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772222964; bh=oTLLv1/LtvCwIvkJbROBPO/znHjTWfNn5494fkK85gk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TykYjpWvgGwljpM6p2COuJBm6vVZY9Djvp9ZNM6zX/Mg+sBmes0wCnbQ4WeSfbmW/ SV+IDNBtumzcZhC3ElSbyAiv475EkpQUkxeCLhsWULdxAHfGnT0H335AmzCjAN+dQj QRAOmuBYMH+Ynj0dVRD7vPT/l9+4APLtjm8nWyekU8kueRKpx8XbFw5ajrTVTYHSCI fPG3LX2/4RfCF7sYKFaOg85sIPFkNtlXfBAxGEQ4tDcYAx7xhGzd19vCY9jvvC0Ulp O7aQ9sT3wfiLxfn9cUcpLrszMNdsrZRZprFMOD9AkXLMBxMByussndPeKhWeTlHo/m zYXuh1oeZiM/A== From: "David Hildenbrand (Arm)" To: linux-kernel@vger.kernel.org Cc: "linux-mm @ kvack . org" , "David Hildenbrand (Arm)" , Andrew Morton , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , David Rientjes , Shakeel Butt , "Matthew Wilcox (Oracle)" , Alice Ryhl , Madhavan Srinivasan , Michael Ellerman , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Jarkko Sakkinen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Greg Kroah-Hartman , =?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= , Todd Kjos , Christian Brauner , Carlos Llamas , Ian Abbott , H Hartley Sweeten , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , David Airlie , Simona Vetter , Jason Gunthorpe , Leon Romanovsky , Dimitri Sivanich , Arnd Bergmann , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Peter Zijlstra , Arnaldo Carvalho de Melo , Namhyung Kim , Andy Lutomirski , Vincenzo Frascino , Eric Dumazet , Neal Cardwell , "David S. Miller" , David Ahern , Jakub Kicinski , Paolo Abeni , Miguel Ojeda , linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-sgx@vger.kernel.org, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-rdma@vger.kernel.org, bpf@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, rust-for-linux@vger.kernel.org, x86@kernel.org Subject: [PATCH v1 01/16] mm/madvise: drop range checks in madvise_free_single_vma() Date: Fri, 27 Feb 2026 21:08:32 +0100 Message-ID: <20260227200848.114019-2-david@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260227200848.114019-1-david@kernel.org> References: <20260227200848.114019-1-david@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit madvise_vma_behavior()-> madvise_dontneed_free()->madvise_free_single_vma() is only called from madvise_walk_vmas() (a) After try_vma_read_lock() confirmed that the whole range falls into a single VMA (see is_vma_lock_sufficient()). (b) After adjusting the range to the VMA in the loop afterwards. madvise_dontneed_free() might drop the MM lock when handling userfaultfd, but it properly looks up the VMA again to adjust the range. So in madvise_free_single_vma(), the given range should always fall into a single VMA and should also span at least one page. Let's drop the error checks. The code now matches what we do in madvise_dontneed_single_vma(), where we call zap_vma_range_batched() that documents: "The range must fit into one VMA.". Although that function still adjusts that range, we'll change that soon. Signed-off-by: David Hildenbrand (Arm) --- mm/madvise.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index c0370d9b4e23..efc04334a000 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -799,9 +799,10 @@ static int madvise_free_single_vma(struct madvise_behavior *madv_behavior) { struct mm_struct *mm = madv_behavior->mm; struct vm_area_struct *vma = madv_behavior->vma; - unsigned long start_addr = madv_behavior->range.start; - unsigned long end_addr = madv_behavior->range.end; - struct mmu_notifier_range range; + struct mmu_notifier_range range = { + .start = madv_behavior->range.start, + .end = madv_behavior->range.end, + }; struct mmu_gather *tlb = madv_behavior->tlb; struct mm_walk_ops walk_ops = { .pmd_entry = madvise_free_pte_range, @@ -811,12 +812,6 @@ static int madvise_free_single_vma(struct madvise_behavior *madv_behavior) if (!vma_is_anonymous(vma)) return -EINVAL; - range.start = max(vma->vm_start, start_addr); - if (range.start >= vma->vm_end) - return -EINVAL; - range.end = min(vma->vm_end, end_addr); - if (range.end <= vma->vm_start) - return -EINVAL; mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, range.start, range.end); -- 2.43.0