From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 721183E40F2; Tue, 8 Sep 2026 20:12:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788898348; cv=none; b=Fe48BrUA67coUPjfvfCfHTk2k7gU7Ik/ah8Fp8ee0DsaNmvTiKTj6ixjgl9JYaKnuPclfhi3IwBF/T5BXjdZ1iojZWue7rbvrfZ7BgENgMH1gylrDNtXTnDBWxD3DkZ4X8ISQQqMugG0hQ65Gvw4ktohLUQT7Wq8I2+T8GrZXJE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788898348; c=relaxed/simple; bh=yDTjgG6ZNulCil8lAdq/Sm+oS00ngLRTCfWCLIVxqmc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=TmW0I7ftqQsIjlqHkJhh7DacUpTbS0KNOgLzOmNNI2xNGQPT+Z5xgu84NRWJAa/Evea7C3Fr+GAbIPM8Vqa3CAhel/J9wvQaYhryIU4uaX6JI+nyT5Kbg2K+8SlHyJ1Mm+71vGYgtmRDzkygOYjrDeEI3rGQkhQT7i3mZwcQQeI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SWzMB6ct; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SWzMB6ct" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 366701F00A3A; Tue, 8 Sep 2026 20:11:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788898347; bh=IFwYdR7MdQIJkwtfLhXuGSNYO6+D1BHAE+s6WKkSbT0=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=SWzMB6ctH7t/MOHNYI3kwBx7MduIk36u1vcWmcbZO26FPbQ6LHV+ZWUSunKZRGZze D9qhEgZQgsGW1c8l3Lm8HdEJhOSR9gFBGvda16hgajVgACwDxGiLvYFhAidd3Gpz8h XJxJly0i9SW+h8Ma9aKCk7QLtDYFMoLr3s7VBDV34gKIdAnLxjQwI3KV+nRijGa7Oc FLK3CcvWOdUyAMNyWyXvC5ugj/JgZJZMBdfBCIDPMmT625PVXOPcpPQrdzhNGu8ril Q7XMtJjzAOyHi6EKrbCH8f9QDo1CDyhzHCkTank3MhnS+1WOEWITxPjYb9Lo4g98NU uBB28fIPgF7fA== From: "Lorenzo Stoakes (ARM)" Date: Tue, 08 Sep 2026 21:01:25 +0100 Subject: [PATCH 21/39] uprobes: remove VM_IO, set VM_MIXEDMAP for mapped kernel pages Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-21-dacf19cce22b@kernel.org> References: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org> In-Reply-To: <20260908-b4-mmap-prepare-vma-flag-sanify-v1-0-dacf19cce22b@kernel.org> To: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Jann Horn , Pedro Falcato , David Hildenbrand , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Greg Kroah-Hartman , Dennis Dalessandro , Jason Gunthorpe , Leon Romanovsky , Paul Moore , Stephen Smalley , Jaroslav Kysela , Takashi Iwai , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Kumar Kartikeya Dwivedi , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Doug Gilbert , "James E.J. Bottomley" , "Martin K. Petersen" , Jaya Kumar , Simona Vetter , Helge Deller , Sebastian Reichel , John Hubbard , Peter Xu , Masami Hiramatsu , Oleg Nesterov , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Rik van Riel , Harry Yoo , Juri Lelli , Vincent Guittot , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Arnd Bergmann , Muchun Song , Oscar Salvador , "Matthew Wilcox (Oracle)" , Jan Kara , Marc Zyngier , Oliver Upton , Catalin Marinas , Madhavan Srinivasan , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , "David S. Miller" , Andreas Larsson , Alexander Viro , Christian Brauner , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Youngjun Park , Johannes Weiner , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Xu Xin , Chengming Zhou , Michal Hocko , Miklos Szeredi Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-usb@vger.kernel.org, linux-rdma@vger.kernel.org, selinux@vger.kernel.org, linux-sound@vger.kernel.org, bpf@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, fuse-devel@lists.linux.dev, "Lorenzo Stoakes (ARM)" X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=2032; i=ljs@kernel.org; h=from:subject:message-id; bh=yDTjgG6ZNulCil8lAdq/Sm+oS00ngLRTCfWCLIVxqmc=; b=owGbwMvMwCV2fu7ZrsZH9SKMp9WSGLIWZG5eu2fSr9vLF9Tt/2A6uebt/Ok8E85ftD1aveAq5 9uiWPMPDh2lLAxiXAyyYoosz7+I7w8SCZvXecHfDWYOKxPIEAYuTgGYSGcywz9NjwAp/U/RMWkR VR83sU/gKWX0f/hqqbXuX4GUtq+ZrowM/+wZ3y6R3ma/adn3tbq2/WLXv31Z/lvQcF9RTIVzgKY RAyMA X-Developer-Key: i=ljs@kernel.org; a=openpgp; fpr=E7F417BF5214569E89D04F46CF9DCD8A81E27F14 These are not MMIO pages so VMA_IO_BIT is an inappropriate flag to set. Instead, set them VMA_MIXEDMAP_BIT as they are kernel mappings and this is the appropriate flag to set for those. This provides the semantics required - no VMA merging is permitted, but does not prevent GUP. However this has no meaningful impact as these are refcounted and thus can be GUPed. A previous commit already prevented __mm_populate() from being invoked on XOL areas which prevents so that is no longer required. Both VMAs set a VMA name, so always_dump_vma() returns true before vma_dump_size() reaches its VMA_IO_BIT check, and thus there is no change in core dump behaviour. Change this for both the core xol_add_vma() function and the x86-specific get_uprobe_trampoline() function. Signed-off-by: Lorenzo Stoakes (ARM) --- arch/x86/kernel/uprobes.c | 2 +- kernel/events/uprobes.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index 65a2de82ecd2..0f60c0d076b6 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -715,7 +715,7 @@ static struct vm_area_struct *get_uprobe_trampoline(struct mm_struct *mm, unsign *new_mapping = true; return _install_special_mapping(mm, vaddr, PAGE_SIZE, - VM_READ|VM_EXEC|VM_MAYEXEC|VM_MAYREAD|VM_IO, + VM_READ|VM_EXEC|VM_MAYEXEC|VM_MAYREAD|VM_MIXEDMAP, &tramp_mapping); } diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 7709ea882477..b89cc5cee002 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -1726,8 +1726,8 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area) } vma = _install_special_mapping(mm, area->vaddr, PAGE_SIZE, - VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO| - VM_SEALED_SYSMAP, + VM_EXEC|VM_MAYEXEC|VM_DONTCOPY| + VM_MIXEDMAP|VM_SEALED_SYSMAP, &xol_mapping); if (IS_ERR(vma)) { ret = PTR_ERR(vma); -- 2.55.0