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 77152646 for ; Fri, 15 Nov 2024 05:18:01 +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=1731647881; cv=none; b=upBlcFyYk5/Y8L/qaN/ve1/Rt7/hM4tIBqH9rToL5GUS0mEt9VHpLDltlNuDCyF5N99vCeQDqsSxHtF2uGt/so1n+Lqd/o93SppZ0HpTudogcKCb6g1H0AWPm8FA8K0o4lTI/cVNlv24ze1Uw1MHKWAUh9QwyMxJ2j/DmP72d+o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731647881; c=relaxed/simple; bh=Ehk4DKAlNTYCDMCa+Ww5BRZ91YOtiCmTpS6hA99VBx0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eqyUhohpEpwiwLsDa/HPe/V161pn/L5PvT8U+2p5zsFgChq0uGpI1gaALZwLDrxrFWYEMpE7MzXUpnmMXBQaIq7P9nRrIw0/B7mRFcN+RQufsl8+u7tES+kZ5mXB4y5Ez+yRUP2Cu6aEbnNvu/eIhFRSifuaTZecwXByUedFoAg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=h/u8Wnox; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="h/u8Wnox" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 84B0CC4CECF; Fri, 15 Nov 2024 05:18:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1731647881; bh=Ehk4DKAlNTYCDMCa+Ww5BRZ91YOtiCmTpS6hA99VBx0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=h/u8WnoxdI9XUbGKKEPv/U/7DnOMufmGhzbSIg8cooEuFD6sRJ9mVW0AgKofDzJtq oJxfkrutSEh/d875Lh03JoGfM2YWHdScMzagDPIRAmd3bULtlyAADBaqyaDhYvU1KM 2zqPlsPhfWRUVdYv0VJ0cNcBSkZeIU49Xk8tC3PA= Date: Fri, 15 Nov 2024 06:17:57 +0100 From: Greg KH To: David Hildenbrand Cc: Vlastimil Babka , stable@vger.kernel.org, Peter Xu , linux-mm@kvack.org, Yuanzheng Song Subject: Re: [PATCH stable 5.15] mm/memory: add non-anonymous page check in the copy_present_page() Message-ID: <2024111547-tying-selected-6a5e@gregkh> References: <20241113163118.54834-2-vbabka@suse.cz> <99a77c9a-68ca-4445-bcbf-4681ca20a482@redhat.com> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <99a77c9a-68ca-4445-bcbf-4681ca20a482@redhat.com> On Wed, Nov 13, 2024 at 05:45:43PM +0100, David Hildenbrand wrote: > On 13.11.24 17:31, Vlastimil Babka wrote: > > From: Yuanzheng Song > > > > The vma->anon_vma of the child process may be NULL because > > the entire vma does not contain anonymous pages. In this > > case, a BUG will occur when the copy_present_page() passes > > a copy of a non-anonymous page of that vma to the > > page_add_new_anon_rmap() to set up new anonymous rmap. > > > > ------------[ cut here ]------------ > > kernel BUG at mm/rmap.c:1052! > > Internal error: Oops - BUG: 0 [#1] SMP > > Modules linked in: > > CPU: 4 PID: 4652 Comm: test Not tainted 5.15.75 #1 > > Hardware name: linux,dummy-virt (DT) > > pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > > pc : __page_set_anon_rmap+0xc0/0xe8 > > lr : __page_set_anon_rmap+0xc0/0xe8 > > sp : ffff80000e773860 > > x29: ffff80000e773860 x28: fffffc13cf006ec0 x27: ffff04f3ccd68000 > > x26: ffff04f3c5c33248 x25: 0000000010100073 x24: ffff04f3c53c0a80 > > x23: 0000000020000000 x22: 0000000000000001 x21: 0000000020000000 > > x20: fffffc13cf006ec0 x19: 0000000000000000 x18: 0000000000000000 > > x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 > > x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 > > x11: 0000000000000000 x10: 0000000000000000 x9 : ffffdddc5581377c > > x8 : 0000000000000000 x7 : 0000000000000011 x6 : ffff2717a8433000 > > x5 : ffff80000e773810 x4 : ffffdddc55400000 x3 : 0000000000000000 > > x2 : ffffdddc56b20000 x1 : ffff04f3c9a48040 x0 : 0000000000000000 > > Call trace: > > __page_set_anon_rmap+0xc0/0xe8 > > page_add_new_anon_rmap+0x13c/0x200 > > copy_pte_range+0x6b8/0x1018 > > copy_page_range+0x3a8/0x5e0 > > dup_mmap+0x3a0/0x6e8 > > dup_mm+0x78/0x140 > > copy_process+0x1528/0x1b08 > > kernel_clone+0xac/0x610 > > __do_sys_clone+0x78/0xb0 > > __arm64_sys_clone+0x30/0x40 > > invoke_syscall+0x68/0x170 > > el0_svc_common.constprop.0+0x80/0x250 > > do_el0_svc+0x48/0xb8 > > el0_svc+0x48/0x1a8 > > el0t_64_sync_handler+0xb0/0xb8 > > el0t_64_sync+0x1a0/0x1a4 > > Code: 97f899f4 f9400273 17ffffeb 97f899f1 (d4210000) > > ---[ end trace dc65e5edd0f362fa ]--- > > Kernel panic - not syncing: Oops - BUG: Fatal exception > > SMP: stopping secondary CPUs > > Kernel Offset: 0x5ddc4d400000 from 0xffff800008000000 > > PHYS_OFFSET: 0xfffffb0c80000000 > > CPU features: 0x44000cf1,00000806 > > Memory Limit: none > > ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]--- > > > > This problem has been fixed by the commit > > ("mm/rmap: split page_dup_rmap() into page_dup_file_rmap() > > and page_try_dup_anon_rmap()"), but still exists in the > > linux-5.15.y branch. > > > > This patch is not applicable to this version because > > of the large version differences. Therefore, fix it by > > adding non-anonymous page check in the copy_present_page(). > > > > Cc: stable@vger.kernel.org > > Fixes: 70e806e4e645 ("mm: Do early cow for pinned pages during fork() for ptes") > > Signed-off-by: Yuanzheng Song > > Signed-off-by: Vlastimil Babka > > --- > > Hi, this was posted in [1] but seems stable@ was not actually included > > in the recipients. > > The 5.10 version [2] was applied as 935a8b62021 but 5.15 is missing. > > > > [1] https://lore.kernel.org/all/20221028075244.3112566-1-songyuanzheng@huawei.com/T/#u > > [2] https://lore.kernel.org/all/20221028030705.2840539-1-songyuanzheng@huawei.com/ > > > > > > mm/memory.c | 11 +++++++++++ > > 1 file changed, 11 insertions(+) > > > > diff --git a/mm/memory.c b/mm/memory.c > > index 6d058973a97e..4785aecca9a8 100644 > > --- a/mm/memory.c > > +++ b/mm/memory.c > > @@ -903,6 +903,17 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma > > if (likely(!page_needs_cow_for_dma(src_vma, page))) > > return 1; > > + /* > > + * The vma->anon_vma of the child process may be NULL > > + * because the entire vma does not contain anonymous pages. > > + * A BUG will occur when the copy_present_page() passes > > + * a copy of a non-anonymous page of that vma to the > > + * page_add_new_anon_rmap() to set up new anonymous rmap. > > + * Return 1 if the page is not an anonymous page. > > + */ > > + if (!PageAnon(page)) > > + return 1; > > + > > new_page = *prealloc; > > if (!new_page) > > return -EAGAIN; > > Reviewed-by: David Hildenbrand Now queued up, thanks. greg k-h