From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8EA64CCD1AB for ; Tue, 21 Oct 2025 19:46:02 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vBIHv-0008Vl-Kw; Tue, 21 Oct 2025 15:44:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vBIHt-0008VJ-TT for qemu-devel@nongnu.org; Tue, 21 Oct 2025 15:44:53 -0400 Received: from mail-ot1-x336.google.com ([2607:f8b0:4864:20::336]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1vBIHs-0006Cj-45 for qemu-devel@nongnu.org; Tue, 21 Oct 2025 15:44:53 -0400 Received: by mail-ot1-x336.google.com with SMTP id 46e09a7af769-7c27e5ca2beso1617669a34.3 for ; Tue, 21 Oct 2025 12:44:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1761075890; x=1761680690; darn=nongnu.org; h=content-transfer-encoding:in-reply-to:content-language:from :references:to:subject:user-agent:mime-version:date:message-id:from :to:cc:subject:date:message-id:reply-to; bh=jaRudyjBUXlwGlNpgWwa4/6HkWfm7wxdXyApdf6ZJ+A=; b=a6IlFzp9kTHbslA1lxb1WhBJqC61RAD6gRVGvfIvK0Z9QgcwI9er+8pulY7qcQJPNH c5JyXtKZ4qIdOgshCsARpmxJOUqcVpkFJc0Xm6irHyF1ECxdPZ092TfF5VrbbrBpgAJy kzO4O6gxwYXBqNX1hlVE48Ja3ati0hxkE9xJjip/zesFBv/1jJ3D021pczeJIKhNl0ql bj06YUcfMS+rKMRKgp0HNI8g8Af35nPWUUOOfXEHWSTvRuIO5BcjiwGU8+CGipgzQpK2 IL028anKLB8MomxkEiDFq027NbVVD6TfpzBZP7Rm0Z/7Y0A8fIMBEsT9mxTiI34lS9Ia 1w6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761075890; x=1761680690; h=content-transfer-encoding:in-reply-to:content-language:from :references:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=jaRudyjBUXlwGlNpgWwa4/6HkWfm7wxdXyApdf6ZJ+A=; b=e7/OCcS1f0a7MFghMZMvChuUNqQqq5xcXBLFFbopUjzVkOKyJx3E9hyoI5eFJdJHVP A/qrYWjtd090Bi1WFICWs+zZQeo/UF2UQ7cFCbLeDgme2oAgkwJ7ZiB8YG+jVEUbRdye sL1voziuqEtTFVV1WJ5yRg4KF2EBdTzKIN6knU9mqY/L/umEg+AKrtz9ASqJ6MUfDO2D 9dY7krYZ6arl93unGtYz01sSl7oCAdXPzJDJShl/tcLlN8HIEM3f8y1tr/Tpygu4laJU G9oB+lwlY5vYgJDtsfDmzu44Q+UcHACLBUHcGVrYLh3b2H1RJ+LOSHhtm3Kq+b0VMnKm /Omg== X-Gm-Message-State: AOJu0Yyyfx4zv9hrEU41nqIyj1j0V7WkyvSoV0CDZe39l9uSHHwfbpIt sUFnJLbOA1LyHCkdWpzDnNknUwNaVv9ua7AdjBStTcd3saFOzrQ288l/+kCO4i8J8idYgE5Fqhg LYxzy X-Gm-Gg: ASbGnctxXKhGio+B21/0PAhOvySEznuRtmd+ABvQFM5GgsNK8J+iJQ4wcaJniPxWdYG /fTS3DZ0LkJ1rt6zNBsW7Cz6ATfyTVdKgT5A+gNyivfX90ChsCk8Q7l2SLueBhJdqJapVc1I3Yl hJEEh+dalvMjaawpbDdiwdEuiKLJJjHTtpoUnZ/MtYgEq8ciqLiIPV0LkX0o9h0TZzyv7Islk01 htXij8fg2gellq2KJiPhyvBMdYueepH1/lKKNdof/YKWDcvclGSo8hyN+ieL1oeVbI5vzGPKK3n 1dmrBOFhZzqBJevQTFLfSmlwQi4eAbi2GuFEpv6qUHMiK8641bIElnPUqOoDd4NrfJRoFBykXFe aT+B3DpcWYjzqnyXFM2Bh/PNIEBkDDZCTt3ToC5ykDMdFBm6rdtZBZWTjjTPv9G0uZBrJABIJpl 1fUVa17ifvn8OED3heXGKNpt2ZlhPDQ7VphrqS9tIQqf8j59aDtl95aW1k4fQ= X-Google-Smtp-Source: AGHT+IHkeAunGQ5R5s+e0aa+n50w98lXa9N7XlZmbZ6meLu0nKtYz1dzGiH0ufqoG8U3jAoiu/fnVw== X-Received: by 2002:a05:6830:719e:b0:7b7:6e45:7f2c with SMTP id 46e09a7af769-7c27cc84ebcmr8631422a34.30.1761075889938; Tue, 21 Oct 2025 12:44:49 -0700 (PDT) Received: from [10.128.41.227] (c-174-170-192-123.hsd1.tx.comcast.net. [174.170.192.123]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7c2887b8588sm3907182a34.11.2025.10.21.12.44.49 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 21 Oct 2025 12:44:49 -0700 (PDT) Message-ID: <68c8d609-37a4-4369-ac5e-1542612371c6@linaro.org> Date: Tue, 21 Oct 2025 14:44:45 -0500 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] linux-user: fix mremap unmapping adjacent region To: qemu-devel@nongnu.org References: <20251011200337.30258-1-mlugg@mlugg.co.uk> <20251011200337.30258-2-mlugg@mlugg.co.uk> From: Richard Henderson Content-Language: en-US In-Reply-To: <20251011200337.30258-2-mlugg@mlugg.co.uk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::336; envelope-from=richard.henderson@linaro.org; helo=mail-ot1-x336.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 10/11/25 15:03, Matthew Lugg wrote: > This typo meant that calls to `mremap` which shrink a mapping by some N > bytes would, when the virtual address space was pre-reserved (e.g. > 32-bit guest on 64-bit host), unmap the N bytes following the *original* > mapping. > > Signed-off-by: Matthew Lugg > --- > linux-user/mmap.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/linux-user/mmap.c b/linux-user/mmap.c > index 847092a28a..ec8392b35b 100644 > --- a/linux-user/mmap.c > +++ b/linux-user/mmap.c > @@ -1164,7 +1164,8 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, > errno = ENOMEM; > host_addr = MAP_FAILED; > } else if (reserved_va && old_size > new_size) { > - mmap_reserve_or_unmap(old_addr + old_size, > + /* Re-reserve pages we just shrunk out of the mapping */ > + mmap_reserve_or_unmap(old_addr + new_size, > old_size - new_size); > } > } Reviewed-by: Richard Henderson r~