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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5CA44CCF9EF for ; Tue, 28 Oct 2025 09:17:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B25CE8E018E; Tue, 28 Oct 2025 05:17:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AFC428E018C; Tue, 28 Oct 2025 05:17:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9279A8E018E; Tue, 28 Oct 2025 05:17:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 73EEC8E0006 for ; Tue, 28 Oct 2025 05:17:23 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 3F21612A593 for ; Tue, 28 Oct 2025 09:17:23 +0000 (UTC) X-FDA: 84046969566.02.7C12D99 Received: from todd.t-8ch.de (todd.t-8ch.de [159.69.126.157]) by imf30.hostedemail.com (Postfix) with ESMTP id 85CB280007 for ; Tue, 28 Oct 2025 09:17:21 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=weissschuh.net header.s=mail header.b=n3Cna5cw; dmarc=pass (policy=quarantine) header.from=weissschuh.net; spf=pass (imf30.hostedemail.com: domain of linux@weissschuh.net designates 159.69.126.157 as permitted sender) smtp.mailfrom=linux@weissschuh.net ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1761643041; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:in-reply-to: references:dkim-signature; bh=noNlmxCJE3KO/lPWg5rcvAC/N6+hMXNKqLIKFsG5DTo=; b=Od1ctZ6O3SPsxmnQOrPAGYKeq67sNGiNccpEpHrLLrI4r+VFlVxW6tFzEfSnXj0GX5PwhG 6RPpE/otO5JSn8KNLocBHMg8GXKpMMeq7KI/qm+01gicrH4oCdvVPyMXyZfcTlLkrh0Yjc vTXWm+YHYK/mOgNRlc3MCaswbr70TFM= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1761643041; a=rsa-sha256; cv=none; b=aTQXw6810BsVgz5+7NtfJmuBwqtosdv8rp7KXV0ElilaFpmrl7WWS0Xx/ouhL8HiKdnc/M lXxWKjHcLcwn7UnOI5009nwaop4vmum7CP+oHBXKei7eJ27Vl9l0y+Pvj57hhzhpt818Px 75SC6li2oD74IFqJcFlI27i9zEJmqD0= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=weissschuh.net header.s=mail header.b=n3Cna5cw; dmarc=pass (policy=quarantine) header.from=weissschuh.net; spf=pass (imf30.hostedemail.com: domain of linux@weissschuh.net designates 159.69.126.157 as permitted sender) smtp.mailfrom=linux@weissschuh.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=weissschuh.net; s=mail; t=1761643037; bh=xB7h3ce2gbt35UPG3jOGIq2cIVnYk+vgnnNmKPQ3hUc=; h=From:Subject:Date:To:Cc:From; b=n3Cna5cwrHoFXFZwXsYyr7xr8U1JWDVfqk8mrpEf4PO2s+yHzfo9ae9GaHIoF8OAT pZxv9lkhfM75w4QdyKXmE+mYxFbn4uRlRg22lrILG3xbdF/DL60Hb0d1d53sXXv02R 62OfOdhoO6A1fBQUiI+iFw7EzH6AhO4EqQgAt/tg= From: =?utf-8?q?Thomas_Wei=C3=9Fschuh?= Subject: [PATCH 00/10] um: remove vDSO passthrough on 32bit x86 Date: Tue, 28 Oct 2025 10:15:35 +0100 Message-Id: <20251028-uml-remove-32bit-pseudo-vdso-v1-0-e930063eff5f@weissschuh.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-B4-Tracking: v=1; b=H4sIALeJAGkC/x3MQQ6CMBAF0KuQWTtJHQHRqxAWYL8wiVDSgcaEc Hcbl2/zDjJEhdGzOCgiqWlYMq6Xgl5Tv4xg9dkkTir3kIr3+cMRc0jgmwy68WrYfeDkLXAzOLl LiaaWmnKxRrz1++/b7jx/CUHeqW4AAAA= X-Change-ID: 20250925-uml-remove-32bit-pseudo-vdso-8b02724e8626 To: Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Kees Cook Cc: linux-um@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, =?utf-8?q?Thomas_Wei=C3=9Fschuh?= X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1761643036; l=1974; i=linux@weissschuh.net; s=20221212; h=from:subject:message-id; bh=xB7h3ce2gbt35UPG3jOGIq2cIVnYk+vgnnNmKPQ3hUc=; b=fy3Gznoqa4idS4vD+Qw7c736OSjfulXJWRQdumuwvFU5YCVJrhuicwaakAQoBCgYhdehVlJzU ntwkq3FfWbvCXZdNvbbkRNDKA4+YT8j8iaJXv5Yyc1gTYwqKH/G2rWl X-Developer-Key: i=linux@weissschuh.net; a=ed25519; pk=KcycQgFPX2wGR5azS7RhpBqedglOZVgRPfdFSPB1LNw= X-Rspam-User: X-Rspamd-Queue-Id: 85CB280007 X-Rspamd-Server: rspam02 X-Stat-Signature: nw4rmh3iyuxgdbdjq653k9r41actijng X-HE-Tag: 1761643041-285623 X-HE-Meta: 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 yOHOHvgt ZbxaWu3bAiNE6YExeaQArEqO3vItPEh6vSsq4mX8Z+z/wr6roj0PtfPrvWOyWWPZ4uz7kpEHWZcRMNXN9CPYNaCVH4A+6ykmsZOqJAMPQkme5Ud6i7n5UT4kKNUxfBWSn8rDdBMfpMbEWn6wVqPxc2F7JQU4B0ZOYg2gzVP0gN9Q1IXw30Yoo2+9xXDTeeLmvLq+HLp/qvP/dRypsnQjiU5FB2V7ZYF9rbUizGqkZjk7Laqbs2Mr/2BsC1A== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Inheriting the vDSO from the host is problematic. The values read from the time functions will not be correct for the UML kernel. Furthermore the start and end of the vDSO are not stable or detectable by userspace. Specifically the vDSO datapages start before AT_SYSINFO_EHDR and the vDSO itself is larger than a single page. This codepath is only used on 32bit x86 UML. In my testing with both 32bit and 64bit hosts the passthrough functionality has always been disabled anyways due to the checks against envp in scan_elf_aux(). Signed-off-by: Thomas Weißschuh --- Thomas Weißschuh (10): um: Split out default elf_aux_platform x86/um: Move ELF_PLATFORM fallback to x86-specific code um: Split out default elf_aux_hwcap x86/um: Do not inherit vDSO from host x86/um: Drop gate area handling um: Remove fixaddr_user_init() um: Remove redundant range check from __access_ok_vsyscall() um: Remove __access_ok_vsyscall() x86/um: Remove FIXADDR_USER_START and FIXADDR_USE_END um: Always set up AT_HWCAP and AT_PLATFORM arch/um/include/asm/page.h | 4 -- arch/um/include/asm/uaccess.h | 9 +--- arch/um/kernel/mem.c | 107 ------------------------------------------ arch/um/os-Linux/Makefile | 4 +- arch/um/os-Linux/elf_aux.c | 37 +++------------ arch/um/os-Linux/main.c | 4 -- arch/um/os-Linux/user_syms.c | 6 --- arch/x86/um/Kconfig | 4 -- arch/x86/um/Makefile | 5 +- arch/x86/um/asm/elf.h | 39 ++------------- arch/x86/um/elfcore.c | 78 ------------------------------ arch/x86/um/mem_32.c | 50 -------------------- 12 files changed, 15 insertions(+), 332 deletions(-) --- base-commit: 83e4187d1b952c36ffc2d01a2e532ad8a9e80a76 change-id: 20250925-uml-remove-32bit-pseudo-vdso-8b02724e8626 Best regards, -- Thomas Weißschuh