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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E1BAC30658 for ; Tue, 2 Jul 2024 17:36:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AF1ED6B009A; Tue, 2 Jul 2024 13:36:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AA1C76B009D; Tue, 2 Jul 2024 13:36:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 969276B009E; Tue, 2 Jul 2024 13:36:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 77F2F6B009A for ; Tue, 2 Jul 2024 13:36:32 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id F41C0120381 for ; Tue, 2 Jul 2024 17:36:31 +0000 (UTC) X-FDA: 82295516982.27.C525BD5 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf21.hostedemail.com (Postfix) with ESMTP id 391731C001C for ; Tue, 2 Jul 2024 17:36:30 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=k3oZhDx0; spf=pass (imf21.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719941767; 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:in-reply-to:references:references:dkim-signature; bh=tpL8HnKDjit/mjSIs4vuOOBBBplxkg2dw0Dy0YXhM8Q=; b=orLINIjN/4525GvSQ0EX7e70WWrwU7+2lBtyc6FgTj1BUz3pxIodMJ29LO+4TgPU4pXUJ9 iY7dhtHv1faCfX9i4Ic3fmu06Nvad3j7n2UUElW8p2bKwVlYbDDSpxS/MCiV6Ojft/XZ54 r0eUiUhJ1rehiAD5hbnMzBXQ47nIycU= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719941767; a=rsa-sha256; cv=none; b=UEDmp8Z4k68ZLWyjSfMEgzWlxM1K5lb3d2lYTGcUk9lBO6CLJMn0VJXA+jvR4FkHQEskrE jDZt6Qa8O5bDLictl9chX9LxtrIzVUOyk0VpIsHRtIPOHUuFlrpBi9P7fBdxe4p9iowdR9 EUubIcrjQetijW0vP5eZ3dVkMnnzTqA= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=k3oZhDx0; spf=pass (imf21.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 3E60761F13; Tue, 2 Jul 2024 17:36:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B2C5C4AF07; Tue, 2 Jul 2024 17:36:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1719941788; bh=65o+r9rQ6vTVCIzE0lvjV6bS9U8lgvQYQqtZ4G1YjFc=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=k3oZhDx0pnSiJK+UGXpf9eaXUQACBeaTkmorP8aGEpdT2dxDQ0ow+LA5xyQ2dfMzm nP6J8KwYvhs699+SoC7gJlOhCwAj+7dS0XHBKZa0aiKwtLNNth6kuGB5vUKp9/P5HQ BLtDzT6//k/wJ54lJej84TfKwUEFh4+cdBgFYOlk= Date: Tue, 2 Jul 2024 10:36:28 -0700 From: Andrew Morton To: Yosry Ahmed Cc: x86@kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , "Kirill A. Shutemov" , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RESEND PATCH v3 0/3] x86/mm: LAM fixups and cleanups Message-Id: <20240702103628.61879ef17b9b01305515c634@linux-foundation.org> In-Reply-To: <20240702132139.3332013-1-yosryahmed@google.com> References: <20240702132139.3332013-1-yosryahmed@google.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 391731C001C X-Stat-Signature: mms6ttcir8rsd91hfx8igrs4jagyanbu X-HE-Tag: 1719941790-187773 X-HE-Meta: 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 LGWpf4Jd lVjjNy7xlCikbPD03uDfedjfC6L9s8C9lhlwNO+TXPnLgXVTAwSoDJmS06gpFEMDKVPsOWY2zKLyRBxJeA9VcvOUkRl2magwYL8H2CCTW+hJGj/WEqYWlx6JnQQfdltu2BiAyz28CI8xTyeDiEzi93Wpvuv9lPQavfVcu6o5KU3AKlihiJv28+jPsiANMByP1b7xBUjUbH2ouLY+wQLUoV/7McK6RIC38xO9Kj1Rp38xSvCcRs4Ya0/SDtl9U1/MdTPEq 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: On Tue, 2 Jul 2024 13:21:36 +0000 Yosry Ahmed wrote: > This series has fixups and cleanups for LAM. Most importantly, patch 1 > fixes a sycnhronization issue that may cause crashes of userspace > applications. This is a resend of v3, rebased on top of v6.10-rc6. "Crashes of userspace applications" is bad. Yet the patchset has been floating about for four months. It's unclear (to me) how serious this is. Can you please explain how common this is, what the userspace application needs to do to trigger this, etc?