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 163A31099B31 for ; Fri, 20 Mar 2026 18:04:50 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3DDD06B00CB; Fri, 20 Mar 2026 14:04:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3B5AD6B00CD; Fri, 20 Mar 2026 14:04:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2F21A6B00CE; Fri, 20 Mar 2026 14:04:50 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 18F1C6B00CB for ; Fri, 20 Mar 2026 14:04:50 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id B080D8B3AA for ; Fri, 20 Mar 2026 18:04:49 +0000 (UTC) X-FDA: 84567217098.18.B823FD0 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf15.hostedemail.com (Postfix) with ESMTP id 13915A0009 for ; Fri, 20 Mar 2026 18:04:47 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=QZ27rco1; spf=pass (imf15.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1774029888; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=lcQ0Sdq7MubbYaFxKqat7D7t1mE9+R5njCQKtCJ9D7I=; b=A+cnqw+UkY/sFnZBV1eSysU64TEgVvIyfIdTe0VLzw0NFtZZ6LzfndrL6PuhrQL8Pw0epr Wzzn5E6yXuMq+qUTii7MDAXzCFlTY+sOixoc3iekfDAIGfY5f88HToyx0gl6KJSSEWzxwh DJDUhIZ1gES8/oZaeHHI0ytvMVHkPB0= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=QZ27rco1; spf=pass (imf15.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1774029888; a=rsa-sha256; cv=none; b=5/UBSpO6g6bqSIG/oYigsh7wlGM7zXmaCSpzz7M5rTTJaiwcushaBguibY+1JWfk2MmjlO 4wmWicx0VveNXT7PwnmpJBZytNoYavL8a68UuXEwxfaWwq54mooEpgAmRPBZZwUqN/t+7O BmLaqe+ejbR1qF9mz5K6lsQJ+Rk9PxA= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 557AC60128; Fri, 20 Mar 2026 18:04:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D72E3C4CEF7; Fri, 20 Mar 2026 18:04:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774029887; bh=unEPL0G7kl0V7ExcXjxu9/JvZIzmQqH2o3lcKsyYewA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=QZ27rco17AvaGnAfGjFv9fbjrnbNb/BfO9dekg+xvlPU72urVZEkIzQpheARdN7oX Vs+NgmZp+tgmAcl/lUCr2UacLZ4Wxpf7npLq9DnOZT3HVnH5Yk4s4isbLmGzDB4MvF oKCYhNOBcuUByFR8bTJ6KnUKKU5lIxVvKIpQfayYigwTI55RVHFL5ZQ4weHd7bGSqd SygD3bA0+6GCLc0tbuV2U5dpwx1KjI2k0/7rKvD9CqKVfCZCWfWGU5abrkU1SRTj2u 4RkQ5sTSvE/IAINSi62Vr5lR00XN1qvOb+/BEVRBRspH02p8UXpvsau70MqGNd3rOq T8IxDYaCzldog== Date: Fri, 20 Mar 2026 18:04:40 +0000 From: "Lorenzo Stoakes (Oracle)" To: Zi Yan Cc: Andrew Morton , David Hildenbrand , Hugh Dickins , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Matthew Wilcox , Bas van Dijk , Eero Kelly , Andrew Battat , Adam Bratschi-Kaye , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v3] selftests/mm: add folio_split() and filemap_get_entry() race test Message-ID: References: <20260319190409.294523-1-ziy@nvidia.com> <6b087c27-a5d5-4f49-81e6-1204209b0c89@lucifer.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 13915A0009 X-Stat-Signature: ryhpmpyco4h893t7ztubcwch3i4tm145 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1774029887-88738 X-HE-Meta: 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 AadJ1LVj rR/Rywu+DLhUy1XoTOWzCA/NXImpjM9X6/2MmGuY/Sxonf+O/2XYrX643qbITIy87iMe24diHU3jWleeR/RMBpg1RXiAUzaG3OeryCEMsIP0vmU+cesytNmdKkcpwRFcGdL/j5IFnLTTZGBag9o5ddDnBicum3FopBnQi8Ja6UqEeO0jGT4GXUp1epu0aOu++ZW706qx9O0vWTQrMeirhpIdwaG6B2SCx2Et/fAhhhLYnhX18PJkcQgRsAoosZojPdknKNyzC+woyg7fnPxpS2EAH8I9UqjkOQcw56KU8PMGEXdPuWQgnBQWMeRzrMr79eTj0joxmA0sTexg6sun9YbuKMxyNzvVI+A7zHZvxC9qeb7XWzO4s8n/Q8B+IsGv97OKZ8dkheUkladIjhhSqmusyqz8xKaigozZm Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Mar 20, 2026 at 01:58:18PM -0400, Zi Yan wrote: > On 20 Mar 2026, at 13:53, Lorenzo Stoakes (Oracle) wrote: > > > (-cc old email) > > > > On Thu, Mar 19, 2026 at 03:04:08PM -0400, Zi Yan wrote: > >> The added folio_split_race_test is a modified C port of the race condition > >> test from [1]. The test creates shmem huge pages, where the main thread > >> punches holes in the shmem to cause folio_split() in the kernel and > >> a set of 16 threads reads the shmem to cause filemap_get_entry() in the > >> kernel. filemap_get_entry() reads the folio and xarray split by > >> folio_split() locklessly. The original test[2] is written in rust and uses > >> memfd (shmem backed). This C port uses shmem directly and use a single > >> process. > >> > >> Note: the initial rust to C conversion is done by Cursor. > >> > >> Link: https://lore.kernel.org/all/CAKNNEtw5_kZomhkugedKMPOG-sxs5Q5OLumWJdiWXv+C9Yct0w@mail.gmail.com/ [1] > >> Link: https://github.com/dfinity/thp-madv-remove-test [2] > >> Signed-off-by: Bas van Dijk > >> Signed-off-by: Adam Bratschi-Kaye > >> Signed-off-by: Zi Yan > > > > No .gitignore entry? :) > > > > (Just saw it flag up locally in git status) > > > > Linus says don't remove, but he doesn't say don't add :P > > I did not know about that. The fixup is below. Thank you for pointing it out. To be clear I'm referencing this re: the .gitignore _removals_ ;) https://lore.kernel.org/linux-mm/CAHk-=wiHK5_oBUdUiNAaevmN9f-ORe+QBqbRefAZaw-RbgEn3w@mail.gmail.com/ Thanks! :) > > From bd164a7090c0e8b6e3013502c64c161214e38714 Mon Sep 17 00:00:00 2001 > From: Zi Yan > Date: Fri, 20 Mar 2026 13:56:04 -0400 > Subject: [PATCH] git: add generated binary into gitignore > > Signed-off-by: Zi Yan > --- > tools/testing/selftests/mm/.gitignore | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/tools/testing/selftests/mm/.gitignore b/tools/testing/selftests/mm/.gitignore > index 83ad9454dd9d1..b0c30c5ee9e30 100644 > --- a/tools/testing/selftests/mm/.gitignore > +++ b/tools/testing/selftests/mm/.gitignore > @@ -61,3 +61,4 @@ guard-regions > merge > prctl_thp_disable > rmap > +folio_split_race_test > -- > 2.51.0 > > > > Best Regards, > Yan, Zi Cheers, Lorenzo