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 C9EB5C4345F for ; Thu, 2 May 2024 07:30:49 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 33AEF6B0087; Thu, 2 May 2024 03:30:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2C3BE6B0089; Thu, 2 May 2024 03:30:49 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 163BB6B008A; Thu, 2 May 2024 03:30:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id EC2016B0087 for ; Thu, 2 May 2024 03:30:48 -0400 (EDT) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 99EFD1A0713 for ; Thu, 2 May 2024 07:30:48 +0000 (UTC) X-FDA: 82072633776.07.64B1792 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf04.hostedemail.com (Postfix) with ESMTP id D075D4000B for ; Thu, 2 May 2024 07:30:46 +0000 (UTC) Authentication-Results: imf04.hostedemail.com; dkim=none; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1714635047; 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; bh=YuO/PS70T1YPaLW+Pp2YJw4QksqFA7aBJ3nphbVjYiY=; b=pu/sBGWX/gghLhUXPTo/aOtx4DhKvj3w9whrhbOQmIiK7X8XOGvDi+8/ddjdGrQgNIesVO cA1BqujKJPKI4IpnSIw4Fz93f9GU0JCUlm/2/71uCczVno9lUc1TGi9paNyraLHd5A5MAd e+fkpWXn/GHVTtbUMFS+fwJ+yGbeTT4= ARC-Authentication-Results: i=1; imf04.hostedemail.com; dkim=none; spf=pass (imf04.hostedemail.com: domain of ryan.roberts@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=ryan.roberts@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1714635047; a=rsa-sha256; cv=none; b=i2Q98oNB/Prbr0e/RJwaSMOdjs+qLXbhJVtkWfwztR4/B0Z+e7vPsiGL2F14GgFvS0hOmH wWAQXqgej1OrsLPfNGhwiskponemQp38b/6mBSvfO+vOxEQohX8SadT5MTZN8qN7dv/2LT ebftZs/a892icGex5cPu7m4IA+85nP8= Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 688C32F4; Thu, 2 May 2024 00:31:11 -0700 (PDT) Received: from [10.57.65.146] (unknown [10.57.65.146]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 187673F71E; Thu, 2 May 2024 00:30:44 -0700 (PDT) Message-ID: Date: Thu, 2 May 2024 08:30:42 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1] mm/debug_vm_pgtable: Test pmd_leaf() behavior with pmd_mkinvalid() Content-Language: en-GB To: Anshuman Khandual , Andrew Morton , Catalin Marinas Cc: linux-mm@kvack.org References: <20240501144439.1389048-1-ryan.roberts@arm.com> From: Ryan Roberts In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: qrnxtysepi3n7jd91mm7gftn63yats31 X-Rspam-User: X-Rspamd-Queue-Id: D075D4000B X-Rspamd-Server: rspam05 X-HE-Tag: 1714635046-116487 X-HE-Meta: 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 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 02/05/2024 03:43, Anshuman Khandual wrote: > Hello Ryan, > > On 5/1/24 20:14, Ryan Roberts wrote: >> An invalidated pmd should still cause pmd_leaf() to return true. Let's >> test for that to ensure all arches remain consistent. > > This test definitely makes sense. > >> >> Signed-off-by: Ryan Roberts >> --- >> >> Hi Andrew, >> >> This applies on top of v6.9-rc5. It came out of a discussion with Catalin around >> the pmd_mkinvalid() bug (the fix for which I just posted). I've run the new test >> on both arm64 and x86_64. > > Right, works on arm64. > >> >> Thanks, >> Ryan >> >> mm/debug_vm_pgtable.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c >> index 65c19025da3d..57e9cb0820ab 100644 >> --- a/mm/debug_vm_pgtable.c >> +++ b/mm/debug_vm_pgtable.c >> @@ -981,6 +981,7 @@ static void __init pmd_thp_tests(struct pgtable_debug_args *args) >> #ifndef __HAVE_ARCH_PMDP_INVALIDATE >> WARN_ON(!pmd_trans_huge(pmd_mkinvalid(pmd_mkhuge(pmd)))); >> WARN_ON(!pmd_present(pmd_mkinvalid(pmd_mkhuge(pmd)))); >> + WARN_ON(!pmd_leaf(pmd_mkinvalid(pmd_mkhuge(pmd)))); >> #endif /* __HAVE_ARCH_PMDP_INVALIDATE */ >> } > > Should not we update descriptions in Documentation/mm/arch_pgtable_helpers.rst > asserting that pmd_mkinvalid() also preserves pmd_leaf() ? Thanks for the review! We don't document that pmd_mkinvalid() preserves pmd_present() and pmd_trans_huge() so I wasn't sure how much detail was appropriate in that document - its pretty light at the moment. If you think this is valuable (and isn't clear enough from the test) then I can add something. But as you say in the other patch, it would then start conflicting with that. I'd prefer to just put this in as-is to avoid the mess.