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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 5FFE9CF31AD for ; Wed, 19 Nov 2025 11:38:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=1k6hiefpZNiDm3uqDBvrzYJ/HsNFRw0daGH2fKm6G6Y=; b=SC4CJjbtrbyhecokKQ8LU+1caK PNrFws+QiKNRZmpkV0kOAY9NK0f7Ye+nTZSmhsRzj1CtdhOP8zTQIkHPYR06pOPhfFMH1KsUqfKM5 BEgZvj0ex1nWGAL/b2bucImaovyCawGqv9fe5M8lEvY9rdim4Pacok2QLSyDotR0jGTjzBaeDdkeb Mb6KsD8rJazGugcW9XBayFMFDhoYdemARdJOoPLM2L54EFrC5yf1KWD45tUmMSVOCoFyyQ4lm/1gu HA8TY7o5/tzq8isaOXWqWIprj00ITcTehDeNisoolh4uDL+i/sQUs6ixcc4m+cdJfbgunkrGmIlON 5pZVtB8w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLgWX-000000032qQ-0YXW; Wed, 19 Nov 2025 11:38:57 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLgWV-000000032pk-1DWt for linux-um@lists.infradead.org; Wed, 19 Nov 2025 11:38:56 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id A9B6143B53; Wed, 19 Nov 2025 11:38:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 510B7C2BCB4; Wed, 19 Nov 2025 11:38:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763552334; bh=09EAP2XN+lRanTOPE2mYQg/imEyLIAMTytu/FERJ3KE=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=ZbpzBxMPlijcUIWVvcKZTNGa7zCAJwZY9chXx+w8GbRHAR+rI1lSfYrqXSSvSDYaE MePEVV4EjqdFYyQgiSidQHYaWwO7pQarT3TKZOtNh3sSfSwIQ6SflX1gDL9lMSxLny w06MV9gY5w5TZlc4+ewlulKiXr9osdtN3qFwbuQWIMM4miVH0RvJzhNpO1lxypNit0 eeE/heuKvBJlnAAv4sK4Mv4MYw7Xohrvhu7Amo4HOBaY8PCND2DXnAiONttsXskaMh 8/Bno4vIYUEF05KYxb1WyXsUI4O64niqkk/pUg+0oPMnWbdq0tM2VTdA0KoQ6gV8im c4sJ+iwsxJ/XQ== Message-ID: <9b55623a-4606-4610-a0fe-55b8cd6b95e7@kernel.org> Date: Wed, 19 Nov 2025 12:38:46 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 7/7] mm: enable PT_RECLAIM on all 64-bit architectures To: Qi Zheng , will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com, peterz@infradead.org, dev.jain@arm.com, akpm@linux-foundation.org, ioworker0@gmail.com, linmag7@gmail.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-um@lists.infradead.org, Qi Zheng References: From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251119_033855_361151_9945C274 X-CRM114-Status: GOOD ( 14.49 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On 19.11.25 08:31, Qi Zheng wrote: > From: Qi Zheng > > Now, the MMU_GATHER_RCU_TABLE_FREE is enabled on all 64-bit architectures, > so make PT_RECLAIM depend on 64BIT, thereby enabling PT_RECLAIM on all > 64-bit architectures. > > Signed-off-by: Qi Zheng > --- > arch/x86/Kconfig | 1 - > mm/Kconfig | 9 ++------- > 2 files changed, 2 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index eac2e86056902..96bff81fd4787 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -330,7 +330,6 @@ config X86 > select FUNCTION_ALIGNMENT_4B > imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI > select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE > - select ARCH_SUPPORTS_PT_RECLAIM if X86_64 > select ARCH_SUPPORTS_SCHED_SMT if SMP > select SCHED_SMT if SMP > select ARCH_SUPPORTS_SCHED_CLUSTER if SMP > diff --git a/mm/Kconfig b/mm/Kconfig > index d548976d0e0ad..94eec5c0cad96 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -1448,14 +1448,9 @@ config ARCH_HAS_USER_SHADOW_STACK > The architecture has hardware support for userspace shadow call > stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). > > -config ARCH_SUPPORTS_PT_RECLAIM > - def_bool n > - > config PT_RECLAIM > - bool "reclaim empty user page table pages" > - default y > - depends on ARCH_SUPPORTS_PT_RECLAIM && MMU && SMP > - select MMU_GATHER_RCU_TABLE_FREE > + def_bool y > + depends on 64BIT As discussed in the other thread, likely config PT_RECLAIM def_bool y depends on MMU_GATHER_RCU_TABLE_FREE && 64BIT Could be nice, and if possible even dropping the 64BIT limitation as well if there is no need to. -- Cheers David