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 473CCC79FA1 for ; Tue, 8 Sep 2026 11:29:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 537B96B008C; Tue, 8 Sep 2026 07:29:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4E8BC6B009F; Tue, 8 Sep 2026 07:29:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3D7E06B00A0; Tue, 8 Sep 2026 07:29:17 -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 0E57B6B008C for ; Tue, 8 Sep 2026 07:29:17 -0400 (EDT) Received: from smtpin03.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 9CF33A4DAC for ; Tue, 8 Sep 2026 11:29:16 +0000 (UTC) X-FDA: 85190373912.03.26B30CA Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf24.hostedemail.com (Postfix) with ESMTP id E02F1180002 for ; Tue, 8 Sep 2026 11:29:14 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=UaGEuylv; spf=pass (imf24.hostedemail.com: domain of ljs@kernel.org designates 172.234.252.31 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=1788866955; 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=wrZchMHbuIO6XXck0lzWb4MFVBIJqfPNOjZp2CkiLAo=; b=17nViULAFS+jJNTP0zmWBA0tmx24Dc+yOK5Kog4jKJuUSZmpHY8MlkNLohURZemnGLHDoO 3gMb9Vw8qkSjeAs8zuLKlnm590K2AExC9Wg10Wg1/O7uJL/+3hkmSJeMBKUXjbag8S49Gl 4UHuLHXpJ3i7p9MRzLyNrHL9YKNv1DE= ARC-Authentication-Results: i=1; imf24.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=UaGEuylv; spf=pass (imf24.hostedemail.com: domain of ljs@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1788866955; b=rwtL5xNUZ1jrPcW6HM8VeIeZB51texyJ3X1Hsgx373F6iM/AKkKZcotADDO672BrIyLCyK RiuDoMMA+G1Qk6XIbmBrIPmKv3eSSweWaP2ERctrK98J/C76J+wjbkv1Lpro6hvcQl+gEN IjTXRQtD+y0J68tWDCaKDkdJR46ubmI= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 0DDBA41328; Tue, 8 Sep 2026 11:29:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DD8561F00A3A; Tue, 8 Sep 2026 11:28:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788866953; bh=wrZchMHbuIO6XXck0lzWb4MFVBIJqfPNOjZp2CkiLAo=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=UaGEuylvnKTadsfjaS7bvwU33xN2v3VvG9wjjwlcHZzqg4jRyqMpEEdO03+MvqeIM 0cduj0er10VqGiGsJx7yjqifKpSllSZ3vK2y8omgzwmD0GHCZufWGZlTXVUWUiJ1V9 ryqufjLkVU0NIOGHntM/W5uaFdDur34HOl0mDF/iX8gW88SDJFV9ZGxssqTmrANwpQ ynMdPQCgyGQbU6JnCqU5u6mlf0Svv7YVwvZzUogSUfvbxLoYO7+FDhTi6mBmpO9DWp jokGL7RYOK/KgBIS1bsW+dwWJav2y/DtDFT7YQL4WN6vyefxcqOuYZ/U9v7ZU8r1QK 2OBX8O/r781rA== Date: Tue, 8 Sep 2026 12:28:51 +0100 From: "Lorenzo Stoakes (ARM)" To: Suren Baghdasaryan Cc: Andrew Morton , David Hildenbrand , Zi Yan , Baolin Wang , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Kiryl Shutsemau , Guo Ren , Brian Cain , Geert Uytterhoeven , Dinh Nguyen , Simon Schuster , Jonas Bonn , Stefan Kristiansson , Stafford Horne , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Russell King , Vineet Gupta , Michal Simek , Chris Zankel , Max Filippov , Will Deacon , "Aneesh Kumar K.V" , Nick Piggin , Peter Zijlstra , "David S. Miller" , Andreas Larsson , Richard Henderson , Matt Turner , Magnus Lindholm , Catalin Marinas , Mark Rutland , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Madhavan Srinivasan , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Richard Weinberger , Anton Ivanov , Johannes Berg , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Arnd Bergmann , Vlastimil Babka , Mike Rapoport , Michal Hocko , Jason Gunthorpe , John Hubbard , Peter Xu , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-sh@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-snps-arc@lists.infradead.org, linux-arch@vger.kernel.org, sparclinux@vger.kernel.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, Hugh Dickins , Qi Zheng Subject: Re: [PATCH 05/12] mm: enable MMU_GATHER_RCU_TABLE_FREE for arc, microblaze, xtensa Message-ID: References: <20260901-rcu-pagetable-freeing-v1-0-5456a81c8212@kernel.org> <20260901-rcu-pagetable-freeing-v1-5-5456a81c8212@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: E02F1180002 X-Stat-Signature: t8cm85gpn3c6j6qoe7bmn7nfjnhwdneg X-Rspam-User: X-HE-Tag: 1788866954-573911 X-HE-Meta: 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 1JPH0mb4 2yKr692i21vHcBR2IFmDxusrraHN+2olHEoQalDQAa+LRDnq1TqZI74Ef4XFZqSR+Sk5+xeIWN4D4QlAt/ancrAwFTUFjnNRJkXMUCKj9DZRpFGAUN5w+xvQMQBdjOI1txhNQXSMU0zbLmxMRQDPur4jcl7ZkXHasmX8RakJTLSbQRo2zgS+2mtWTUEGwDRQ0p/kebDjeXZKc8kKoLm7vHtJ2hkjpA1zJDeLz70KND4HH49XovmhViXwXehFNn7LhlqlvyMqemY7Bx9ObubeaN1eWB2LGYlpGQaBsA24nmRbTYwfUQIH5lsOgoPQpn/Lav2eUtFlO7648PHxwKp1iOVIUQX9FdBNJYB5w1tfLnFkrlNOfwZp2wGhmVhkCiXlwJqGWex8WaqvMB5dAJz9cTrQXzS2UWi8dGoTCk8wB3s7sGgA= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Sep 07, 2026 at 02:07:37PM -0700, Suren Baghdasaryan wrote: > On Tue, Sep 1, 2026 at 4:06 AM Lorenzo Stoakes (ARM) wrote: > > > > Each of these architectures directly free page tables without routing these > > changes through tlb_remove_ptdesc(). > > > > The use of tlb_remove_ptdesc() is required for > > CONFIG_MMU_GATHER_RCU_TABLE_FREE to correctly free page tables under RCU, > > so simply update these architectures to use these functions. > > > > Since none of the architectures share page tables or do anything unusual, > > nothing complicated is required here. > > > > Therefore this is simply a mechanical change - convert __pud_free_tlb(), > > __pmd_free_tlb() and __pte_free_tlb() to use tlb_remove_ptdesc() as > > required. > > > > At the point this is in place, all mmu_gather page table freeing is > > performed under RCU, and thus MMU_GATHER_RCU_TABLE_FREE is selected for > > each architecture. > > > > This forms part of an overall effort to switch every architecture to this > > mode. > > > > Signed-off-by: Lorenzo Stoakes (ARM) > > --- > > arch/arc/Kconfig | 1 + > > arch/arc/include/asm/pgalloc.h | 6 +++--- > > arch/microblaze/Kconfig | 1 + > > arch/microblaze/include/asm/pgalloc.h | 2 +- > > arch/xtensa/Kconfig | 1 + > > arch/xtensa/include/asm/tlb.h | 2 +- > > 6 files changed, 8 insertions(+), 5 deletions(-) > > > > diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig > > index 2ed7186c81c5..7a7542b61823 100644 > > --- a/arch/arc/Kconfig > > +++ b/arch/arc/Kconfig > > @@ -47,6 +47,7 @@ config ARC > > select HAVE_SYSCALL_TRACEPOINTS > > select IRQ_DOMAIN > > select LOCK_MM_AND_FIND_VMA > > + select MMU_GATHER_RCU_TABLE_FREE > > select MODULES_USE_ELF_RELA > > select OF > > select OF_EARLY_FLATTREE > > diff --git a/arch/arc/include/asm/pgalloc.h b/arch/arc/include/asm/pgalloc.h > > index dfae070fe8d5..9b6c37f92e97 100644 > > --- a/arch/arc/include/asm/pgalloc.h > > +++ b/arch/arc/include/asm/pgalloc.h > > @@ -72,7 +72,7 @@ static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp) > > set_p4d(p4dp, __p4d((unsigned long)pudp)); > > } > > > > -#define __pud_free_tlb(tlb, pmd, addr) pud_free((tlb)->mm, pmd) > > +#define __pud_free_tlb(tlb, pmd, addr) tlb_remove_ptdesc((tlb), virt_to_ptdesc(pmd)) > > > > #endif > > > > @@ -83,10 +83,10 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp) > > set_pud(pudp, __pud((unsigned long)pmdp)); > > } > > > > -#define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd) > > +#define __pmd_free_tlb(tlb, pmd, addr) tlb_remove_ptdesc((tlb), virt_to_ptdesc(pmd)) > > > > #endif > > > > -#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte) > > +#define __pte_free_tlb(tlb, pte, addr) tlb_remove_ptdesc((tlb), page_ptdesc(pte)) > > > > #endif /* _ASM_ARC_PGALLOC_H */ > > diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig > > index 484ebb3baedf..af7e821e96c1 100644 > > --- a/arch/microblaze/Kconfig > > +++ b/arch/microblaze/Kconfig > > @@ -41,6 +41,7 @@ config MICROBLAZE > > select PCI_SYSCALL if PCI > > select CPU_NO_EFFICIENT_FFS > > select MMU_GATHER_NO_RANGE > > + select MMU_GATHER_RCU_TABLE_FREE > > select SPARSE_IRQ > > select ZONE_DMA > > select TRACE_IRQFLAGS_SUPPORT > > diff --git a/arch/microblaze/include/asm/pgalloc.h b/arch/microblaze/include/asm/pgalloc.h > > index 084a8a0dc239..ffee6a009219 100644 > > --- a/arch/microblaze/include/asm/pgalloc.h > > +++ b/arch/microblaze/include/asm/pgalloc.h > > @@ -25,7 +25,7 @@ extern void __bad_pte(pmd_t *pmd); > > > > extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm); > > > > -#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, (pte)) > > +#define __pte_free_tlb(tlb, pte, addr) tlb_remove_ptdesc((tlb), page_ptdesc(pte)) > > > > #define pmd_populate(mm, pmd, pte) \ > > (pmd_val(*(pmd)) = (unsigned long)page_address(pte)) > > diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig > > index f2f9cd9cde50..33c4caee30e2 100644 > > --- a/arch/xtensa/Kconfig > > +++ b/arch/xtensa/Kconfig > > @@ -55,6 +55,7 @@ config XTENSA > > select HAVE_VIRT_CPU_ACCOUNTING_GEN > > select IRQ_DOMAIN > > select LOCK_MM_AND_FIND_VMA > > + select MMU_GATHER_RCU_TABLE_FREE if MMU > > And MMU is required because NOMMU does not perform mmu_gather > operations, same as in the previous patch? If so, maybe make a note of > it in the changelog? Right yup. Will update! > > > select MODULES_USE_ELF_RELA > > select PERF_USE_VMALLOC > > select TRACE_IRQFLAGS_SUPPORT > > diff --git a/arch/xtensa/include/asm/tlb.h b/arch/xtensa/include/asm/tlb.h > > index 8c3ceb427018..6fb7b78154f6 100644 > > --- a/arch/xtensa/include/asm/tlb.h > > +++ b/arch/xtensa/include/asm/tlb.h > > @@ -16,7 +16,7 @@ > > > > #include > > > > -#define __pte_free_tlb(tlb, pte, address) pte_free((tlb)->mm, pte) > > +#define __pte_free_tlb(tlb, pte, address) tlb_remove_ptdesc((tlb), page_ptdesc(pte)) > > > > void check_tlb_sanity(void); > > > > > > -- > > 2.55.0 > > -- Cheers, Lorenzo