From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 513A5606A31C for ; Thu, 12 Nov 2026 12:00:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=ei3FM4jR; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=mykMNeh5 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:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=wTN3UxTT/XXw7NH/F07ZSE1+SznsV7bVJZdXlw3Sm0E=; b=ei3FM4jRVeg5lbptuTo1pNz71N d+dVFq6rhlt6I4y5SxhFCLSiiNp9V3EsAASzsRJf/GQRHD/WlbQlGACTGdh4LKgo7OFebHaf0FmuR QJGlLjeaqQLsDUf68T/G+KhPHWs6vLrO+uar/UzBXpwh0u01KWJ9l8mVtyJTrzZ70nuTEcCNch6hC 6oDmBUgTAnJIJjcXyUA7mqj2MQDgEoNf9V2Ld2yy9Hy7A3jk30f9pLk+lpk+xH4jR1YMCNuKkrpGi hbUKyOucUADXWtoSErziZ/KmgQqeB7JaLlA59DX4Z7Cf8tSSglBBojvprqAZVLc54SxCPOxrxc3s4 G+40JboA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRTTe-00000009npo-14sA; Thu, 12 Nov 2026 12:00:26 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRTTc-00000009npg-39ld for linux-arm-kernel@lists.infradead.org; Thu, 12 Nov 2026 12:00:24 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id E06B163950; Thu, 12 Nov 2026 12:00:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 869391F00A05; Thu, 12 Nov 2026 12:00:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794484823; bh=wTN3UxTT/XXw7NH/F07ZSE1+SznsV7bVJZdXlw3Sm0E=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=mykMNeh5BtXxUerEKT1YuKhyGYJ7QWD8IG5KpF4NuP4taMISSoglro4vnkkgm5jw7 WQS/4vwRcKImTEfxhMYZ5wbg4cf0zsqSfNSCuEwHpTxLLpdEiTkzuh28KNZeLAVJNg ZfCkbQmePV1CQjWwx2EMjuLDIhpJighraQGEfBeHC2UHTK/MwHz7f2oBCj4SrVNuE8 h5IIE+hXfIdS625oF8CuXci5blOoZ0531mmkrv2ibJ2+zxzA7PXsQSYWh5mHmJWrB0 v/bWt32FVQ52/8TNJggbPdO6bVuM9pAUdH6G57AlDfNOf/PKeeT3jQZcm5rv//GblC jWyGILzZ6HoIw== Date: Thu, 12 Nov 2026 14:00:11 +0200 From: Mike Rapoport To: Arnd Bergmann Cc: linux-mm@kvack.org, Arnd Bergmann , Andrew Morton , Andreas Larsson , "Christophe Leroy (CS GROUP)" , Dave Hansen , "David Hildenbrand (Arm)" , Jason Gunthorpe , Linus Walleij , "Lorenzo Stoakes (ARM)" , Matthew Wilcox , Malin Jonsson , Richard Weinberger , Russell King , linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Michal Simek , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Nishanth Menon , Lucas Stach Subject: Re: [PATCH v2 5/6] arch/*: increase lowmem size to avoid highmem use Message-ID: References: <20261112112528.1116405-1-arnd@kernel.org> <20261112112528.1116405-6-arnd@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261112112528.1116405-6-arnd@kernel.org> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-15.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Nov 12, 2026 at 12:25:27PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann > > Most of the common 32-bit architectures (x86, arm, powerpc) all use the > default virtual memory layout that was already in place for i386 systems > in the 1990s, using exactly 3GiB of user TASK_SIZE, with the upper 1GiB > of addresses split between (at most 896MiB) lowmem and vmalloc. ... > Based on the above observations and the discussion at the kernel summit, > change the defaults to the most appropriate values: use 1GiB of lowmem on > non-highmem configurations, and either 2GiB or 1.75GiB of lowmem on highmem > builds, depending on what is available on the architecture. > > Signed-off-by: Arnd Bergmann Acked-by: Mike Rapoport (Microsoft) > --- > arch/arm/Kconfig | 5 ++++- > arch/arm/configs/aspeed_g5_defconfig | 1 - > arch/arm/configs/u8500_defconfig | 1 - > arch/arm/configs/vt8500_v6_v7_defconfig | 2 -- > arch/arm/mach-omap2/Kconfig | 1 - > arch/microblaze/Kconfig | 9 ++++++--- > arch/microblaze/configs/mmu_defconfig | 1 - > arch/powerpc/Kconfig | 14 +++++++++----- > arch/powerpc/configs/44x/akebono_defconfig | 1 - > arch/powerpc/configs/85xx/ksi8560_defconfig | 1 - > arch/powerpc/configs/85xx/stx_gp3_defconfig | 1 - > arch/x86/Kconfig | 4 +++- > 12 files changed, 22 insertions(+), 19 deletions(-) -- Sincerely yours, Mike.