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 3B281C43327 for ; Mon, 29 Jun 2026 10:21:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3C7196B0005; Mon, 29 Jun 2026 06:21:23 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3A0416B0088; Mon, 29 Jun 2026 06:21:23 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2DD946B008A; Mon, 29 Jun 2026 06:21:23 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 0F0266B0005 for ; Mon, 29 Jun 2026 06:21:23 -0400 (EDT) Received: from smtpin13.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 79AF91205F1 for ; Mon, 29 Jun 2026 10:21:22 +0000 (UTC) X-FDA: 84932558004.13.80B7D64 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf28.hostedemail.com (Postfix) with ESMTP id D7C59C0009 for ; Mon, 29 Jun 2026 10:21:20 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=k4VqO4OP; spf=pass (imf28.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; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1782728480; b=M6beFDF4/0d7Q8WgSqDbj6a2Y3Pnylnn08nNF4KrTctU2g+BO4xl9XOSr52GSb0ndCdzBm ZtCNo1JodtnLJoStc3nfkll0uKOCucmRsKhW0UxkMNIIYJ3XUYZ4x0t7PVv/o/We6oAwFx 3+EccVcfcxSw3tHcruWaB6pvcz3fKQU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1782728480; 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=hWacwzXDsthaKuP5l9YfT3wOuzUJwz+T9Kp6WoULqsg=; b=sXpSile2qD5rExRY9URwZ/wDk5uq441LlRlet75WzzSQvL+x5zd56ZuLSD6qGOmKebEmTA i4LfTOKbwZAlVLIllcr/v9XuABPNUpao8wB3g/YzBiPevjXd/GDDCOky00veRQqASfoWJi VSwNFBh0Ly/zlFv2DfIrg0YdB5BxAHw= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=k4VqO4OP; spf=pass (imf28.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 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 6051360008; Mon, 29 Jun 2026 10:21:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78BD21F000E9; Mon, 29 Jun 2026 10:21:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782728480; bh=hWacwzXDsthaKuP5l9YfT3wOuzUJwz+T9Kp6WoULqsg=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=k4VqO4OPJ1P0VvsP9GW4oTWLcs8PBpWPWCTU+JUJEjwiSGou7TB/CSY1pd/QfM0Z6 V+eJAqwcid7N8P4lnv+QbGlS5sVkRfVSgcGwfFsJjHIPvX2TUGzYXYufY0VC467/8i +GyGXkc2NOd97DZDMCWtvUcpj2jbJI0SWw7N7/K6ZChB5mhILggGHXx+xd6OCOOUVd S43lV0tvGH4n5XkOMuff93KHY0AFMdZ5gDjvitOEmzUEL+EjsUZSkG+I4F7AZpAFe9 zEntDDN2jVfGNrCexLn2MZrL7QzkLgiMqrVBmMQ2fZLhci8b5/YTQTC8H78TvZJqnG xLGWdxP6ETgaA== Date: Mon, 29 Jun 2026 11:21:10 +0100 From: Lorenzo Stoakes To: Andrew Morton Cc: Oscar Salvador , Dave Hansen , Karsten Desler , Muchun Song , David Hildenbrand , Vlastimil Babka , "Liam R . Howlett" , Andreas Larsson , "David S . Miller" , Huacai Chen , Alexander Gordeev , Gerald Schaefer , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 0/8] Stop special-casing hugetlb mappings in get_unmapped_area Message-ID: References: <20260606035003.529685-1-osalvador@suse.de> <20260627235512.787d09b15b3d2ff9441e604a@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260627235512.787d09b15b3d2ff9441e604a@linux-foundation.org> X-Stat-Signature: fokdoafdfrouqnwtjj5ukrhuztmfmr1o X-Rspam-User: X-Rspamd-Queue-Id: D7C59C0009 X-Rspamd-Server: rspam02 X-HE-Tag: 1782728480-509083 X-HE-Meta: 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 y2LZBtlE PAn/iI5fGMWhODUysmrAkw0NyxFYKai6urTQLtuPmR8EATHXdg6BXftiAf2K4NR8snziqe5gg3pmCHDO2055AU5A+aX8pQwi6PEUuzBYZq0Jvn/HUjIiLnUbOx+Voa4U295YBJw1WNfwj/k5KBjRE9RHlgavzp/lADeTGv40m7KFEFeB+9/+OtiLEC81JwlicPZkT4beu1u4gDgcuUWl26TloaBvho63yYzxyYcwybYglBl7jmwt3srrx4A+0doWq891ZB+3qj/2IunCoYzEmyTTK7PabmPda4pc4/a8QJZgZ7bngh63SfLwz1kVpTWi4Q83Pgm5J/fw1Ose5DFn+LUTfdzZ8g0dMT+4ytN2wil2jzvI= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Jun 27, 2026 at 11:55:12PM -0700, Andrew Morton wrote: > On Sat, 6 Jun 2026 05:49:55 +0200 Oscar Salvador wrote: > > > A regression was reported on AMD 15h Family for hugetlb mappings when 'align_va_addr' > > is set [1]. > > It would be helpful to say right here that this regression results in a > runtime BUG(). Helps get attention ;) > > > Historically, for hugetlb mappings we always ignored 'align_offset' in get_unmapped_area > > functions, but after commit 7bd3f1e1a9ae ("mm: make hugetlb mappings go through > > mm_get_unmapped_area_vmflags") that was no longer the case for x86. > > > > While we could fix that by work it around in x86 code, the truth is that the current > > functioning of hugetlb mappings with get_unmapped_area functions is a bit clumsy, and > > we can do better. > > This patchset aims at two things: > > > > 1) Fix regression reported in [1] > > 2) Stop special-casing hugetlb mappings in get_unmapped_area functions > > OK, so the offending commit was about 1.5 years ago. > > Do we want to fix -stable kernels? If so, can we start out with > something minimal for backporting? And narrow down its Fixes:? > > The series was sent at an awkward time in the -rc cycle, which perhaps > explains the lack of feedback. I suggest a refresh/retest/resend to > help bring people up to speed. Yes please rebase + resend :) > > Sashiko has quite a lot to say - I hope some of it is useful? > https://sashiko.dev/#/patchset/20260606035003.529685-1-osalvador@suse.de > Cheers, Lorenzo