From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794746627; b=GZmd6X9wumk6HHOO7x7iIfb1hESpUCgwN937bBCUJqqMB9GgEPoZNqevVnvgG30Z45Nh xT15VgyoutwuG7lO+9jAdVWGbI4RmfAOsiTIWJJdlOXmDktydVNS8bL7FNs7B66PLnuJN mGpIwsWEqZsIFt4fBSEUOGVmIv10uGPxp20HsNsNVFe+ZoKZt6objBW8myAHS9HcnXIz2 cG/AW5KNjzQz8z4KS6/1bRoKiF4GUAdWqZvIaCdkRLFPKxVbastHVE/dxe6Pug729veoB TLTGxBatHcmCw7RoWsOHI1w4/IG4kp9VAtlnHFItYTy0qmC8F2f9/uGjPxIpo6v2V6g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794746627; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=ItLIVfR1UvySuEEyBIwhJcSgZBhLRZU0DncWL/OBsMk=; b=h/jtpU/dMDfMyeCgxzuOuSQrngFxnzLWzUurPD1/Qf9NwI7RvzgvkBGlW/tz60ipXRHd Dvoc0r0Ql7K510Z51nfv2phBSQUt5WOvK8OaykDGIGPuPC2DCo7pNBu/V8tZjwKxX4qBJ TZLLMWolYuAJ5KPvCl5sDE/oy9ClWaDbLV2uK4QT/HSQzvch4Wy0hb0zTUnwWnuq/Q9IQ Rn10Lt4CtXohs9wS6HNYkD8HLJnBOjTk1Sx2722Bz+lg4lUdwhj2DA9fcFAU0sR8HWCZO 3uh0FCs3GZm4OK4UMPxuoSjj0E+fn3wON0wKnf0PnBt7DpZYDyfS500GIxn+Qhk+NFA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=kQUCoZgo; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0A334606A327; Sun, 15 Nov 2026 12:43:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=kQUCoZgo Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55E391F000C4; Sun, 15 Nov 2026 12:43:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794746626; bh=ItLIVfR1UvySuEEyBIwhJcSgZBhLRZU0DncWL/OBsMk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=kQUCoZgoZYY0fcgF/LYN5sg/FhigfV0RmeA/86U/4sCjPuPGBE7pd/oHPIVJVMHeI 2IlWDFrE2uywqCCL3Jj4I0gGH96okLxf/UhYvS5kk81lBsUXiLT0XG4bnC3fmIIbQT FAXlrPGLPbzjzk/slqBIXIi2bdAAItZxNHxkbUNb2Djd2SOHBSqePSUK+11mTmke2o pFbiltFhIDDUt2GyBFurnDfb1H58W6ugxVtf1bPJT4VmYgHVtu2+LnWlCcDTfojdcw G5zEG77A/QC/3H4C0a3ofuIthVL6eskpAnW0W6WqaYJziKQzUOtpAXQO19MXd54q0C fv05uW8CCyplA== Date: Sun, 15 Nov 2026 12:43:34 +0000 From: "Lorenzo Stoakes (ARM)" To: Chris Down Cc: David Hildenbrand , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , David Rientjes , Shakeel Butt , Andrew Morton , Jann Horn , Pedro Falcato , "Matthew Wilcox (Oracle)" , Jan Kara , Nhat Pham , Johannes Weiner , Zi Yan , Matthew Brost , Joshua Hahn , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Usama Arif , Kairui Song , Balbir Singh , =?utf-8?B?SsOpcsO0bWU=?= Glisse , Kiryl Shutsemau , Yu-cheng Yu , Dave Hansen , Dennis Zhou , Tejun Heo , Christoph Lameter , Peng Fan , Josef Bacik , Chris Mason , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Borislav Petkov (AMD)" , Mark Brown , "Dennis Zhou (Facebook)" , Rick Edgecombe , stable@vger.kernel.org Subject: Re: [PATCH v2 08/13] mm/migrate_device: fix ksmd oops on a migrated KSM page Message-ID: References: <20261113-mason-migrate-et-al-fixes-v2-0-50a2ed382b61@kernel.org> <20261113-mason-migrate-et-al-fixes-v2-8-50a2ed382b61@kernel.org> <20261114115657.f63de4714929f7af@chrisdown.name> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261114115657.f63de4714929f7af@chrisdown.name> On Sat, Nov 14, 2026 at 11:56:57AM -0800, Chris Down wrote: > Hi Lorenzo, > > Lorenzo Stoakes (ARM) writes: > > [ ljs: tweak commit message, comment, also refuse device coherent ] > > Alistair's Reviewed-by on v1 came with the argument that KSM pages should > still be able to go to device coherent memory [1], which is the opposite of > what this does now, so it's probably worth checking that he's happy for it > to be carried over. Going by what ksmd does with zone device pages, the > change itself looks right to me. Given the endless waves of AI fixes I think giving a little slack is fair on details :) But, yes, that was a mistake so - apologies Alistair, let me know if that's OK. > > I've tested the device private case. Without this the process hangs the > next time it touches one of the pages, and with it the migration is > refused and the pages stay merged. > > [1] https://lore.kernel.org/r/avTu3LmscsttRVRp@nvdebian.thelocal > > Reviewed-by: Chris Down > Tested-by: Chris Down Thanks! -- Cheers, Lorenzo