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Wed, 17 Sep 2025 18:51:41 +0000 (GMT) Received: from p1lg14885.dc01.its.hpecorp.net (unknown [10.119.18.236]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by p1lg14881.it.hpe.com (Postfix) with ESMTPS id 800CA805E3B; Wed, 17 Sep 2025 18:51:28 +0000 (UTC) Received: from HPE-5CG20646DK.localdomain (unknown [16.231.227.39]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by p1lg14885.dc01.its.hpecorp.net (Postfix) with ESMTPS id D65EB801FF9; Wed, 17 Sep 2025 18:51:24 +0000 (UTC) Date: Wed, 17 Sep 2025 13:51:19 -0500 From: Kyle Meyer To: David Hildenbrand Cc: Anshuman Khandual , akpm@linux-foundation.org, corbet@lwn.net, linmiaohe@huawei.com, shuah@kernel.org, tony.luck@intel.com, jane.chu@oracle.com, jiaqiyan@google.com, Liam.Howlett@oracle.com, bp@alien8.de, hannes@cmpxchg.org, jack@suse.cz, joel.granados@kernel.org, laoar.shao@gmail.com, lorenzo.stoakes@oracle.com, mclapinski@google.com, mhocko@suse.com, nao.horiguchi@gmail.com, osalvador@suse.de, rafael.j.wysocki@intel.com, rppt@kernel.org, russ.anderson@hpe.com, shawn.fan@intel.com, surenb@google.com, vbabka@suse.cz, linux-acpi@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] mm/memory-failure: Support disabling soft offline for HugeTLB pages Message-ID: References: <8c3188da-7078-4099-973a-1d0d74db2720@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; 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Yes, -EINVAL will be returned. > So there should not be any problem, or which scenario do you have in mind? Here's an alternative approach. Do not modify the existing sysctl parameter: /proc/sys/vm/enable_soft_offline 0 - Soft offline is disabled 1 - Soft offline is enabled Instead, introduce a new sysctl parameter: /proc/sys/vm/enable_soft_offline_hugetlb 0 - Soft offline is disabled for HugeTLB pages 1 - Soft offline is enabled for HugeTLB pages and note in documentation that this setting only takes effect if enable_soft_offline is enabled. Anshuman (and David), would you prefer this? Thanks, Kyle Meyer