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b=n8nYPjTU4r/Nd5BTMnlHtCFatnQm9LWvS5aKvriT5WDtXSrov6/RjloLlQQd609BJ +G89DQh9ybFgt26PdxwGCGvYh7592kAEzLdiTh+sfsMUT11eXw0FZ472s3CR1zIgcG Uba5hjuzY3TzP4kC6eQYU7AUrBGYZ2T0O2di1ePKwMj090KwRprS8SBgMnrisIXZzf VML+x1stzh5yEq2PsKDzuTLUppGzWe6NpmaBiYsXAgSY32m26r3eJ2L7aMmoIk0+GT HkP9gazQTQYC/vi1R6za0hdZKOm3eBRZrN5AsnrpraXIhkJWIzxwlANPpWjYU7XeCh RtP7C0BAoA3aw== Date: Wed, 12 Aug 2026 11:55:03 +0100 From: "Lorenzo Stoakes (ARM)" To: Mike Rapoport Cc: Xie Yuanbin , akpm@linux-foundation.org, david@kernel.org, linmiaohe@huawei.com, ziy@nvidia.com, matthew.brost@intel.com, joshua.hahnjy@gmail.com, rakie.kim@sk.com, byungchul@sk.com, ying.huang@linux.alibaba.com, apopple@nvidia.com, nao.horiguchi@gmail.com, liam@infradead.org, vbabka@kernel.org, surenb@google.com, mhocko@suse.com, gourry@gourry.net, tony.luck@intel.com, bp@alien8.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org, liaohua4@huawei.com, lilinjie8@huawei.com Subject: Re: [PATCH] mm/Kconfig: allow user to select MIGRATION if MEMORY_FAILURE is enabled Message-ID: References: <20260812091644.224299-1-xieyuanbin1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Stat-Signature: y7hskamx8gaq6ef4jny9g8h8np1up7hn X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: A2831C0007 X-HE-Tag: 1786532125-624795 X-HE-Meta: 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 yHrEMFA5 2dffGxm8ECBz/Ld5bHBiZ/WdOgGST7qijphsNvPGBdRJmGeoIq649ILDtAhM9tFw9qSu4vLDZZbnBJcG8/OH0rUVWEeilQzOMZYGguUvfMumvoyoZv3FBBBCfgCEbdxnbQQqjRZVHFpu05lOV3lquExIIii2tOtlK49H/E+Us6fobGPSZSMrxjU8O4fkX/NzF0d2UZPd+sYBkmWOMIUU8WocuDXlxeLtxoQfCQjFfjNIeCV7WbElWmGkgXEiXEgotOsRDpjNBFnfK9oP4sI7GJH8LCYoEVcqtriWiQSHUM/t4BeH5dHRnES95yX/l2XtuUUK1wM73k7cx5tArl3wDSJSn/y8SA+fytJwwNXCH6cdgdQJtTEAzp6a3rSeylLCeKVa+Xr+5N0dTPhw= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Aug 12, 2026 at 01:45:30PM +0300, Mike Rapoport wrote: > Hi, > > On Wed, Aug 12, 2026 at 05:16:44PM +0800, Xie Yuanbin wrote: > > Currently, memory-failure can be enabled without migration. However, > > migration cannot be selected by user when memory-failure is enabled. > > > > Migration is very useful for soft_offline_page(), which may be triggered > > by correctable memory errors. Most of the anonymous or file-mapping > > faulty pages can be migrated to other healthy pages. > > > > Allow user to select MIGRATION if MEMORY_FAILURE is enabled. > > Also, select MIGRATION by default if MEMORY_FAILURE is enabled. > > Do we want to make users decide if they need MIGRATION when MEMORY_FAILURE > is enabled? > > Just make MEMORY_FAILURE select MIGRATION. NO. Explain first why the hell one of the other options that selection migration can't be enabled. Changing configs just to support a weirdo no to compaction but yes to doing soft offline for debugging or whatever isn't really convincing unless a real world, sensible use case can be stated. The kernel isn't there to allow you to have broken configs. > > > Signed-off-by: Xie Yuanbin > > --- > > mm/Kconfig | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/mm/Kconfig b/mm/Kconfig > > index 8a24c130d008..b4c217383b51 100644 > > --- a/mm/Kconfig > > +++ b/mm/Kconfig > > @@ -682,7 +682,8 @@ config NUMA_MIGRATION > > demotion for memory tiering. > > > > config MIGRATION > > - bool > > + bool "Enable page migration" if MEMORY_FAILURE > > + default y if MEMORY_FAILURE > > depends on MMU > > > > config DEVICE_MIGRATION > > -- > > 2.55.0 > > > > -- > Sincerely yours, > Mike. -- Cheers, Lorenzo