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dkim=pass header.d=fb.com header.s=facebook header.b=UIQhqB4J; spf=none (imf09.hostedemail.com: domain of "prvs=5089574f48=songliubraving@fb.com" has no SPF policy when checking 67.231.145.42) smtp.mailfrom="prvs=5089574f48=songliubraving@fb.com"; dmarc=pass (policy=reject) header.from=fb.com X-Stat-Signature: jy7dbdaut8i9ijix9bp58dfhte6o1e7x X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0708F14002A X-HE-Tag: 1648771220-879737 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Christoph,=20 > On Mar 30, 2022, at 10:37 PM, Christoph Hellwig wrote= : >=20 > On Wed, Mar 30, 2022 at 03:56:38PM -0700, Song Liu wrote: >> We prematurely enabled HAVE_ARCH_HUGE_VMALLOC for x86_64, which could ca= use >> issues [1], [2]. >>=20 >=20 > Please fix the underlying issues instead of papering over them and > creating a huge maintainance burden for others. I agree that this set is papering over the issue. And I would like=20 your recommendations here.=20 The biggest problem to me is that we (or at least myself) don't know=20 all the issues HAVE_ARCH_HUGE_VMALLOC will trigger on x86_64. Right=20 now we have a bug report from Paul, and the warning from Rick, but I am afraid there might be some other issues.=20 How about we approach it like this: Since it is still early in the release cycle (pre rc1), we can keep=20 HAVE_ARCH_HUGE_VMALLOC on for x86_64 for now and try to fix all the=20 reported issues and warnings. If things don't go very well, we can turn HAVE_ARCH_HUGE_VMALLOC off after rc4 or rc5.=20 Does this make sense? Thanks, Song