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x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=1urU150g; spf=pass (imf03.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1661650824; a=rsa-sha256; cv=none; b=3ojjwM/Lizxs8RBjnzs5qRN8nv/v48xZ+/29beJ9tHx1m7MP2qIkCWTlb+fPL15f4lpQ/s 79JR5RDM5t2YL0n+Hlo72xTtK9ucTQOUTY88i41wZXSKtsT8QPcw69zYG9DPDcWR25sURj 3lRX64YFUuZWAPbN+gvZVgY/aoOubK0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1661650824; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=7Tr1k8+/gHp0og7VlNI1RIHgQfHUw2TTyMVWS7UX+OM=; b=t9C8jOw3H8AJUJsNtCSFsHSrfovcw1geWEMstzx0o5iW+ZCXf+eFbMXwfie+u1+ihYzvd/ QvcsL87dG/fJ+c/VwL9d0/O9f84u04cuT8+qibKbqYFSoen65qvIHlI1HCJkZsEWevQg6g vAahUVCYyudWMZ4wWmDj4YTCMXHxWT0= Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=1urU150g; spf=pass (imf03.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Stat-Signature: rz44an89ybzyeekyjknw4jitzcubud15 X-Rspamd-Queue-Id: 51DC320020 X-Rspam-User: X-Rspamd-Server: rspam04 X-HE-Tag: 1661650824-621607 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: On Sat, 27 Aug 2022 17:59:32 -0700 John Hubbard wrote: > > /* The zero page is always allowed to be pinned. */ Wow, that's really verbose :) --- a/include/linux/mm.h~mm-re-allow-pinning-of-zero-pfns-again-fix +++ a/include/linux/mm.h @@ -1544,11 +1544,7 @@ static inline bool is_longterm_pinnable_ if (mt == MIGRATE_CMA || mt == MIGRATE_ISOLATE) return false; #endif - /* - * The zero page might reside in a movable zone, however it may not - * be migrated and can therefore be pinned. The vfio subsystem pins - * user mappings including the zero page for IOMMU translation. - */ + /* The zero page may always be pinned */ if (is_zero_pfn(page_to_pfn(page))) return true; _