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See http://www.infradead.org/rpr.html ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665407399; a=rsa-sha256; cv=none; b=fKaxzOtvJfwGjIRExm1Pd23on2mGMxrkZwM5qXGlJBZmEN3QquLgtyb6IcQ7LAaFAmAkva TI3APVkOXu4UQ3tKcCcJhTcGX3wA5mEPmdAHGHUabNJcdxnC54u76/XqGqRoYJJqUuO44i NI+NZMrHEVKZgK0sZZphfY/1uymDWIA= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=gGOCd3Ye; spf=none (imf15.hostedemail.com: domain of BATV+04e4e05a438ac94c6a9b+6987+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+04e4e05a438ac94c6a9b+6987+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665407399; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=gyIX3AzIymxYoNriDmltRqIhXboTWSwCFq+wUsDyIZQ=; b=YJ+IvCEYfKLtZNqJBBYOXci92/DWE9+0QyhqoIy+zJGMii+ypJzXP/GS5i5e/xE6hGtrx8 HqeQr4RWq2ZyeQAEKPhcsCxSSc1igusWlHRGQBjk8OKLsMKp+XCDo6YYgF/xjRH2pNMqQ/ t9CurridwFOmZTlq9BDSzuC1IQUL/hw= Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=gGOCd3Ye; spf=none (imf15.hostedemail.com: domain of BATV+04e4e05a438ac94c6a9b+6987+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+04e4e05a438ac94c6a9b+6987+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none X-Stat-Signature: szqiebc415953kfyqo8yxkdf4u835u48 X-Rspamd-Queue-Id: 6F75AA001E X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1665407397-586962 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 Mon, Oct 10, 2022 at 07:00:22PM +0800, zhaoyang.huang wrote: > From: Zhaoyang Huang > > __GFP_IO is believed to prevent the allocation being suspended due to accessing > physical block devices when reclaiming dirty pages. Zram is not considered as > such kind of device from kernel perspective of view. Do swap things if the system > is zram only. No, zram is not in any way special, and for sure not important enough to add special case hacks to the VM code.