From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3BDD8C433EF for ; Fri, 8 Jul 2022 16:38:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239060AbiGHQij (ORCPT ); Fri, 8 Jul 2022 12:38:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238182AbiGHQie (ORCPT ); Fri, 8 Jul 2022 12:38:34 -0400 Received: from wout4-smtp.messagingengine.com (wout4-smtp.messagingengine.com [64.147.123.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5529EE02B; Fri, 8 Jul 2022 09:38:33 -0700 (PDT) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.west.internal (Postfix) with ESMTP id 15C16320098B; Fri, 8 Jul 2022 12:38:31 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute2.internal (MEProxy); Fri, 08 Jul 2022 12:38:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= invisiblethingslab.com; h=cc:cc:content-transfer-encoding:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:sender:subject:subject:to:to; s=fm2; t= 1657298311; x=1657384711; bh=ig8GcuWSg8QXfRSyjrDA6qxRNwqouf+sjZK 0qbI6A6M=; b=UMimGG2Uo4lY7atREe2OP8S17UwSlHLVe/8rwvtepafcUCIerM/ +faYLQMq+QWk2ePkEKdH0xisdPrkUY8RM9HfbybzshoqXScDXiWukeOrL8SBiC7q 2bYf7P7djsCJm4p3x9qG9ovXkVz/nuxRmuH/JUDYCnAdC0pxNACm1AAb33Z9rpEt uFcN0NbUHA2r7MLfrnH7a/qwob9ehzd/2Wh/ETUf0iH2lWlBpIMGjq7IiY046E80 OgNKBOHEZE63eLhNRPmXdYjbGVAnVYvjarOgO6Jg83zGr23/yK4kAfsCaiwfMnTm zBpmMftHJCm+TP4J8BoN0zlc3y0JpPN4JjQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1657298311; x=1657384711; bh=ig8GcuWSg8QXf RSyjrDA6qxRNwqouf+sjZK0qbI6A6M=; b=KW6PkF5vTTfz/RditvRVGIbRHVSo2 hJGbgtx3KXGhhsTRKqRnP+nWRgfxd79rqg4T3AXAnxqw7p1zunuMAGmkTZ6PKogF z2phKIH8YtcZMqizRwy9TqWcgctfhiWX5BVG6uGylSxM1xEjlVAsePMbGRviqOtY QMm6JSAdF9T3DPgMO8DKwAWm/1RIAf4qaFx3ql+dXq97Uaas+PJws0B+Rl56YoAo 4t9O60v4OzSZ6uH0x4zdd1gNwEI163U1noKNYLtsb7lK8BcNDDwThumvP2n3uGVm hh/TH9YT+otbypQrg35LjestKqW97vZdxb36ixcW3O+eKJK0OaYMD1gxg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrudeijedguddtfecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvfevufffkffojghfggfgsedtkeertdertddtnecuhfhrohhmpeffvghm ihcuofgrrhhivgcuqfgsvghnohhurhcuoeguvghmihesihhnvhhishhisghlvghthhhinh hgshhlrggsrdgtohhmqeenucggtffrrghtthgvrhhnpeejffejgffgueegudevvdejkefg hefghffhffejteekleeufeffteffhfdtudehteenucevlhhushhtvghrufhiiigvpedtne curfgrrhgrmhepmhgrihhlfhhrohhmpeguvghmihesihhnvhhishhisghlvghthhhinhhg shhlrggsrdgtohhm X-ME-Proxy: Feedback-ID: iac594737:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 8 Jul 2022 12:38:30 -0400 (EDT) From: Demi Marie Obenour To: Juergen Gross , Greg KH , Stefano Stabellini , Oleksandr Tyshchenko , Demi Marie Obenour Cc: Linux kernel regressions , stable@vger.kernel.org, Linux kernel mailing list , Xen developer discussion Subject: [PATCH 4.14] Ignore failure to unmap -1 Date: Fri, 8 Jul 2022 12:37:46 -0400 Message-Id: <20220708163750.2005-3-demi@invisiblethingslab.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220708163750.2005-1-demi@invisiblethingslab.com> References: <20220708163750.2005-1-demi@invisiblethingslab.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The error paths of gntdev_mmap() can call unmap_grant_pages() even though not all of the pages have been successfully mapped. This will trigger the WARN_ON()s in __unmap_grant_pages_done(). The number of warnings can be very large; I have observed thousands of lines of warnings in the systemd journal. Avoid this problem by only warning on unmapping failure if the handle being unmapped is not -1. The handle field of any page that was not successfully mapped will be -1, so this catches all cases wherr unmapping can legitimately fail. Suggested-by: Juergen Gross Cc: stable@vger.kernel.org Signed-off-by: Demi Marie Obenour Fixes: 2fe26a9a7048 ("xen/gntdev: Avoid blocking in unmap_grant_pages()") --- drivers/xen/gntdev.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 2827015604fbaa45f0ca60c342bbf71ce4132dec..799173755b785e2f3e2483855f75af1eba8e9373 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -393,7 +393,8 @@ static void __unmap_grant_pages_done(int result, unsigned int offset = data->unmap_ops - map->unmap_ops; for (i = 0; i < data->count; i++) { - WARN_ON(map->unmap_ops[offset+i].status); + WARN_ON(map->unmap_ops[offset+i].status && + map->unmap_ops[offset+i].handle != -1); pr_debug("unmap handle=%d st=%d\n", map->unmap_ops[offset+i].handle, map->unmap_ops[offset+i].status); -- Sincerely, Demi Marie Obenour (she/her/hers) Invisible Things Lab