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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 35256E668AF for ; Sat, 20 Dec 2025 04:16:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 54A7C6B00A6; Fri, 19 Dec 2025 23:16:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 454C26B00AA; Fri, 19 Dec 2025 23:16:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0C75F6B00A7; Fri, 19 Dec 2025 23:16:17 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id D2C4B6B00A6 for ; Fri, 19 Dec 2025 23:16:16 -0500 (EST) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 9C778601EB for ; Sat, 20 Dec 2025 04:16:16 +0000 (UTC) X-FDA: 84238537152.26.805DF60 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by imf01.hostedemail.com (Postfix) with ESMTP id 346534000A for ; Sat, 20 Dec 2025 04:16:11 +0000 (UTC) Authentication-Results: imf01.hostedemail.com; spf=pass (imf01.hostedemail.com: domain of houtao@huaweicloud.com designates 45.249.212.56 as permitted sender) smtp.mailfrom=houtao@huaweicloud.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1766204174; a=rsa-sha256; cv=none; b=mqedblIikdEcT14Mkadb/UF8AvSEmcW8UNvNWAzbzm7UEpgyzjezC49tvT4ErD+ZjVbmd3 UMy6YkNTlEXvIAaOA4EkDxVScIRCr5M/QZfqJ6njZhO/kNYnjBvGzxUFF5N/nUib1hp4Kh JImdhkzPt/Olfww0w2KUIEOkOaqH3Fg= ARC-Authentication-Results: i=1; imf01.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf01.hostedemail.com: domain of houtao@huaweicloud.com designates 45.249.212.56 as permitted sender) smtp.mailfrom=houtao@huaweicloud.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1766204174; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nHSxXsmvYGLR7vfZHfzfTQz8iHaAe/U5mySPzzgTYXM=; b=ijry6X0vCeKDCVi/bDQHBPD+GPIYQzyqpMDEG4Tyjetk66ik/Tqtrttru0uu7oVWW0teak q9e8kxRKF6rGr6EIDYPg+Wwkz3CmsjoKwzBxBKYFSMmHahUXp9151I2rcprXPxmFRtU529 UVJz/g5OLy3LkxTO2IouuITxXYlUfQY= Received: from mail.maildlp.com (unknown [172.19.163.198]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTPS id 4dYB0T4lDkzKHM0K for ; Sat, 20 Dec 2025 12:15:53 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id C997C40575 for ; Sat, 20 Dec 2025 12:16:06 +0800 (CST) Received: from huaweicloud.com (unknown [10.50.87.129]) by APP4 (Coremail) with SMTP id gCh0CgD3WPn5IkZpFwpFAw--.56015S6; Sat, 20 Dec 2025 12:16:06 +0800 (CST) From: Hou Tao To: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org, linux-mm@kvack.org, linux-nvme@lists.infradead.org, Bjorn Helgaas , Logan Gunthorpe , Alistair Popple , Leon Romanovsky , Greg Kroah-Hartman , Tejun Heo , "Rafael J . Wysocki" , Danilo Krummrich , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , houtao1@huawei.com Subject: [PATCH 02/13] PCI/P2PDMA: Fix the warning condition in p2pmem_alloc_mmap() Date: Sat, 20 Dec 2025 12:04:35 +0800 Message-Id: <20251220040446.274991-3-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20251220040446.274991-1-houtao@huaweicloud.com> References: <20251220040446.274991-1-houtao@huaweicloud.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID:gCh0CgD3WPn5IkZpFwpFAw--.56015S6 X-Coremail-Antispam: 1UD129KBjvJXoW7Zr18GF15tF13WF1DAr1DWrg_yoW8Ar13pF W3GF17GrWktr43JF4DJ3Z8ury5Aan3uFWUKFWUXw1UuF13urWjkw48tF95Jry5try8Ar1S qFs8ur1jyF1DAaUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPab4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW7JVWDJwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r126r1DMcIj6I8E87Iv67AKxVW8Jr0_Cr1UMcvjeVCFs4IE7xkE bVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7 AKxVW8ZVWrXwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02 F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_Wr ylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7Cj xVAFwI0_Cr0_Gr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxV WUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxU xXTmDUUUU X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-Rspamd-Queue-Id: 346534000A X-Stat-Signature: shey8g9jnjoee4z54rdw3ychqcgh31pk X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1766204171-187608 X-HE-Meta: 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 BgvB89Aj q47TEeVNZlA1SzuXC4n/QCdmjiz6SsbinwdCpw3FMSub/yTxgq24RjPsfO7AwqX18ptc3B6bm/WPRCdf6AaJtyZDTWHzxkiFbMhnNeznNfM7FeTVqcuI/dhL+DRhTwr+v0OCRJKzwmbWpNps= 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: List-Subscribe: List-Unsubscribe: From: Hou Tao Commit b7e282378773 has already changed the initial page refcount of p2pdma page from one to zero, however, in p2pmem_alloc_mmap() it uses "VM_WARN_ON_ONCE_PAGE(!page_ref_count(page))" to assert the initial page refcount should not be zero and the following will be reported when CONFIG_DEBUG_VM is enabled: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x380400000 flags: 0x20000000002000(reserved|node=0|zone=4) raw: 0020000000002000 ff1100015e3ab440 0000000000000000 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_WARN_ON_ONCE_PAGE(!page_ref_count(page)) ------------[ cut here ]------------ WARNING: CPU: 5 PID: 449 at drivers/pci/p2pdma.c:240 p2pmem_alloc_mmap+0x83a/0xa60 Fix by using "page_ref_count(page)" as the assertion condition. Fixes: b7e282378773 ("mm/mm_init: move p2pdma page refcount initialisation to p2pdma") Signed-off-by: Hou Tao --- drivers/pci/p2pdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 218c1f5252b6..dd64ec830fdd 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -147,7 +147,7 @@ static int p2pmem_alloc_mmap(struct file *filp, struct kobject *kobj, * we have just allocated the page no one else should be * using it. */ - VM_WARN_ON_ONCE_PAGE(!page_ref_count(page), page); + VM_WARN_ON_ONCE_PAGE(page_ref_count(page), page); set_page_count(page, 1); ret = vm_insert_page(vma, vaddr, page); if (ret) { -- 2.29.2