From nobody Thu Apr 2 14:10:39 2026 Received: from mail-pf1-f172.google.com (mail-pf1-f172.google.com [209.85.210.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED57337D138 for ; Thu, 26 Feb 2026 11:55:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772106964; cv=none; b=f/hEENdNaUZwdWHDRq3TrsGtptzqItIxgs76VuYjScGmDuMigowqQROwWtFYWQpKJ4BF9hXjF0USCfu27stEbeCajAhEgLykWiAs+A/9dG/F2mMMGkcy+mw5nQtjT5+W6EoXXfiNOJdHNW4z4g5dRDoWuPKXts03g7VN0W6603U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772106964; c=relaxed/simple; bh=uBDI6vCLVayNa9JEpUxQbP6AJj9VHRh0JPtcRkORuNQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EWVgCTTKrUlNKTpvObmHBpfpWlXSOknZ6mz6uFiGX2+CGvD1j7Myr4KS3wbLqezqKjv1kPLGOIOMnJJv7rgPrQiligUEnIOMDpjgMKtzLPoLHgtF1nchLWH0fcU2Rh0ysTbq1TO8X/g/xloKCMgWAOKqnhvmUEXgXnG9s8RZCXA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com; spf=pass smtp.mailfrom=bytedance.com; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b=J77iMZeg; arc=none smtp.client-ip=209.85.210.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bytedance.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b="J77iMZeg" Received: by mail-pf1-f172.google.com with SMTP id d2e1a72fcca58-82418b0178cso467981b3a.1 for ; Thu, 26 Feb 2026 03:55:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1772106959; x=1772711759; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0M73OcDWXDbjnvZuhTobLpl4M5OeahGpDzSfF/B7/1g=; b=J77iMZegFSSqF4JxMYrDHl/mSot+BwXa5oKBXA3vByHaoCbmajdZlMU9O+746DKlDk z0Y6HtaCBivCe5BrIor5bTVO3qBpdo/325MMrRuVARbydSGOo3ADB1oUKNsS6EwQISVr g6v4xotiNZvRtvKLhFjomjpS8aZqfdEenxyyIztt4oTFfGcINVdokf/QxOW5ozjAnRJI D80TNfhEybdTLaJAqVyYTrdHDr4GbQ7Xv5LOzu4yhBFVOUt39oFZ2g4PhjIXsfx83LUi 1vm54fShyrRJabm7LUuExBKhhdfnWVvboo0IHDz0az1zkEDnVQqYeSu8dfiUuLmFnbJV 0LqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772106959; x=1772711759; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=0M73OcDWXDbjnvZuhTobLpl4M5OeahGpDzSfF/B7/1g=; b=JzsSGk6H5iHv4+OZTMCKsYzOjz1UptzN64joCEA0riX5SzGSkBcTTfx/0oBbL2cwke UDbdIrvzItWZglZ+xZ6OtSIUuWyNCxDDIxB8NgVNy8QFbne/olfEk5rfeXa8hbCFHhGf EAZX63KUtBcezbSwF4De9PtXckXzDeEzMpN3iEZduYGomYwDnbYeHbKW/ORTWIYXNy1m E58wGFPT0gf6QMvhRdSlGy/1NxisXEc20rDZgXD8BZ7g+I5OO5hCGAZQXbPoGsSfB6O8 xcymaDXDNqpvfKffp6xtvWuAK3NUK6HIrDsUZ1VGfYVXfAwZV7MGvd6m4hdofFcebJaH U+rg== X-Forwarded-Encrypted: i=1; AJvYcCWhPfFvDhgArFyF4Io0M0CYU3japmHWQcTp9ZNXnY0krjkqhdqXLmTMiudySuKGA2L7aOGAAFtoetRcNr0=@vger.kernel.org X-Gm-Message-State: AOJu0Yy45xAxbRmhyEert5dQME4Sh/U7j3ICDgiyJjtXAc4N2uB/lcw3 PBKm2SAzDmZD+rQ8W3flLXMO5QUh8eL6p8VtD4Xmz/jM5QqgrjwSC87pkgGK2UMpbskLKxHwK8c RiNgM9CY8lA== X-Gm-Gg: ATEYQzwx6lBEETz6x1lnVy+Cso1ySc0OOYxfm83lQCBQ2PyX79Lt11Krh/MHi3MKdBY jy4o79gw+qqlydVt7kAt2ZPMdcz6qHbSZ8ReVQn+kN9xnWaJ6dbHmuH00nDOK2O2NZ+7rT0asKz RcAD39KGJgq+zCmpmzzuNTYX6RZCaZI8h9Kj4KMgNmE0mFHJ0PNMwmNSd3EcvsOdlJrKq4RW8Et nTugIKcUaCxHEw1dcNoaMR66SLUQkMod2LHS/RoE9eljP7eLRT1oXIlkDn3Dg0y4rfAkPIkpfg4 SVjUL3dhgNMmNoAh7tZMdIT3Zybrht72nT2vNCl9pmyq2Z+Mh+FipxVwYgSVgV2X1gAiG4yNbFC /wU6PtpzC3P3b79N9JWkDa147oxMVpWUE+UKDSo4kFgvGim7obkobJIOaWHCuRR65YZtwCCv0aK Pr18OCBmxtXWhvfGxxZC7YRXbvzuZHhhLbeXJNl0LxFPaOT6dSLLLV0WjKJCfsUElC22fxiOeTy 9bIGg== X-Received: by 2002:a17:90a:d646:b0:359:28b9:5f64 with SMTP id 98e67ed59e1d1-3593da6ffffmr1974038a91.6.1772106958977; Thu, 26 Feb 2026 03:55:58 -0800 (PST) Received: from tianci-mac.bytedance.net ([61.213.176.5]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-359130712bcsm2390815a91.7.2026.02.26.03.55.56 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Thu, 26 Feb 2026 03:55:58 -0800 (PST) From: Zhang Tianci To: mst@redhat.com, jasowang@redhat.com Cc: xuanzhuo@linux.alibaba.com, eperezma@redhat.com, marco.crivellari@suse.com, anders.roxell@linaro.org, virtualization@lists.linux.dev, linux-kernel@vger.kernel.org, Zhang Tianci , Xie Yongji Subject: [PATCH v4 1/2] vduse: Requeue failed read to send_list head Date: Thu, 26 Feb 2026 19:55:49 +0800 Message-ID: <20260226115550.1814-2-zhangtianci.1997@bytedance.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20260226115550.1814-1-zhangtianci.1997@bytedance.com> References: <20260226115550.1814-1-zhangtianci.1997@bytedance.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" When copy_to_iter() fails in vduse_dev_read_iter(), put the message back at the head of send_list to preserve FIFO ordering and retry the oldest pending request first. Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace") Reported-by: Michael S. Tsirkin Suggested-by: Xie Yongji Signed-off-by: Zhang Tianci Reviewed-by: Xie Yongji Acked-by: Jason Wang --- drivers/vdpa/vdpa_user/vduse_dev.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vd= use_dev.c index ae357d014564c..b37f18a0ce6fd 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -194,6 +194,12 @@ static void vduse_enqueue_msg(struct list_head *head, list_add_tail(&msg->list, head); } =20 +static void vduse_enqueue_msg_head(struct list_head *head, + struct vduse_dev_msg *msg) +{ + list_add(&msg->list, head); +} + static void vduse_dev_broken(struct vduse_dev *dev) { struct vduse_dev_msg *msg, *tmp; @@ -354,7 +360,7 @@ static ssize_t vduse_dev_read_iter(struct kiocb *iocb, = struct iov_iter *to) spin_lock(&dev->msg_lock); if (ret !=3D size) { ret =3D -EFAULT; - vduse_enqueue_msg(&dev->send_list, msg); + vduse_enqueue_msg_head(&dev->send_list, msg); goto unlock; } vduse_enqueue_msg(&dev->recv_list, msg); --=20 2.39.5