From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BC617328B6B for ; Mon, 5 Jan 2026 08:23:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767601415; cv=none; b=q6I3ItDIwox0Cn7zJuNEZBGI+kk0qF1iA+hNdShIKszbgB4FgVWiQdEzCj8y53Jk6SURop2aM/6DdWHIAnwgBmpWGjND780hHC1o3M6bqGCYO5GHoWdI4MXc7d3bVv4CHrCU3YF2Yg8JTNjXWamDdJBHrq4ufcYkc9ybzDh/2i0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767601415; c=relaxed/simple; bh=yZFREYe+kB50ig8I4QfoDGYH7fn5mVvqsTw8oxG1/Z4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=j0nmFxhPa+2zW7gjlkRudX7T+ezh0Rgk2bbLSOZKj6N4PxxTP51/TbSiQY/UTCGd7XNXJUQwwP+SvXou96NEL/mjVhXkYjCZBw4aK/6kKWPublkjqoHA8VbXMEFvOozw86yJ2ehhTiGwGkd+rL/a769IbYPExpe2+Uu7K06xXHY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=ZGXcGOjm; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=RWZ1fXc2; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ZGXcGOjm"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="RWZ1fXc2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1767601412; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=WFAlf3bglsAJtkYzmv+ft5xqaztKYGlID1/+YOBMr0o=; b=ZGXcGOjmLeGWkx/FvHO8OG4Ix2VK+O/U+h6lTSg+bUIDJIqrYivt3bKmKOd78wkGT14jKq cJ+MU6jtIuvVOCQJ60me7U3zrveQ8w38odAw7T8//11WcJLnkd+M8QMUN1u2LMug7PmCAL 2SHcXDsZ+3ve3JPQJLxFe+CgDnoUww4= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-489-aa7Il805PqC3JKsa37Mxnw-1; Mon, 05 Jan 2026 03:23:30 -0500 X-MC-Unique: aa7Il805PqC3JKsa37Mxnw-1 X-Mimecast-MFC-AGG-ID: aa7Il805PqC3JKsa37Mxnw_1767601410 Received: by mail-wm1-f70.google.com with SMTP id 5b1f17b1804b1-47918084ac1so120298775e9.2 for ; Mon, 05 Jan 2026 00:23:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1767601409; x=1768206209; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=WFAlf3bglsAJtkYzmv+ft5xqaztKYGlID1/+YOBMr0o=; b=RWZ1fXc20ZkPKj+99fWUwuXo/equGaNjQgbzREfCka0FOX2uIqLLuxl+O9HxLpwj2C iZG/W34/ARlm0hd3v9K7r6YnDdrsAN8qcmZQF+V951BjWru74fplmVNXqLEAqwpri6/5 eIEsQP+XV9aMeQokdFniLjl4ugZGFQzJNHtIeVLtOroKt8HACZ3giLnI6AA3V26BdTwc 0wEuTJ2ZwZvEblT1B0TAQUiq3V+oe+8PlUYmu92jVdhmn2z7nmZZPQ5C0IDA8vXGYP0y RPoKUQFVv/MZFhxuivyuaTJWNJ/Y1C2ie6leuq+9E9ZLMOlzC0G+RyGG2WDSJW41Zryt ki8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767601409; x=1768206209; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WFAlf3bglsAJtkYzmv+ft5xqaztKYGlID1/+YOBMr0o=; b=XQ2LDukv5Jg8C7RrWeo2l7hSgNcxmx8VocpibzJIy+oBw9DW/s3AGAzDDS3k4QdiA2 Wb9BaT4jVBFTwStEE+2kqzmrz5VgHPR9lnQgDiUBLOBBorSFNt5f47+yT0pAhIumRxqw 8mhiucrCB+etuq0p6RcI/KDu5kbPx9K3z20enIhA10g9TW9ha+sLZr5G/rWH/lUNGG/F YZBWbMyFH6BRMXjeIIz4GaD56MZeVbawYVfato7E4WiO1VqPS3rhsPUD2Qt9YIeL+eY7 mG8FOKXtoIj1zyQOh07AIYP9gjDwz9ZMq/5i3GjfEfC1QO7QdaEZRxiK7vRBSxxfMgZg Rz3Q== X-Forwarded-Encrypted: i=1; AJvYcCXRvL3VI/ru7pt3sUI57Uee9nryBI4asd+k2O8HJJ9MpcbjfCZAVs7ckrLY2P2nZyllg6Kjllw=@vger.kernel.org X-Gm-Message-State: AOJu0YxjKyBJJrwrkEr/eKWfL3/9wU6oPgka9nte9vs9BX/ohM/fRDxn UVUD2g2xP7t/WjCSZARACwEHgcpMtrudCI8nDkk2VjZqAub6IzAbPgOTLisPMCI9eItTxGX6vdd gFmbt1TNqRmQ7OT9r4Cd6gyIWn97nIr6TCMjFppSGWZ+I5S/UeaVhMSokgw== X-Gm-Gg: AY/fxX6z7CXkl9wXfJC6WOXrp+vENAI3NM47HJWaRp9vNaLyvjqMauYuC9lLt0PwkbI AJ20f3u8LjM1+M0bCA2W9VxD/TG5LinBas+4BnrZoYDs0UhhVmzholot49Py0nVyYq8lz0UEgmX sI7TUd6V1rsytFbPMhefKqyNEqoyimOE7iTnMWLE+LRJzhbmyfanDBcQmLE5G1Dmicbg/mej0Fu AjTzWhz2nLZO/OUFWfEOao34Gr46b+JgTVyxV3yy1A+/lSq9HxxeIjpN9itc5pkJ1ncn8kNXoee vHbwfebMoWeL+Wi6jfn5AGE7Y+BO5so0Ar1xrdyOsAW/NqDgAZqdZ2uB9sJNQyxw6qDDcaW8qVT K3p52ZzCo5153qYeAmY+/B+lG+8bL9s7cTw== X-Received: by 2002:a05:600c:4fd4:b0:46e:4a13:e6c6 with SMTP id 5b1f17b1804b1-47d1958a43fmr573308355e9.19.1767601409526; Mon, 05 Jan 2026 00:23:29 -0800 (PST) X-Google-Smtp-Source: AGHT+IFwNUq77RyeyS0obHX/fGtVMqKrfm8Lk7lx8bL3zrRbRdvbJ0vPOnUhK5sFwtMU1HFVUtXhCA== X-Received: by 2002:a05:600c:4fd4:b0:46e:4a13:e6c6 with SMTP id 5b1f17b1804b1-47d1958a43fmr573308005e9.19.1767601409047; Mon, 05 Jan 2026 00:23:29 -0800 (PST) Received: from redhat.com (IGLD-80-230-31-118.inter.net.il. [80.230.31.118]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-47d6d145162sm142697615e9.4.2026.01.05.00.23.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 05 Jan 2026 00:23:28 -0800 (PST) Date: Mon, 5 Jan 2026 03:23:25 -0500 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Cong Wang , Jonathan Corbet , Olivia Mackall , Herbert Xu , Jason Wang , Paolo Bonzini , Stefan Hajnoczi , Eugenio =?utf-8?B?UMOpcmV6?= , "James E.J. Bottomley" , "Martin K. Petersen" , Gerd Hoffmann , Xuan Zhuo , Marek Szyprowski , Robin Murphy , Stefano Garzarella , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Petr Tesarik , Leon Romanovsky , Jason Gunthorpe , Bartosz Golaszewski , linux-doc@vger.kernel.org, linux-crypto@vger.kernel.org, virtualization@lists.linux.dev, linux-scsi@vger.kernel.org, iommu@lists.linux.dev, kvm@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH v2 09/15] virtio_input: fix DMA alignment for evts Message-ID: References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Mailer: git-send-email 2.27.0.106.g8ac3dc51b1 X-Mutt-Fcc: =sent On non-cache-coherent platforms, when a structure contains a buffer used for DMA alongside fields that the CPU writes to, cacheline sharing can cause data corruption. The evts array is used for DMA_FROM_DEVICE operations via virtqueue_add_inbuf(). The adjacent lock and ready fields are written by the CPU during normal operation. If these share cachelines with evts, CPU writes can corrupt DMA data. Add __dma_from_device_group_begin()/end() annotations to ensure evts is isolated in its own cachelines. Signed-off-by: Michael S. Tsirkin --- drivers/virtio/virtio_input.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c index d0728285b6ce..9f13de1f1d77 100644 --- a/drivers/virtio/virtio_input.c +++ b/drivers/virtio/virtio_input.c @@ -4,6 +4,7 @@ #include #include #include +#include #include #include @@ -16,7 +17,9 @@ struct virtio_input { char serial[64]; char phys[64]; struct virtqueue *evt, *sts; + __dma_from_device_group_begin(); struct virtio_input_event evts[64]; + __dma_from_device_group_end(); spinlock_t lock; bool ready; }; -- MST