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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5EA53C3064D for ; Fri, 28 Jun 2024 08:12:42 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sN6if-0002sZ-VR; Fri, 28 Jun 2024 04:12:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sN6ie-0002s4-FD for qemu-devel@nongnu.org; Fri, 28 Jun 2024 04:12:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sN6ic-00057t-Im for qemu-devel@nongnu.org; Fri, 28 Jun 2024 04:12:32 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719562349; h=from:from:reply-to: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=IS+Yz4+qV2Bgsf/Pp17U4lhZGBAGViAT+TUtb8f80GQ=; b=isMddxEbKL3rdJca/983fkW42eVFcxmdX4OhgA59+9oOly/S6rfGfAwMqu6Lq/kCqDym6b wkPfAzQMIc8vvMwWHr3aaDD4+6B2adFB5r64LXhZ0Sl3tocI1SZ7iHiCHkTr7u7MWlE7Kg iQCx9i9Y8xX6e7hY8eats6K9hlpXWZM= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-694-s_DQXfbVNnWnWxdq0lmfAg-1; Fri, 28 Jun 2024 04:12:25 -0400 X-MC-Unique: s_DQXfbVNnWnWxdq0lmfAg-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 292201944DDB; Fri, 28 Jun 2024 08:12:24 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.106]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BFE6F300021A; Fri, 28 Jun 2024 08:12:22 +0000 (UTC) Date: Fri, 28 Jun 2024 09:12:19 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Gregor Haas Cc: qemu-devel@nongnu.org, yaoxt.fnst@fujitsu.com Subject: Re: [PATCH v2] hw/core/loader: allow loading larger ROMs Message-ID: References: <20240628005817.1672298-1-gregorhaas1997@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20240628005817.1672298-1-gregorhaas1997@gmail.com> User-Agent: Mutt/2.2.12 (2023-09-09) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.212, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Jun 27, 2024 at 05:58:17PM -0700, Gregor Haas wrote: > The read() syscall is not guaranteed to return all data from a file. The > default ROM loader implementation currently does not take this into account, > instead failing if all bytes are not read at once. This change loads the ROM > using load_image_size() instead, which correctly reads all data using > multiple calls to read(). > > Signed-off-by: Gregor Haas > --- > hw/core/loader.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/hw/core/loader.c b/hw/core/loader.c > index 2f8105d7de..8216781a75 100644 > --- a/hw/core/loader.c > +++ b/hw/core/loader.c > @@ -1115,14 +1115,13 @@ ssize_t rom_add_file(const char *file, const char *fw_dir, > > rom->datasize = rom->romsize; > rom->data = g_malloc0(rom->datasize); > - lseek(fd, 0, SEEK_SET); > - rc = read(fd, rom->data, rom->datasize); > + close(fd); > + rc = load_image_size(rom->path, rom->data, rom->datasize); > if (rc != rom->datasize) { > fprintf(stderr, "rom: file %-20s: read error: rc=%zd (expected %zd)\n", > rom->name, rc, rom->datasize); > goto err; > } > - close(fd); This method can be simplified much more. All of the original 'open', lseek, g_malloc0, read & close, can be replaced by something approximately like this (untested): g_autoptr(GError) gerr = NULL; if (!g_file_get_contents(file, &rom->data, &rom->datasize, &gerr)) { fprintf(stderr, "unable to load ROM '%s': %s", file, gerr->message); goto err; } With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|