From nobody Mon Feb 9 22:38:16 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1575006043; cv=none; d=zohomail.com; s=zohoarc; b=PPayG19f71XH109BqxBlLJgZSGTAmS8e1lrNrKgrRi7gd4co2FM1HDWRDQTlBWsfHG5wr5iXWdUsJb6m4rddPua5NI30/l1b+5z/8b+n0w6rO4UAzIzI3sbt7Fxm6HUtIwsWEwf860Yky/XLBjosrtbBOcqg7mAvZ9XM4pYZbPw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1575006043; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=8+obQ9vv8gaEap76eCbThOBFcQPdRw1eITXlJ5KgZCM=; b=haOAiPVDUzJWTOkQv5m/hT9o9BG82CtWpRzexg2i7Q3Y2xQ7JP9IyfgbVZhpk8mXsmIAFfaOQn3fy1tbUGYvmhKMD+ej3z8jm+a/2Rz2JoZQJZrGg9Jhp5u7sVYHljuD5CVJtH6dEe6j6nI+Z41nWdxk1y8XDJWs/Zt6GuhYK68= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1575006043116776.2385167798515; Thu, 28 Nov 2019 21:40:43 -0800 (PST) Received: from localhost ([::1]:55042 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iaZ1E-0005OH-O6 for importer@patchew.org; Fri, 29 Nov 2019 00:40:40 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:55624) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iaYuw-0002gj-0W for qemu-devel@nongnu.org; Fri, 29 Nov 2019 00:34:13 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iaYut-0002ou-Eh for qemu-devel@nongnu.org; Fri, 29 Nov 2019 00:34:09 -0500 Received: from ozlabs.org ([2401:3900:2:1::2]:52047) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iaYur-0002M8-5U; Fri, 29 Nov 2019 00:34:07 -0500 Received: by ozlabs.org (Postfix, from userid 1007) id 47PNTz6JDlz9sR2; Fri, 29 Nov 2019 16:33:59 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1575005639; bh=cenYxuwXEyURgovfy5vrBzyXXCpM0tGcpKxNSH0Fqxc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FiT9oC31/HOeacIXfVMW4+tCI46DYubpuENLGUMvG23cqROaEBLhXMtZh+cwg3RBA qQXkaE3rPMBlJZzQoS4Qanu+qusXklombD2dPko0KteLGEoq7zACsN+uY57nRQShPb aoTyrnRCEAzX6JCQgwT9FEWdOkwEvDQEc5x5/6Eg= From: David Gibson To: groug@kaod.org, clg@kaod.org Subject: [for-5.0 2/4] spapr: Improve handling of fdt buffer size Date: Fri, 29 Nov 2019 16:33:54 +1100 Message-Id: <20191129053356.232413-3-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191129053356.232413-1-david@gibson.dropbear.id.au> References: <20191129053356.232413-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2401:3900:2:1::2 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: lvivier@redhat.com, David Gibson , qemu-ppc@nongnu.org, mdroth@linux.vnet.ibm.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" Previously, spapr_build_fdt() constructed the device tree in a fixed buffer of size FDT_MAX_SIZE. This is a bit inflexible, but more importantly it's awkward for the case where we use it during CAS. In that case the guest firmware supplies a buffer and we have to awkwardly check that what we generated fits into it afterwards, after doing a lot of size checks during spapr_build_fdt(). Simplify this by having spapr_build_fdt() take a 'space' parameter. For the CAS case, we pass in the buffer size provided by SLOF, for the machine init case, we continue to pass FDT_MAX_SIZE. Signed-off-by: David Gibson Reviewed-by: Cedric Le Goater Reviewed-by: Greg Kurz --- hw/ppc/spapr.c | 33 +++++++++++---------------------- 1 file changed, 11 insertions(+), 22 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index d9c9a2bcee..d34e317f48 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -917,7 +917,8 @@ static bool spapr_hotplugged_dev_before_cas(void) return false; } =20 -static void *spapr_build_fdt(SpaprMachineState *spapr, bool reset); +static void *spapr_build_fdt(SpaprMachineState *spapr, bool reset, + size_t space); =20 int spapr_h_cas_compose_response(SpaprMachineState *spapr, target_ulong addr, target_ulong size, @@ -930,24 +931,17 @@ int spapr_h_cas_compose_response(SpaprMachineState *s= papr, return 1; } =20 - if (size < sizeof(hdr) || size > FW_MAX_SIZE) { - error_report("SLOF provided an unexpected CAS buffer size " - TARGET_FMT_lu " (min: %zu, max: %u)", - size, sizeof(hdr), FW_MAX_SIZE); + if (size < sizeof(hdr)) { + error_report("SLOF provided insufficient CAS buffer " + TARGET_FMT_lu " (min: %zu)", size, sizeof(hdr)); exit(EXIT_FAILURE); } =20 size -=3D sizeof(hdr); =20 - fdt =3D spapr_build_fdt(spapr, false); + fdt =3D spapr_build_fdt(spapr, false, size); _FDT((fdt_pack(fdt))); =20 - if (fdt_totalsize(fdt) + sizeof(hdr) > size) { - g_free(fdt); - trace_spapr_cas_failed(size); - return -1; - } - cpu_physical_memory_write(addr, &hdr, sizeof(hdr)); cpu_physical_memory_write(addr + sizeof(hdr), fdt, fdt_totalsize(fdt)); trace_spapr_cas_continue(fdt_totalsize(fdt) + sizeof(hdr)); @@ -1197,7 +1191,8 @@ static void spapr_dt_hypervisor(SpaprMachineState *sp= apr, void *fdt) } } =20 -static void *spapr_build_fdt(SpaprMachineState *spapr, bool reset) +static void *spapr_build_fdt(SpaprMachineState *spapr, bool reset, + size_t space) { MachineState *machine =3D MACHINE(spapr); MachineClass *mc =3D MACHINE_GET_CLASS(machine); @@ -1207,8 +1202,8 @@ static void *spapr_build_fdt(SpaprMachineState *spapr= , bool reset) SpaprPhbState *phb; char *buf; =20 - fdt =3D g_malloc0(FDT_MAX_SIZE); - _FDT((fdt_create_empty_tree(fdt, FDT_MAX_SIZE))); + fdt =3D g_malloc0(space); + _FDT((fdt_create_empty_tree(fdt, space))); =20 /* Root node */ _FDT(fdt_setprop_string(fdt, 0, "device_type", "chrp")); @@ -1723,19 +1718,13 @@ static void spapr_machine_reset(MachineState *machi= ne) */ fdt_addr =3D MIN(spapr->rma_size, RTAS_MAX_ADDR) - FDT_MAX_SIZE; =20 - fdt =3D spapr_build_fdt(spapr, true); + fdt =3D spapr_build_fdt(spapr, true, FDT_MAX_SIZE); =20 rc =3D fdt_pack(fdt); =20 /* Should only fail if we've built a corrupted tree */ assert(rc =3D=3D 0); =20 - if (fdt_totalsize(fdt) > FDT_MAX_SIZE) { - error_report("FDT too big ! 0x%x bytes (max is 0x%x)", - fdt_totalsize(fdt), FDT_MAX_SIZE); - exit(1); - } - /* Load the fdt */ qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt)); cpu_physical_memory_write(fdt_addr, fdt, fdt_totalsize(fdt)); --=20 2.23.0