From patchwork Mon Sep 4 09:06:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13373612 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 91664C83F33 for ; Mon, 4 Sep 2023 09:08:19 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qd5Yl-0003aX-3m; Mon, 04 Sep 2023 05:07:52 -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 1qd5Yd-0003Ja-D9; Mon, 04 Sep 2023 05:07:47 -0400 Received: from gandalf.ozlabs.org ([150.107.74.76]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qd5Yb-0003r2-3X; Mon, 04 Sep 2023 05:07:43 -0400 Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4RfN7w0yrpz4wxW; Mon, 4 Sep 2023 19:07:40 +1000 (AEST) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4RfN7t0K1sz4wxN; Mon, 4 Sep 2023 19:07:37 +1000 (AEST) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-ppc@nongnu.org, qemu-devel@nongnu.org Cc: Daniel Henrique Barboza , Nicholas Piggin , Pavel Dovgalyuk , =?utf-8?q?C=C3=A9dric_Le_Goate?= =?utf-8?q?r?= Subject: [PULL 24/35] spapr: Fix record-replay machine reset consuming too many events Date: Mon, 4 Sep 2023 11:06:19 +0200 Message-ID: <20230904090630.725952-25-clg@kaod.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230904090630.725952-1-clg@kaod.org> References: <20230904090630.725952-1-clg@kaod.org> MIME-Version: 1.0 Received-SPF: pass client-ip=150.107.74.76; envelope-from=SRS0=kZzc=EU=kaod.org=clg@ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Nicholas Piggin spapr_machine_reset gets a random number to populate the device-tree rng seed with. When loading a snapshot for record-replay, the machine is reset again, and that tries to consume the random event record again, crashing due to inconsistent record Fix this by saving the seed to populate the device tree with, and skipping the rng on snapshot load. Acked-by: Pavel Dovgalyuk Signed-off-by: Nicholas Piggin Signed-off-by: Cédric Le Goater --- include/hw/ppc/spapr.h | 1 + hw/ppc/spapr.c | 12 +++++++++--- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index f47e8419a575..f4bd204d8633 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -204,6 +204,7 @@ struct SpaprMachineState { uint32_t fdt_size; uint32_t fdt_initial_size; void *fdt_blob; + uint8_t fdt_rng_seed[32]; long kernel_size; bool kernel_le; uint64_t kernel_addr; diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index c0b0ada121f9..f7cc6a890f45 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1022,7 +1022,6 @@ static void spapr_dt_chosen(SpaprMachineState *spapr, void *fdt, bool reset) { MachineState *machine = MACHINE(spapr); SpaprMachineClass *smc = SPAPR_MACHINE_GET_CLASS(machine); - uint8_t rng_seed[32]; int chosen; _FDT(chosen = fdt_add_subnode(fdt, 0, "chosen")); @@ -1100,8 +1099,7 @@ static void spapr_dt_chosen(SpaprMachineState *spapr, void *fdt, bool reset) spapr_dt_ov5_platform_support(spapr, fdt, chosen); } - qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed)); - _FDT(fdt_setprop(fdt, chosen, "rng-seed", rng_seed, sizeof(rng_seed))); + _FDT(fdt_setprop(fdt, chosen, "rng-seed", spapr->fdt_rng_seed, 32)); _FDT(spapr_dt_ovec(fdt, chosen, spapr->ov5_cas, "ibm,architecture-vec-5")); } @@ -1654,6 +1652,14 @@ static void spapr_machine_reset(MachineState *machine, ShutdownCause reason) void *fdt; int rc; + if (reason != SHUTDOWN_CAUSE_SNAPSHOT_LOAD) { + /* + * Record-replay snapshot load must not consume random, this was + * already replayed from initial machine reset. + */ + qemu_guest_getrandom_nofail(spapr->fdt_rng_seed, 32); + } + pef_kvm_reset(machine->cgs, &error_fatal); spapr_caps_apply(spapr);