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 6F1F8CA0FF0 for ; Mon, 1 Sep 2025 13:31:32 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ut4ck-0007hI-7C; Mon, 01 Sep 2025 09:31:06 -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 1ut4cY-0007Wo-FK for qemu-devel@nongnu.org; Mon, 01 Sep 2025 09:31:03 -0400 Received: from mail-yw1-x112e.google.com ([2607:f8b0:4864:20::112e]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1ut4cU-000238-K3 for qemu-devel@nongnu.org; Mon, 01 Sep 2025 09:30:52 -0400 Received: by mail-yw1-x112e.google.com with SMTP id 00721157ae682-71d6083cc69so36945537b3.2 for ; Mon, 01 Sep 2025 06:30:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1756733447; x=1757338247; darn=nongnu.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=3wewDKBxoOFdqvc7S2uy/Z6NBdCATlYzXKB/aUZXycw=; b=w4A8f9loqfEbJJavg5DEFKucvR0+F0gc9YKrnoDt14kcVq8lz0t79eDDdmhRcMsiNu bfX8sbpIdcnJnULMEM3FDDVWa7k8Lq8lJ7DbCHGGy+6abXu01xkoVxDheV3VELC2MfqG tLcn0oHL9L8knrjaP37IJqfquU8cktD6VA1k36nJYS3fqVPO5zAbe+WsiKX/cD1qokdU +uGModhFXO2pCmIit0/X1LKZfJ+7WAzxkdTR+39DzZ/4tENR7xS+OectAZ3I5FgA9S+Q cl2IX0GPX3lYzLOfGNrssScU+OzrsxlhuYy4IX/MVDHzYMX5BEMVUy2R2hLjwQE+XIvz RcpA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756733447; x=1757338247; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3wewDKBxoOFdqvc7S2uy/Z6NBdCATlYzXKB/aUZXycw=; b=KZMm79NlM/LMS6eNJ5jkbf6OTHnA4EVooRZExRZxOYijYNYH1OJGbpz/QnOOozIcey UU03cuQTPd+FeSA0kzrBel9xVCQQdXPZOSeBmtLM4h9kt8r/sT7bAYx61phmjq3zwD7H ftXjpkMIwnNiure0PmR1NqO9wwc4a7MP1ZxY2hcHDLcRRBE4HAZYJAMdoMz4fAbu/KvU 6BWd1SeUTBA6OB0o+EAHm0hBMNc6WkAPIKr56Txp44SKxAo/uWQem8YrNmH4xfyR0Nlj UwjkbpEZ3F32lcuC4C2eJdy/5T0S+nGNi220FUih8TW1awiiFes4S/lYSejDb31w9RtX PRMw== X-Gm-Message-State: AOJu0Yz9Xp0NIXu+4+judKbPh7vcBIUJy+DFEOwYmD5P5091HSsDUe4p wL0FtcT0K/dshUhzDGIXaQj6dPX5btgOHw1349G6N4xx2RH37y4A0ypCxjb6jFZOXfuYHZJfELn 1Z2lJ7WzeAP9brKyQCqKZo6n+xY0Ev1NUysNlFew8sg== X-Gm-Gg: ASbGncuHWD5UwbjpY4m2xnThzMv0wEVU0+J54UhxO2Qsj/GKYgURoXWRiVfBiUeDprO gy9iJCjYxbIblSnUNbii7HZZHz1l0x+pDP6i+qwu4+2TloAHCSMzXULhAX5N+foQlpRn/MeSUyQ rTLdiVH3+n7wjEIA5Wz/ok84Z329Na7S8ziprTzYHTzJFW0H+YJDGWy9TjXbVMD1OCD2RnkxZGl sFx8FUJ X-Google-Smtp-Source: AGHT+IGzjinj1Be9uhF4e9coeqgVzYuT4x2ZSFoce3lK5RZMIpoiIrsyrN+OSeim8sWHmwNEAkHYp47S9Ww/3rxmKDs= X-Received: by 2002:a05:690c:dcd:b0:721:30a5:3bf1 with SMTP id 00721157ae682-7227636c956mr97919527b3.16.1756733446963; Mon, 01 Sep 2025 06:30:46 -0700 (PDT) MIME-Version: 1.0 References: <20250901132626.28639-1-philmd@linaro.org> <20250901132626.28639-2-philmd@linaro.org> In-Reply-To: <20250901132626.28639-2-philmd@linaro.org> From: Peter Maydell Date: Mon, 1 Sep 2025 14:30:35 +0100 X-Gm-Features: Ac12FXwmkA9tdz4_ZeSzqYzgko3ZQfxuJ-MQJ-B3TXNsqo3Nq-CJMU_3_X1R4CI Message-ID: Subject: Re: [PATCH v2 1/3] target/ppc/kvm: Avoid using alloca() To: =?UTF-8?Q?Philippe_Mathieu=2DDaud=C3=A9?= Cc: qemu-devel@nongnu.org, Paolo Bonzini , qemu-ppc@nongnu.org, Harsh Prateek Bora , Stefan Hajnoczi , Nicholas Piggin , Chinmay Rath , kvm@vger.kernel.org, Glenn Miles , Thomas Huth , =?UTF-8?B?QWxleCBCZW5uw6ll?= , =?UTF-8?Q?Daniel_P=2E_Berrang=C3=A9?= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2607:f8b0:4864:20::112e; envelope-from=peter.maydell@linaro.org; helo=mail-yw1-x112e.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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 On Mon, 1 Sept 2025 at 14:26, Philippe Mathieu-Daud=C3=A9 wrote: > > kvmppc_load_htab_chunk() is used for migration, thus is not > a hot path. Use the heap instead of the stack, removing the > alloca() call. > > Reported-by: Peter Maydell > Signed-off-by: Philippe Mathieu-Daud=C3=A9 > --- > target/ppc/kvm.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c > index d145774b09a..937b9ee986d 100644 > --- a/target/ppc/kvm.c > +++ b/target/ppc/kvm.c > @@ -2760,11 +2760,10 @@ int kvmppc_save_htab(QEMUFile *f, int fd, size_t = bufsize, int64_t max_ns) > int kvmppc_load_htab_chunk(QEMUFile *f, int fd, uint32_t index, > uint16_t n_valid, uint16_t n_invalid, Error *= *errp) > { > - struct kvm_get_htab_header *buf; > size_t chunksize =3D sizeof(*buf) + n_valid * HASH_PTE_SIZE_64; > + g_autofree struct kvm_get_htab_header *buf =3D g_malloc(chunksize); > ssize_t rc; > > - buf =3D alloca(chunksize); > buf->index =3D index; > buf->n_valid =3D n_valid; > buf->n_invalid =3D n_invalid; Reviewed-by: Peter Maydell thanks -- PMM