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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C042AC433E0 for ; Sat, 27 Jun 2020 05:17:39 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 812672081A for ; Sat, 27 Jun 2020 05:17:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Hq5iuHXj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 812672081A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.94) (envelope-from ) id 1jp3DN-0000ZF-RB; Sat, 27 Jun 2020 01:17:21 -0400 Received: from mail-qk1-x744.google.com ([2607:f8b0:4864:20::744]) by shelob.surriel.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1jp3DL-0000Z5-Cy for Kernelnewbies@kernelnewbies.org; Sat, 27 Jun 2020 01:17:19 -0400 Received: by mail-qk1-x744.google.com with SMTP id e11so10838747qkm.3 for ; Fri, 26 Jun 2020 22:17:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=ys7HAM+LOaTIJda6AdL6wGee1jDJR+I814PMk0Lc4F4=; b=Hq5iuHXjsMVELwFlFCF4cZ/lqOvLQazFZP8hqtvcoqOP3qkH7M0AnNz9Ffj7S1a+cD tMmAg1UA4a8XxjNBu+3GIVOngRQKvNghj0XZrGgVBCUay5hOgpa78mVdx72VHHoCqhFD UAFuw1/uSrPlhrcLsZei6QuRNK8BRtgUOfEvL4JQ+76PwjvtILqmUfVOrXP2biIe+SFR 3EATHtLfO9/yYhaihmM4sojaXDvuyHrzq1V7yDfJWMWASgnfUmkfyp1c6UwAM1RROl1i gyZEqPPOOUMNqJCtoVJbCbro8DKfWsvtPR5rOPj3BRNaNH02SDbQw/OQanPUo9JlySf6 tKsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=ys7HAM+LOaTIJda6AdL6wGee1jDJR+I814PMk0Lc4F4=; b=uob2ozO5KGYApzwQeRd5lxjuHm3DfnAtQDbVe2x1uRO16SpHtjKx3TqNp1sjr+DIRL sT7bD73TeHAwS9GmsgH7KaTp4Mfsb5ZkgsC33O1x0pjOUxrYNora6JbphTmv4hcUGefr oWZMjhGOK3Sj9Y/07LOLFJSR6nlk7JeKL51jIjjISEY3Bc8oQj/QDUbzk1vwpvPLdcsg koK+FeGJXbAV1092GkeRiP6MKlWqkq7UGw82KhUXo1j64VmR+j538cPUv2f3USsI3Uhq 3IaZqAWnIujBRMSmLxTuQpcLB16k1OUqfEEb80BV7AItvzDSBoWf1NZ8n4aJQdEhsM16 uF7Q== X-Gm-Message-State: AOAM5314zgepMZAmlPaH2MeZwixHUZK8VmhF+2H8B1KnCETBOZKt3Qj5 GFciIGzHeNgHhD7u+5jrfFsrqFxQYRygRZr5QUiJPZJ6HI3XsQ== X-Google-Smtp-Source: ABdhPJxkWvoDf+mNrM7VbidhLJAyjAUH/r+UMis8LRcE1GX4d5Iu21qA1ylInxAlmn1cHVYrzx8TD8/4/e7dnOzmuPM= X-Received: by 2002:a37:b141:: with SMTP id a62mr4521086qkf.201.1593235036589; Fri, 26 Jun 2020 22:17:16 -0700 (PDT) MIME-Version: 1.0 References: <20200626141319.GC4140284@kroah.com> <67284.1593192143@turing-police> In-Reply-To: <67284.1593192143@turing-police> From: =?UTF-8?B?5a2Z5LiW6b6ZIHN1bnNoaWxvbmc=?= Date: Sat, 27 Jun 2020 13:16:50 +0800 Message-ID: Subject: Re: Are there some potential problems that I should be aware of if I allocate the memory which doesn't have any relation to peripheral hardwares(i.e. DMA, PCI, serial port and etc) by vmalloc() instead of kmalloc()? To: =?UTF-8?Q?Valdis_Kl=C4=93tnieks?= Cc: Greg KH , Kernelnewbies@kernelnewbies.org X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: kernelnewbies-bounces@kernelnewbies.org SGksIFZhbGRpcyBLbMSTdG5pZWtzLEdyZWcgS0gKClRoYW5rcyBhIGxvdCB0byBib3RoIG9mIHlv dS4KCj5BcyBJIG1lbnRpb25lZCBhIGZldyBkYXlzIGFnbywgdGhlIGZhY3QgdGhhdCBhIGhpZ2gt b3JkZXIgYWxsb2NhdGlvbiBmYWlsZWQKPmRvZXMgbm90IG5lY2Vzc2FyaWx5IG1lYW4gYSB0b3Rh bCBmYWlsdXJlLCBhcyBvZnRlbiB0aGUgZHJpdmVyIGNhbiBpbnN0ZWFkCj5hbGxvY2F0ZSBzZXZl cmFsIHNtYWxsZXIgYXJlYXMuClRoZSByZWxhdGVkIGNvZGUgc25pcHBldCBpcyBub3QgdXNlZCBm b3IgYSBkcml2ZXIsIGl0J3MgYSBwYXJ0IG9mIHRoZSByZWFsLXRpbWUKc3lzdGVtLkkgZG9uJ3Qg bW9kaWZ5IHRvbyBtYW55IGNvZGUgc25pcHBldHMgb2YgaXQuCgo+Rmlyc3QsIExpbnV4IGlzIG5v 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