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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 EB296C433B4 for ; Tue, 18 May 2021 22:20:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C85C8611B0 for ; Tue, 18 May 2021 22:20:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352728AbhERWVd (ORCPT ); Tue, 18 May 2021 18:21:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352722AbhERWVa (ORCPT ); Tue, 18 May 2021 18:21:30 -0400 Received: from mail-lj1-x229.google.com (mail-lj1-x229.google.com [IPv6:2a00:1450:4864:20::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F1934C061573 for ; Tue, 18 May 2021 15:20:10 -0700 (PDT) Received: by mail-lj1-x229.google.com with SMTP id 131so13262520ljj.3 for ; Tue, 18 May 2021 15:20:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=PUf9XT5CCu/J0Hg+9JaJkiWdRUNebcIzPzoiO7Euexs=; b=cojriOorSV9jnlpm7gCjTmIpC1epvLKbDT76cfaCHIptdXb9gsx9TdmRTwg5hj89iP dARDZ9H2Tivs976nEnFnp9wSBdutmcunp0dqJryoPWeLeuvpnB7225Nmrf3GrzNE8JAC f2nnC2vXS1s2P2N78ymYCl8kqGuh/HgAbVaj2ziqXbw4kQEVLFaSLX2xjdXq4svKLy4O wUJdyKti/FOxbOYt/um2BrCJHKZ2sFJYX9n1RAPalWem3r9tSlrfDsFWoMeRnjQ6kk7l HvqKu7lOJHIXEqIg0l+xWSQHmWqgzxRhm16oWfA+n/gy5axoeeff2hUs1pHKWg4NVWm6 RLXg== 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; bh=PUf9XT5CCu/J0Hg+9JaJkiWdRUNebcIzPzoiO7Euexs=; b=aag7kXHUw8W2B6ZEMUwmdcwZpfgEruAeY1UjwQtHCCPAxWSEAIzLJHtsth079+rXA6 Rb8gN28YbR4mBVoDIzj51rzAXVHL3RbOH3PyJUwVg4ds/MhgJL1NmdBMPvpFXg6GDIW+ esu92wr/DyxLW4y/hhD4Dqr9Vx/0e3IQgDdD4FeQY9/97fwUbJC1OimTkelK+t6pxwwa nRuFVgBQrfwjLXSl5qMp8wQBh9/RDk18d8eJ8DeKCdK0vn8EjByXDdKEw+FnoO/D0ATx F1D9/VcWYoT2zfRcUDofZRzkWksqQB5TmOp1PIUwR6b9CpQxk/OVZ8J93UkSCKx4N5+u 1GlQ== X-Gm-Message-State: AOAM5309zQVgUW1wzHRC9e/N990O314pWjQqpz30rTTl1i7vEfypKG4d MBW6sDvcleX/QLV6fuut7/mAB3jA4ibVDasQnFDuhw== X-Google-Smtp-Source: ABdhPJyUn5IvLW+2QdnUKt21vKpBlHrbIQXWm+UgcLTWVmVgXLbnfPFmV9LTAa+69jzgp/D6W+NNGCMLk2wfD2GFsNs= X-Received: by 2002:a2e:90c7:: with SMTP id o7mr5791882ljg.368.1621376409523; Tue, 18 May 2021 15:20:09 -0700 (PDT) MIME-Version: 1.0 References: <20210518120633.GW12395@shell.armlinux.org.uk> In-Reply-To: From: Linus Walleij Date: Wed, 19 May 2021 00:19:58 +0200 Message-ID: Subject: Re: [PATCH 3/4] ARM: change vmalloc_min to vmalloc_start To: "Russell King (Oracle)" , Nicolas Pitre Cc: Yanfei Xu , Mike Rapoport , Ard Biesheuvel , Andrew Morton , Hailong liu , Tian Tao , Linux ARM , linux-kernel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 18, 2021 at 2:15 PM Russell King (Oracle) wrote: > Change the current vmalloc_min, which is supposed to be the lowest > address of vmalloc space including the VMALLOC_OFFSET, to vmalloc_start > which does not include VMALLOC_OFFSET. > > Signed-off-by: Russell King (Oracle) Reviewed-by: Linus Walleij > +static unsigned long __initdata vmalloc_start = VMALLOC_END - (240 << 20); When I first read this it took me some time to figure out what was going on here, so if you have time, please fold in a comment with some explanation of that (240 << 20) thing, in some blog post I described it as "an interesting way to write 0x0f000000" but I suppose commit 0536bdf33faf chose this way for a specific reason? (Paging Nico if he can explain it.) Yours, Linus Walleij 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=-9.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 8AEE0C433ED for ; Tue, 18 May 2021 22:22:27 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 0BF0F60FE6 for ; Tue, 18 May 2021 22:22:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BF0F60FE6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; 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Tue, 18 May 2021 15:20:09 -0700 (PDT) MIME-Version: 1.0 References: <20210518120633.GW12395@shell.armlinux.org.uk> In-Reply-To: From: Linus Walleij Date: Wed, 19 May 2021 00:19:58 +0200 Message-ID: Subject: Re: [PATCH 3/4] ARM: change vmalloc_min to vmalloc_start To: "Russell King (Oracle)" , Nicolas Pitre Cc: Yanfei Xu , Mike Rapoport , Ard Biesheuvel , Andrew Morton , Hailong liu , Tian Tao , Linux ARM , linux-kernel X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210518_152012_114529_857B72FB X-CRM114-Status: GOOD ( 14.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, May 18, 2021 at 2:15 PM Russell King (Oracle) wrote: > Change the current vmalloc_min, which is supposed to be the lowest > address of vmalloc space including the VMALLOC_OFFSET, to vmalloc_start > which does not include VMALLOC_OFFSET. > > Signed-off-by: Russell King (Oracle) Reviewed-by: Linus Walleij > +static unsigned long __initdata vmalloc_start = VMALLOC_END - (240 << 20); When I first read this it took me some time to figure out what was going on here, so if you have time, please fold in a comment with some explanation of that (240 << 20) thing, in some blog post I described it as "an interesting way to write 0x0f000000" but I suppose commit 0536bdf33faf chose this way for a specific reason? (Paging Nico if he can explain it.) Yours, Linus Walleij _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel