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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 7A51FCD6E57 for ; Tue, 2 Jun 2026 07:16:33 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DEF2910EC86; Tue, 2 Jun 2026 07:16:32 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="aNG0beap"; dkim-atps=neutral Received: from mail-ot1-f50.google.com (mail-ot1-f50.google.com [209.85.210.50]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0F43C10EC7B for ; Tue, 2 Jun 2026 07:16:32 +0000 (UTC) Received: by mail-ot1-f50.google.com with SMTP id 46e09a7af769-7e6b571750bso1801686a34.1 for ; Tue, 02 Jun 2026 00:16:31 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1780384591; cv=none; d=google.com; s=arc-20240605; b=bkOsz6F4Zm79TKxUaBZQ8KKPK1X7xEeuObEljYLt0EejAahsyW3x4ZIsLULo18hmv+ /JOKMLa/5BX/bGNCVpzp9WGXSzc1pM4HNFptlWWmBKuTvlehmEBi7AOpX2tRmv/SEqTJ GAxtBhnImizRGRz9oHKd3Lhctk95kJ2yGZnpPREZsV0I2PkJXlNmNruKj0wn6WVKqTNZ n3aVTUNwAEYOfokWVAV+PGE/8tqkiK6XDQZEHkikbssu7WK68JCgbtxO/ivPetYAmK3u zyj2DCTD9wjd3hr+jneqfrBogupEIeA0PCYTL+5R6sao79rQrb/71A7mRy2cVHUEPzbI 4h1Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20240605; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:dkim-signature; bh=6QljEUOAK4GhDaCOum5n6uKCL9G0xte2SQqS3q0iDCI=; fh=hiwIcrYYK/iBogAjt+EAt48QdBjy9n5Z+f4eUoiV4vI=; b=LBTWK1pvAwtjGCmEYrby8HQu44mejptfg6ykwyDQE1iZehr+HVibCl6RyJtie7YbVg umEsao6W65I5LimM9FvzV1S3ZdXbIWaApxtdYCjtvKobFmBTno5c1/LsRoWW0wzdolpZ Ywwc3sq9XoR/Q2DhoIWcrmAe7cp+CAVdg/u7Qrg4/riTJ62GNgS5eNuZuVg3XKvYfD8e i/TLx8Q2cqX5dlgU7aXxQmyvUzSwXdm8atZiejXkv9txmi9aYs/uY/LfLzRDCZ2pXF3p mGC21FA9Q3FLcqMzs/WC058E8ZrR/I8UswVEsqCK7Tc5sP19n3Lpayv8f0qkGJ7Dfzkp g2UQ==; darn=lists.freedesktop.org ARC-Authentication-Results: i=1; mx.google.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1780384591; x=1780989391; darn=lists.freedesktop.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=6QljEUOAK4GhDaCOum5n6uKCL9G0xte2SQqS3q0iDCI=; b=aNG0beapdmeE1Q5MwVIUOGYRJUOKpMeh4DlfFjYdAwhVVF1MChGYxpaIFYOaeYlYzj XDxcufVeF4JWZPFPl107Aw6bOG0EvoJX5KBrJaxN05s1ofTrFqTCn131rKXQM2RU07k1 7ZLEIgXCn+P6IQq5DJz/apv/HBW4cjHWuCUf7HS5RMmhno4SiX41ggMbyf1sSBdDyiQ3 i723M7RKmPme0udyyZ/jsdTKzX2ZS1ACDIeZmU+yGJ/+op1tSL4FxMl9YjOY9EVxE6u0 nIryEejPsH7SaTIh2yQKZxBR3s5XSlZk05YvHY1G96vdTtjW2fyg7gTUPrJtY9tfrXlS Q2fQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780384591; x=1780989391; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=6QljEUOAK4GhDaCOum5n6uKCL9G0xte2SQqS3q0iDCI=; b=oD2soHAXJC9GWcAQ/YHcTrtMsXr2J35TMc8KoSgufS4A7/oQIAppsRg9pjMFKRZvHw bV4pWSM+JSyIHQKPz0CTJorH3lbBqA3s2bZ1kT9bPTnjmJV+i2NHLPBRWMB5hZCJkKEp OAVFNk2fL/DlF8Z7iMliAVu2NYj4VGQ5uxk8yU1s5deX33n7ZwUYdPJwuBZLaLonGGYu GQiwSZV97/ViTBuEXpg7Uu+0m7zFbwr9ekEtjXzAWP7iRnKSJh9hZSo7qXFgmsmNTBcG m1pv7CJxRPwcDr78ICW/dJ0X6fBGI4FpgjvYBvLAjWLo14J8oBnhjgfTQ9NgW5klLHcA n/ww== X-Forwarded-Encrypted: i=1; AFNElJ99LcSFpoT21b3P+kuz0ZcPr0Mlturck1/AiQ4T5I/REgY75PEE/ikCW34Va1k2bjwn7BQncZQcxtE=@lists.freedesktop.org X-Gm-Message-State: AOJu0YwF1F+5tJkToSO9kMNJx2J5sg3FLQWPg7nUFZiyTsWxLi7XRsj6 s077ne9h/N7z4i2xV4xpPxZWxmKttRv9m5d5FBA0703YXhHxqmnUtaAXDpBWUezxaR47F/Hyf3w 6fkaqHdi3WjaOkZlBUwWRmLjKfmwMk0s= X-Gm-Gg: Acq92OGygDNffX3vIOYfRfwgFN5hPIxytbGX8wnupj59qyBKtMbLr6Ez6g39fnW5aCQ 5Usayq30StKIP04AShLGIV9fT5lPAzmbhrRIvzGKagtT5KImVCOPPpHSqUIZJgntTgNZvlgdDkS 3bCpCNbBl86DF2bzNd748kaTfiqYzKrpz260rVfZiSdvi0dbOm0CrlQPJeqBnOb8yvqaMXKU7Zl noJD24XeEYjzox/hoRtiO/ykKCT5zyyQcb8wo+Qereg3h9U+uXm/hGrcGx+pO62pvceX79rMv1G 9WC1mmLbMOr7RlEIE4mt X-Received: by 2002:a05:6830:4194:b0:7e5:68d0:462d with SMTP id 46e09a7af769-7e6a1e20025mr8818586a34.19.1780384591168; Tue, 02 Jun 2026 00:16:31 -0700 (PDT) MIME-Version: 1.0 References: <20260601-lima-alloc-fix-v1-1-16d3f3b7b780@axis.com> In-Reply-To: <20260601-lima-alloc-fix-v1-1-16d3f3b7b780@axis.com> From: Qiang Yu Date: Tue, 2 Jun 2026 15:16:19 +0800 X-Gm-Features: AVHnY4JMWdde9M5jvz91Ix9Ornc_9nS90uFwDWQRw6lHLBiqcEwZUx95HD6BJaU Message-ID: Subject: Re: [PATCH] drm/lima: call drm_mm_init() with a valid allocation range To: Henrik Grimler Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Eric Anholt , Erico Nunes , Marek Vasut , Neil Armstrong , Andreas Baierl , Marek Szyprowski , Rob Herring , dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, lima@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel@axis.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Jun 1, 2026 at 8:04=E2=80=AFPM Henrik Grimler wrote: > > lima_vm_create() is currently run before va_start and va_end are set up, > meaning they are both 0. lima_vm_create() runs drm_mm_init() with them > as arguments for the allocator, and if DRM_DEBUG_MM is enabled the > DRM_MM_BUG_ON check in drm_mm_init then fires, as seen here on > exynos4412-odroid-u2: > > [ 1.736297] ------------[ cut here ]------------ > [ 1.740370] kernel BUG at drivers/gpu/drm/drm_mm.c:931! > [ 1.745574] Internal error: Oops - BUG: 0 [#1] SMP ARM > [ 1.750697] Modules linked in: > [ 1.753734] CPU: 0 UID: 0 PID: 41 Comm: kworker/u16:1 Not tainted 7.0.= 10-postmarketos-exynos4 #11 PREEMPT > [ 1.763372] Hardware name: Samsung Exynos (Flattened Device Tree) > [ 1.769446] Workqueue: events_unbound deferred_probe_work_func > [ 1.775261] PC is at drm_mm_init+0x9c/0xa4 > [ 1.779339] LR is at lima_vm_create+0x144/0x17c > [ ... ] > > Fix the issue by moving the lima_vm_create() call after va_start and > va_end are set up. > > Fixes: a1d2a6339961 ("drm/lima: driver for ARM Mali4xx GPUs") > Signed-off-by: Henrik Grimler > --- > This is a low priority fix and can wait for v7.2, it does not cause > any real issues as far as I have seen: drm_mm_init() is re-run some > seconds after first run with correct parameters. Reviewed-by: Qiang Yu drm mm in the empty_vm is not used at all, so no issue caused by it. drm mm of a real per app vm matters but they are initialized properly after va_start/end set. In fact only the PDE page matters in empty_vm, I should only create it instead of the full lima_vm. > --- > drivers/gpu/drm/lima/lima_device.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/lima/lima_device.c b/drivers/gpu/drm/lima/li= ma_device.c > index 0bf7105c8748..7c873e62c16d 100644 > --- a/drivers/gpu/drm/lima/lima_device.c > +++ b/drivers/gpu/drm/lima/lima_device.c > @@ -368,12 +368,6 @@ int lima_device_init(struct lima_device *ldev) > if (err) > goto err_out0; > > - ldev->empty_vm =3D lima_vm_create(ldev); > - if (!ldev->empty_vm) { > - err =3D -ENOMEM; > - goto err_out1; > - } > - > ldev->va_start =3D 0; > if (ldev->id =3D=3D lima_gpu_mali450) { > ldev->va_end =3D LIMA_VA_RESERVE_START; > @@ -387,6 +381,12 @@ int lima_device_init(struct lima_device *ldev) > } else > ldev->va_end =3D LIMA_VA_RESERVE_END; > > + ldev->empty_vm =3D lima_vm_create(ldev); > + if (!ldev->empty_vm) { > + err =3D -ENOMEM; > + goto err_out1; > + } > + > ldev->iomem =3D devm_platform_ioremap_resource(pdev, 0); > if (IS_ERR(ldev->iomem)) { > dev_err(ldev->dev, "fail to ioremap iomem\n"); > > --- > base-commit: c453c60fdba437f69209e027b418c4a24143605a > change-id: 20260529-lima-alloc-fix-2cd5408f6493 > > Best regards, > -- > Henrik Grimler >