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 C8FFFCAC5AC for ; Tue, 23 Sep 2025 19:35:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F0C8B10E198; Tue, 23 Sep 2025 19:35:38 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=linaro.org header.i=@linaro.org header.b="s28hwR+u"; dkim-atps=neutral Received: from mail-ed1-f67.google.com (mail-ed1-f67.google.com [209.85.208.67]) by gabe.freedesktop.org (Postfix) with ESMTPS id CFBF710E198 for ; Tue, 23 Sep 2025 19:35:37 +0000 (UTC) Received: by mail-ed1-f67.google.com with SMTP id 4fb4d7f45d1cf-62f4a8dfadcso7182064a12.1 for ; Tue, 23 Sep 2025 12:35:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1758656136; x=1759260936; darn=lists.freedesktop.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=qdwjSx6yqDrwznedzComO+rifSLut17oWkmQ13N72Tc=; b=s28hwR+umgUiSCuflwtPbUwxBVYdhEbcjoem6EWF9T9HX1T5T5KLISxflpl0HeOIT0 p9oN0dqq52sCJPBaFerqa8HTZhicdaQb+coILTRwW9rSZ5UxrHWG4SPthSQ4O/HVAvJu ff+gErKsXb9dWN5bSp9i9nDne8D19S/gyg6SoWL7uP+OtcRkbulpZWXGopotXKhPPkTD ZIM+aHSoQ8GSW4Zw4NE4B8cLpCqbprH/cvMalJDHR3vCn5PYH3o1AhRpSVc/53ixlE3H lB2WWOGeFJJBQN1RORJck9CAFbIxhDt01lk9qntXtgQEV2sTgVyjkC8VGU3fSRaw/DU9 wqYA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758656136; x=1759260936; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=qdwjSx6yqDrwznedzComO+rifSLut17oWkmQ13N72Tc=; b=vK8f3ZCA1h4NLBWGhQkWm+NWaLQVGeLPcgDMOmALYtJdJz+164B2/tID35cPI8IWic MvfLyQO8UyPQxlMUUwJtoAWH0XmoVArFKd1wipdP7YwxPMQTC2AbqYvpy94EgNWnZUE9 uLXn//qsQRuq4tKeEaXdYdcI5VwIhCcaKTNEbrmbKgn6AC1MUCnxsIwpQtlvwd4xUMqb iDxdVPc4yRcV3C+uehco8VSYzaazq+P2NKPVZYU4bRb9mW0q/NjPay1uRSo9Ln2hmiWF 92XDgIYBhHdO0GS6GSqwxLKrfCGBNXUa1KtXxe/KzOIvqaPIK9HZYPGkE3BclnwDvNqz m+UQ== X-Gm-Message-State: AOJu0YyFAZ4OGOwKw7a9Q8wPc19qTGzMiZEOfZACwBuas31M1zPsM4ZM MLXDp4ahOA3yoW/GLDXjksUuui8mQZZZT7AToKNEW9vj4kjeVHIVUFprmT6H/6kvP20= X-Gm-Gg: ASbGncu0WyjGnlozF+tGl+TqmVu7czJtlxDaT9YH32Gc5wuTYsnH/eAjW+BCM4e9lle t1CZej3wViDMexjTT2jwMmmO/v82pM38rSZc8MGIO1kypnFGmvlTxPTL8v2ICYNSNYvibz9Wx9J UUd9FoR4gcdXNyOrlK0PTM2ziB7JHt+CIg4+G6LP1/rEkaJzApseFi1jIAkeROBNUCTa/DfNKZP G3boYi/o+ZkHve/39QpoW2ldysANoPlE4pjUCqaHzf2Up0CmeimAkjD/gG5YBu+iEA/6l/wMHDH daF44J071GlUEDy9GukErk/OTCX94vi8u+yymq1dV4V4MJPYeTwmTmGp3KUoBr3Do2MM+wVedMJ z0NsiahTSUVF6FP6Kw1pq2VhRWvWdrnEl X-Google-Smtp-Source: AGHT+IGlCvK6yuqIUQUFOgGwHK0uqqneA6mTN1hmeGJkoLmdyjKHvGizIk+emNFkQbBfTqMzUbXl5A== X-Received: by 2002:a17:907:d25:b0:b0e:8cd4:e2d3 with SMTP id a640c23a62f3a-b302705ebc2mr337045066b.19.1758656136185; Tue, 23 Sep 2025 12:35:36 -0700 (PDT) Received: from linaro.org ([2a02:2454:ff21:30:bd4e:c20d:5910:982f]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-b27217f616esm995766666b.72.2025.09.23.12.35.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Sep 2025 12:35:35 -0700 (PDT) Date: Tue, 23 Sep 2025 21:35:31 +0200 From: Stephan Gerhold To: Rob Clark Cc: dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten , David Airlie , Simona Vetter , open list Subject: Re: [PATCH] drm/msm: Fix GEM free for imported dma-bufs Message-ID: References: <20250923140441.746081-1-robin.clark@oss.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250923140441.746081-1-robin.clark@oss.qualcomm.com> 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 Tue, Sep 23, 2025 at 07:04:40AM -0700, Rob Clark wrote: > Imported dma-bufs also have obj->resv != &obj->_resv. So we should > check both this condition in addition to flags for handling the > _NO_SHARE case. > > Fixes this splat that was reported with IRIS video playback: > > ------------[ cut here ]------------ > WARNING: CPU: 3 PID: 2040 at drivers/gpu/drm/msm/msm_gem.c:1127 msm_gem_free_object+0x1f8/0x264 [msm] > CPU: 3 UID: 1000 PID: 2040 Comm: .gnome-shell-wr Not tainted 6.17.0-rc7 #1 PREEMPT > pstate: 81400005 (Nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) > pc : msm_gem_free_object+0x1f8/0x264 [msm] > lr : msm_gem_free_object+0x138/0x264 [msm] > sp : ffff800092a1bb30 > x29: ffff800092a1bb80 x28: ffff800092a1bce8 x27: ffffbc702dbdbe08 > x26: 0000000000000008 x25: 0000000000000009 x24: 00000000000000a6 > x23: ffff00083c72f850 x22: ffff00083c72f868 x21: ffff00087e69f200 > x20: ffff00087e69f330 x19: ffff00084d157ae0 x18: 0000000000000000 > x17: 0000000000000000 x16: ffffbc704bd46b80 x15: 0000ffffd0959540 > x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 > x11: ffffbc702e6cdb48 x10: 0000000000000000 x9 : 000000000000003f > x8 : ffff800092a1ba90 x7 : 0000000000000000 x6 : 0000000000000020 > x5 : ffffbc704bd46c40 x4 : fffffdffe102cf60 x3 : 0000000000400032 > x2 : 0000000000020000 x1 : ffff00087e6978e8 x0 : ffff00087e6977e8 > Call trace: > msm_gem_free_object+0x1f8/0x264 [msm] (P) > drm_gem_object_free+0x1c/0x30 [drm] > drm_gem_object_handle_put_unlocked+0x138/0x150 [drm] > drm_gem_object_release_handle+0x5c/0xcc [drm] > drm_gem_handle_delete+0x68/0xbc [drm] > drm_gem_close_ioctl+0x34/0x40 [drm] > drm_ioctl_kernel+0xc0/0x130 [drm] > drm_ioctl+0x360/0x4e0 [drm] > __arm64_sys_ioctl+0xac/0x104 > invoke_syscall+0x48/0x104 > el0_svc_common.constprop.0+0x40/0xe0 > do_el0_svc+0x1c/0x28 > el0_svc+0x34/0xec > el0t_64_sync_handler+0xa0/0xe4 > el0t_64_sync+0x198/0x19c > ---[ end trace 0000000000000000 ]--- > ------------[ cut here ]------------ > > Reported-by: Stephan Gerhold Tested-by: Stephan Gerhold Perhaps also add Closes: https://lore.kernel.org/r/aNF6N8u1VIFSTaRM@linaro.org/ when applying. Thanks! Stephan > Fixes: de651b6e040b ("drm/msm: Fix refcnt underflow in error path") > Signed-off-by: Rob Clark > --- > drivers/gpu/drm/msm/msm_gem.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c > index 9f0f5b77f1bd..3aea9b493375 100644 > --- a/drivers/gpu/drm/msm/msm_gem.c > +++ b/drivers/gpu/drm/msm/msm_gem.c > @@ -1121,12 +1121,16 @@ static void msm_gem_free_object(struct drm_gem_object *obj) > put_pages(obj); > } > > - if (obj->resv != &obj->_resv) { > + /* > + * In error paths, we could end up here before msm_gem_new_handle() > + * has changed obj->resv to point to the shared resv. In this case, > + * we don't want to drop a ref to the shared r_obj that we haven't > + * taken yet. > + */ > + if ((msm_obj->flags & MSM_BO_NO_SHARE) && (obj->resv != &obj->_resv)) { > struct drm_gem_object *r_obj = > container_of(obj->resv, struct drm_gem_object, _resv); > > - WARN_ON(!(msm_obj->flags & MSM_BO_NO_SHARE)); > - > /* Drop reference we hold to shared resv obj: */ > drm_gem_object_put(r_obj); > } > -- > 2.51.0 >