From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1CBD824EF7E for ; Thu, 3 Apr 2025 14:10:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743689451; cv=pass; b=uSaMIhpniu10ah+NpVOguKlBSIi7aFP5PH/Y06s+Qyw7uMLLvzK4GBYusthNZfehatdA/nf5jVLYsVoMYjcYvaluDdg8nGkEumPyk1d3ZqW1WU3pmngVtNGFzGznUpKRnvcp70tW4k4CRRO2k2NVW5wrySzo/Uw2uBJfDP53P+8= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743689451; c=relaxed/simple; bh=RGDFfVKZ4ZPAC6gitSwYK7UjaaXdpIVN9uER60V8LJc=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=K55W1jUQIwDkEcwoV7X6mvYaH0jPExCkKQyhvBFro2mN5n7WdJH8phuwL06uHTiw+pNpaWSCD0V9KPMutn+huq+NSqve/NOYeikvETkIkk0+ho3NR8Mgh6iydr2aIw7UoZeHbyDleimvnZ1Xs5CQAb4vossp9wJ0EK5DZy+ieQA= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b=JV3g9s1H; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b="JV3g9s1H" ARC-Seal: i=1; a=rsa-sha256; t=1743689419; cv=none; d=zohomail.com; s=zohoarc; b=W4Jl61VITKe2snRKwvixdBP82oOjlVbLaDdhqYDyuFka0qKLRX9KD22vf5pM4iPvZckmdD9udSvj4CCrw3hR/oFBY/sbh49/dHN5NRg6pLWF1qpAdPkFGikCyeAeubUfMHC36TwG15EDmbgUBdq8q2Kjm3rRmRw8T66ONvEDDvE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1743689419; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=lZNR571p4d0dkBSZZRoh4rrvXydvQNaOwh94Ox5SVgo=; b=c5q+lMxj5lwxUqgoFTynziOd3jwmiMfdCjeOcFaep69JLBrot4mJ2UhFEXnVVjMKoGNVXU1McGZ5YrgAUqq2LvncCz9tpSvKDxE84Dze2McG07QuYYy5/PACfpvfrQO4GY4XrmcLZf+/U/3YTwt1OzXYK1WuVEdimVD3y2JTmE8= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=dmitry.osipenko@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1743689419; s=zohomail; d=collabora.com; i=dmitry.osipenko@collabora.com; h=Message-ID:Date:Date:MIME-Version:Subject:Subject:To:To:Cc:Cc:References:From:From:In-Reply-To:Content-Type:Content-Transfer-Encoding:Message-Id:Reply-To; bh=lZNR571p4d0dkBSZZRoh4rrvXydvQNaOwh94Ox5SVgo=; b=JV3g9s1HTX1JqOopmwty0g5Qv76J1FQefHy8W4pbKyaMHIxflrvKo+6mESt9CPp5 3eSjPi16RLOCxw5BGNX0QP87q1/gHRbMY2IitIpaLc9ZjlZnH9zVR0S1fbwaycfUQyK w23O1diPkG7brPe8dYdjVq434pQj2WOKU/0Ddj6M= Received: by mx.zohomail.com with SMTPS id 1743689416979885.2257717900272; Thu, 3 Apr 2025 07:10:16 -0700 (PDT) Message-ID: <91ae764f-d82c-4918-9ce9-0ebbc302c03c@collabora.com> Date: Thu, 3 Apr 2025 17:10:10 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v20 00/10] Add generic DRM-shmem memory shrinker (part 1) To: Thomas Zimmermann , Lucas De Marchi Cc: David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , =?UTF-8?Q?Christian_K=C3=B6nig?= , Gerd Hoffmann , Qiang Yu , Steven Price , Boris Brezillon , Frank Binns , Matt Coster , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel@collabora.com, chaitanya.kumar.borah@intel.com References: <20250322212608.40511-1-dmitry.osipenko@collabora.com> <4a32a492-0ff7-49fc-b208-0ae8b4d2369d@suse.de> From: Dmitry Osipenko Content-Language: en-US In-Reply-To: <4a32a492-0ff7-49fc-b208-0ae8b4d2369d@suse.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ZohoMailClient: External On 4/3/25 10:03, Thomas Zimmermann wrote: > Hi > > Am 03.04.25 um 02:37 schrieb Lucas De Marchi: >> On Sun, Mar 23, 2025 at 12:25:58AM +0300, Dmitry Osipenko wrote: >>> Hi, >>> >>> This a continuation of a year-old series that adds generic DRM-shmem >>> shrinker [1]. The old series became too big with too many patches, more >>> reasonable to split it up into multiple smaller patchsets. Here is >>> the firtst part that makes preparatory DRM changes. >>> >>> [1] https://lore.kernel.org/dri-devel/20240105184624.508603-1- >>> dmitry.osipenko@collabora.com/ >> >> After these patches got merged I started seeing this on ast driver >> and a similar one qemu-cirrus: > > Same here with simpledrm. I wanted to bisect today. I've reproduced using bochs drv, it's the last patch "drm/shmem-helper: Use refcount_t for vmap_use_count" causing the issue. Thanks for the report! This change fixes it, let me send a proper patch: diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 2d924d547a51..554f1d4c1a76 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -416,10 +416,10 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, if (refcount_dec_and_test(&shmem->vmap_use_count)) { vunmap(shmem->vaddr); drm_gem_shmem_unpin_locked(shmem); + + shmem->vaddr = NULL; } } - - shmem->vaddr = NULL; } EXPORT_SYMBOL_GPL(drm_gem_shmem_vunmap_locked); -- Best regards, Dmitry