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 3D770D12D4C for ; Wed, 3 Dec 2025 11:47:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8D79B10E778; Wed, 3 Dec 2025 11:47:43 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="f9mlpCoY"; dkim-atps=neutral Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9401E10E778 for ; Wed, 3 Dec 2025 11:47:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1764762461; bh=l1brxEcZEA0OgRbkgRwjthl5cw9jv+wS/NkiJhQwLE0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=f9mlpCoYxuvF1RhDsSx/P4LQ0tjviho15e1R+U7MuNlo6w8zzuQ+9MkiDESdz/o4q t4bwNcwjs0ISRbT3bn+nzmNZCe7qj4Ru53TbAQ4SUdHwYdGP8VKktbR09XpXhO7shA o7LoDKUmAYoHbSu1YR1HKUI2kANb5lqM/Mr9ISTGO4qYSSwP1O2z9rRMf7D4YMmTTH tSs2WaD+opmj89T7C6124APQYqxWcaurHD/7ukAYiR8buMKOAXzEo3HsOGNzu3oXGz ttC+3SLL3knJjRQvHrmEQAO0to9Npw8OO/sA256DDwtmi5SkGPoTDJJ5ZC1bY+B1Jh ByII+xJq6P8JA== Received: from fedora (unknown [IPv6:2a01:e0a:2c:6930:d919:a6e:5ea1:8a9f]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id 9D48C17E0117; Wed, 3 Dec 2025 12:47:40 +0100 (CET) Date: Wed, 3 Dec 2025 12:47:35 +0100 From: Boris Brezillon To: Boris Brezillon , Steven Price , Liviu Dudau , =?UTF-8?B?QWRy?= =?UTF-8?B?acOhbg==?= Larumbe Cc: dri-devel@lists.freedesktop.org, Akash Goel , Chia-I Wu , kernel@collabora.com Subject: Re: [PATCH v2 3/3] drm/panthor: Unlock the locked region before disabling an AS Message-ID: <20251203124735.61e7af54@fedora> In-Reply-To: <20251203110527.367089-4-boris.brezillon@collabora.com> References: <20251203110527.367089-1-boris.brezillon@collabora.com> <20251203110527.367089-4-boris.brezillon@collabora.com> Organization: Collabora X-Mailer: Claws Mail 4.3.1 (GTK 3.24.51; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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 Wed, 3 Dec 2025 12:05:27 +0100 Boris Brezillon wrote: > An AS can be disabled in the middle of a VM operation (VM being > evicted from an AS slot, for instance). In that case, we need the > locked section to be unlocked before releasing the slot. > > v2: > - Add an lockdep_assert_held() in panthor_mmu_as_disable() > - Collect R-bs > > Fixes: 6e2d3b3e8589 ("drm/panthor: Add support for atomic page table updates") > Signed-off-by: Boris Brezillon > Reviewed-by: Liviu Dudau > Reviewed-by: Chia-I Wu > --- > drivers/gpu/drm/panthor/panthor_mmu.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c b/drivers/gpu/drm/panthor/panthor_mmu.c > index 3644af1a8e56..493e6428d478 100644 > --- a/drivers/gpu/drm/panthor/panthor_mmu.c > +++ b/drivers/gpu/drm/panthor/panthor_mmu.c > @@ -588,14 +588,27 @@ static int panthor_mmu_as_enable(struct panthor_device *ptdev, u32 as_nr, > static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr, > bool recycle_slot) > { > + struct panthor_vm *vm = ptdev->mmu->as.slots[as_nr].vm; > int ret; > > + lockdep_assert_held(&ptdev->mmu->as.slots_lock); > + > /* Flush+invalidate RW caches, invalidate RO ones. */ > ret = panthor_gpu_flush_caches(ptdev, CACHE_CLEAN | CACHE_INV, > CACHE_CLEAN | CACHE_INV, CACHE_INV); > if (ret) > return ret; > > + if (vm && vm->locked_region.size) { > + /* Unlock the region if there a lock pending. */ > + ret = as_send_cmd_and_wait(ptdev, vm->as.id, AS_COMMAND_UNLOCK); > + if (ret) > + return ret; > + > + vm->locked_region.start = 0; > + vm->locked_region.size = 0; Actually, resetting the locked_region range triggers the WARN_ON()s in the vm_[un]map_pages() path, so I'll get rid of that in v3. > + } > + > /* If the slot is going to be used immediately, don't bother changing > * the config. > */