From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A40A126B092; Mon, 14 Apr 2025 09:50:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744624213; cv=none; b=o2iEkPTycqMzTduV3rTq/TbzcV1/BFFzgz8vVxqcAk0TfWmJJfXO5m5Ead6j6laLuyYyKSr6hs+SBayjQCEwrUb8ub17Yc4d+h3GElPw+qacrjd1VMNtvvA6G2I4kxQo41HDkh95e4mpMI9p4dh1K274HwkFXRNeqnwRhBxPc8k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744624213; c=relaxed/simple; bh=pzAVg/gEqz48XW9Y34vG1o5PUtXkZR8QjIF6M24lUqw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ZlO6JNRLTsf4CICViRgHh/tezsblrFxeIQQAbfh8l4L70fRHrMj/AUtQVaty3rVD8/Fxqokpsjcb/IL70DwnhTH7Yi/nutqLkNrzStYeUQ/3YaTHOO8Tgkj/1DlL4k49ZB7PiBQRTEQZIWtZpIXIhlVjoxGnwxfxbH94S8qc5wU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 491921007; Mon, 14 Apr 2025 02:50:07 -0700 (PDT) Received: from [10.57.87.24] (unknown [10.57.87.24]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 098953F66E; Mon, 14 Apr 2025 02:50:04 -0700 (PDT) Message-ID: <93a4ec41-3bd8-4485-a4fe-d0def3509b79@arm.com> Date: Mon, 14 Apr 2025 10:50:02 +0100 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 1/4] drm/panthor: Introduce BO labeling To: =?UTF-8?Q?Adri=C3=A1n_Larumbe?= , "To : Boris Brezillon" , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Sumit Semwal , =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: kernel@collabora.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org References: <20250411150357.3308921-1-adrian.larumbe@collabora.com> <20250411150357.3308921-2-adrian.larumbe@collabora.com> From: Steven Price Content-Language: en-GB In-Reply-To: <20250411150357.3308921-2-adrian.larumbe@collabora.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Adrián, On 11/04/2025 16:03, Adrián Larumbe wrote: > Add a new character string Panthor BO field, and a function that allows > setting it from within the driver. > > Driver takes care of freeing the string when it's replaced or no longer > needed at object destruction time, but allocating it is the responsibility > of callers. > > Signed-off-by: Adrián Larumbe > Reviewed-by: Boris Brezillon > --- > drivers/gpu/drm/panthor/panthor_gem.c | 39 +++++++++++++++++++++++++++ > drivers/gpu/drm/panthor/panthor_gem.h | 17 ++++++++++++ > 2 files changed, 56 insertions(+) > > diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c > index 8244a4e6c2a2..af0ac17f357f 100644 > --- a/drivers/gpu/drm/panthor/panthor_gem.c > +++ b/drivers/gpu/drm/panthor/panthor_gem.c > @@ -2,6 +2,7 @@ > /* Copyright 2019 Linaro, Ltd, Rob Herring */ > /* Copyright 2023 Collabora ltd. */ > > +#include > #include > #include > #include > @@ -18,6 +19,14 @@ static void panthor_gem_free_object(struct drm_gem_object *obj) > struct panthor_gem_object *bo = to_panthor_bo(obj); > struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem; > > + /* > + * Label might have been allocated with kstrdup_const(), > + * we need to take that into account when freeing the memory > + */ > + kfree_const(bo->label.str); > + > + mutex_destroy(&bo->label.lock); > + > drm_gem_free_mmap_offset(&bo->base.base); > mutex_destroy(&bo->gpuva_list_lock); > drm_gem_shmem_free(&bo->base); > @@ -196,6 +205,7 @@ struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t > obj->base.map_wc = !ptdev->coherent; > mutex_init(&obj->gpuva_list_lock); > drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock); > + mutex_init(&obj->label.lock); > > return &obj->base.base; > } > @@ -247,3 +257,32 @@ panthor_gem_create_with_handle(struct drm_file *file, > > return ret; > } > + > +void > +panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label) > +{ > + struct panthor_gem_object *bo = to_panthor_bo(obj); > + const char *old_label; > + > + scoped_guard(mutex, &bo->label.lock) { > + old_label = bo->label.str; > + bo->label.str = label; > + } > + > + kfree(old_label); Shouldn't this be kfree_const()? I suspect as things stand we can't trigger this bug but it's inconsistent. > +} > + > +void > +panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label) > +{ > + const char *str; > + > + str = kstrdup_const(label, GFP_KERNEL); > + if (!str) { In the next patch you permit user space to clear the label (args->size==0) which means label==NULL and AFAICT kstrdup_const() will return NULL in this case triggering this warning. Thanks, Steve > + /* Failing to allocate memory for a label isn't a fatal condition */ > + drm_warn(bo->obj->dev, "Not enough memory to allocate BO label"); > + return; > + } > + > + panthor_gem_bo_set_label(bo->obj, str); > +} > diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/panthor/panthor_gem.h > index 1a363bb814f4..af0d77338860 100644 > --- a/drivers/gpu/drm/panthor/panthor_gem.h > +++ b/drivers/gpu/drm/panthor/panthor_gem.h > @@ -46,6 +46,20 @@ struct panthor_gem_object { > > /** @flags: Combination of drm_panthor_bo_flags flags. */ > u32 flags; > + > + /** > + * @label: BO tagging fields. The label can be assigned within the > + * driver itself or through a specific IOCTL. > + */ > + struct { > + /** > + * @label.str: Pointer to NULL-terminated string, > + */ > + const char *str; > + > + /** @lock.str: Protects access to the @label.str field. */ > + struct mutex lock; > + } label; > }; > > /** > @@ -91,6 +105,9 @@ panthor_gem_create_with_handle(struct drm_file *file, > struct panthor_vm *exclusive_vm, > u64 *size, u32 flags, uint32_t *handle); > > +void panthor_gem_bo_set_label(struct drm_gem_object *obj, const char *label); > +void panthor_gem_kernel_bo_set_label(struct panthor_kernel_bo *bo, const char *label); > + > static inline u64 > panthor_kernel_bo_gpuva(struct panthor_kernel_bo *bo) > {