[Intel-gfx] [PATCH v2 4/9] drm/i915/fbdev: lock the fbdev obj before vma pin

[Matt Roper]

On Tue, Feb 21, 2023 at 11:35:02PM -0800, Radhakrishna Sripada wrote:
> From: Tejas Upadhyay <tejas.upadhyay at intel.com>
> 
> lock the fbdev obj before calling into
> i915_vma_pin_iomap(). This helps to solve below :
> 
> <7>[   93.563308] i915 0000:00:02.0: [drm:intelfb_create [i915]] no BIOS fb, allocating a new one
> <4>[   93.581844] ------------[ cut here ]------------
> <4>[   93.581855] WARNING: CPU: 12 PID: 625 at drivers/gpu/drm/i915/gem/i915_gem_pages.c:424 i915_gem_object_pin_map+0x152/0x1c0 [i915]
> 
> Fixes: b473df22760f9 ("backport "drm/i915: Add ww context to intel_dpt_pin, v2.")

This Fixes line isn't correct.  I think you wanted:

Fixes: f0b6b01b3efe ("drm/i915: Add ww context to intel_dpt_pin, v2.")
Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

BTW, your git-sendemail configuration seems to be incorrect; even though
there are Cc's in the body of several of your patches, they're not being
picked up to send copies to the necessary people.


Matt

> Cc: Chris Wilson <chris.p.wilson at intel.com>
> Cc: Matthew Auld <matthew.auld at intel.com>
> Signed-off-by: Tejas Upadhyay <tejas.upadhyay at intel.com>
> Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_fbdev.c | 24 ++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
> index 3659350061a7..2766d7ef0128 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbdev.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
> @@ -210,6 +210,7 @@ static int intelfb_create(struct drm_fb_helper *helper,
>  	bool prealloc = false;
>  	void __iomem *vaddr;
>  	struct drm_i915_gem_object *obj;
> +	struct i915_gem_ww_ctx ww;
>  	int ret;
>  
>  	mutex_lock(&ifbdev->hpd_lock);
> @@ -283,13 +284,24 @@ static int intelfb_create(struct drm_fb_helper *helper,
>  		info->fix.smem_len = vma->size;
>  	}
>  
> -	vaddr = i915_vma_pin_iomap(vma);
> -	if (IS_ERR(vaddr)) {
> -		drm_err(&dev_priv->drm,
> -			"Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
> -		ret = PTR_ERR(vaddr);
> -		goto out_unpin;
> +	for_i915_gem_ww(&ww, ret, false) {
> +		ret = i915_gem_object_lock(vma->obj, &ww);
> +
> +		if (ret)
> +			continue;
> +
> +		vaddr = i915_vma_pin_iomap(vma);
> +		if (IS_ERR(vaddr)) {
> +			drm_err(&dev_priv->drm,
> +					"Failed to remap framebuffer into virtual memory (%pe)\n", vaddr);
> +			ret = PTR_ERR(vaddr);
> +			continue;
> +		}
>  	}
> +
> +	if (ret)
> +		goto out_unpin;
> +
>  	info->screen_base = vaddr;
>  	info->screen_size = vma->size;
>  
> -- 
> 2.34.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation