linux-kernel - Re: [PATCH v2 4/4] fbdev: vesafb: Cleanup fb_info in .fb

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Date:   Thu, 5 May 2022 15:19:30 +0200
From:   Javier Martinez Canillas <javierm@...hat.com>
To:     linux-kernel@...r.kernel.org, Helge Deller <deller@....de>,
        dri-devel@...ts.freedesktop.org, linux-fbdev@...r.kernel.org
Subject: Re: [PATCH v2 4/4] fbdev: vesafb: Cleanup fb_info in .fb_destroy
 rather than .remove

Hello Daniel,

On 5/5/22 15:02, Daniel Vetter wrote:

[snip]

>>  static void vesafb_destroy(struct fb_info *info)
>>  {
>>  	struct vesafb_par *par = info->par;
>> @@ -187,7 +191,13 @@ static void vesafb_destroy(struct fb_info *info)
>>  	arch_phys_wc_del(par->wc_cookie);
>>  	if (info->screen_base)
>>  		iounmap(info->screen_base);
>> +
>> +	if (((struct vesafb_par *)(info->par))->region)
>> +		release_region(0x3c0, 32);
> 
> This move seems rather iffy, so maybe justify it with "makes the code
> exactly as busted before 27599aacbaef ("fbdev: Hot-unplug firmware fb
> devices on forced removal")"
>

I think that will just drop this change. While being here I wanted the release
order to be the inverse of the order in which the driver acquires them. But I
will only move the framebuffer_release() that is the problematic bit.

Someone if care enough could fix the rest of the driver.
 
> Also same comments as on v1 about adding more details about what/how this
> fixes, with that: Reviewed-by: Daniel Vetter <daniel.vetter@...ll.ch>
>

Yes, I'll do that too. Thanks again for your comments and feedback.

-- 
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat