Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-24 Thread Daniel Vetter
On Fri, Nov 20, 2020 at 09:23:12PM +0900, Tomasz Figa wrote: > On Fri, Nov 20, 2020 at 9:08 PM Hans Verkuil wrote: > > > > On 20/11/2020 11:51, Daniel Vetter wrote: > > > On Fri, Nov 20, 2020 at 11:39 AM Hans Verkuil wrote: > > >> > > >> On 20/11/2020 10:18, Daniel Vetter wrote: > > >>> On Fri,

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Tomasz Figa
On Fri, Nov 20, 2020 at 9:08 PM Hans Verkuil wrote: > > On 20/11/2020 11:51, Daniel Vetter wrote: > > On Fri, Nov 20, 2020 at 11:39 AM Hans Verkuil wrote: > >> > >> On 20/11/2020 10:18, Daniel Vetter wrote: > >>> On Fri, Nov 20, 2020 at 9:28 AM Hans Verkuil wrote: > > On 20/11/2020

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Hans Verkuil
On 20/11/2020 11:51, Daniel Vetter wrote: > On Fri, Nov 20, 2020 at 11:39 AM Hans Verkuil wrote: >> >> On 20/11/2020 10:18, Daniel Vetter wrote: >>> On Fri, Nov 20, 2020 at 9:28 AM Hans Verkuil wrote: On 20/11/2020 09:06, Hans Verkuil wrote: > On 19/11/2020 15:41, Daniel Vetter

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Daniel Vetter
On Fri, Nov 20, 2020 at 11:39 AM Hans Verkuil wrote: > > On 20/11/2020 10:18, Daniel Vetter wrote: > > On Fri, Nov 20, 2020 at 9:28 AM Hans Verkuil wrote: > >> > >> On 20/11/2020 09:06, Hans Verkuil wrote: > >>> On 19/11/2020 15:41, Daniel Vetter wrote: > The media model assumes that

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Hans Verkuil
On 20/11/2020 10:18, Daniel Vetter wrote: > On Fri, Nov 20, 2020 at 9:28 AM Hans Verkuil wrote: >> >> On 20/11/2020 09:06, Hans Verkuil wrote: >>> On 19/11/2020 15:41, Daniel Vetter wrote: The media model assumes that buffers are all preallocated, so that when a media pipeline is

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Daniel Vetter
On Fri, Nov 20, 2020 at 9:28 AM Hans Verkuil wrote: > > On 20/11/2020 09:06, Hans Verkuil wrote: > > On 19/11/2020 15:41, Daniel Vetter wrote: > >> The media model assumes that buffers are all preallocated, so that > >> when a media pipeline is running we never miss a deadline because the > >>

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Tomasz Figa
On Fri, Nov 20, 2020 at 5:28 PM Hans Verkuil wrote: > > On 20/11/2020 09:06, Hans Verkuil wrote: > > On 19/11/2020 15:41, Daniel Vetter wrote: > >> The media model assumes that buffers are all preallocated, so that > >> when a media pipeline is running we never miss a deadline because the > >>

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Hans Verkuil
On 20/11/2020 09:06, Hans Verkuil wrote: > On 19/11/2020 15:41, Daniel Vetter wrote: >> The media model assumes that buffers are all preallocated, so that >> when a media pipeline is running we never miss a deadline because the >> buffers aren't allocated or available. >> >> This means we cannot

Re: [PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-20 Thread Hans Verkuil
On 19/11/2020 15:41, Daniel Vetter wrote: > The media model assumes that buffers are all preallocated, so that > when a media pipeline is running we never miss a deadline because the > buffers aren't allocated or available. > > This means we cannot fix the v4l follow_pfn usage through >

[PATCH v6 09/17] media/videbuf1|2: Mark follow_pfn usage as unsafe

2020-11-19 Thread Daniel Vetter
The media model assumes that buffers are all preallocated, so that when a media pipeline is running we never miss a deadline because the buffers aren't allocated or available. This means we cannot fix the v4l follow_pfn usage through mmu_notifier, without breaking how this all works. The only