Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Subject: Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
From: Jason Gunthorpe <jgg@xxxxxxxx>
Date: Wed, 24 Feb 2021 14:46:57 -0400
Cc: Thomas Hellström (Intel) <thomas_os@xxxxxxxxxxxx>, DRI Development <dri-devel@xxxxxxxxxxxxxxxxxxxxx>, Intel Graphics Development <intel-gfx@xxxxxxxxxxxxxxxxxxxxx>, Matthew Wilcox <willy@xxxxxxxxxxxxx>, "moderated list:DMA BUFFER SHARING FRAMEWORK" <linaro-mm-sig@xxxxxxxxxxxxxxxx>, John Stultz <john.stultz@xxxxxxxxxx>, Daniel Vetter <daniel.vetter@xxxxxxxxx>, Suren Baghdasaryan <surenb@xxxxxxxxxx>, Christian König <christian.koenig@xxxxxxx>, "open list:DMA BUFFER SHARING FRAMEWORK" <linux-media@xxxxxxxxxxxxxxx>
In-reply-to: <CAKMK7uHzRb6Q_LgPUrrHn18sorYo7ysTgB+PNE36LDUUsJpHDg@mail.gmail.com>

On Wed, Feb 24, 2021 at 09:45:51AM +0100, Daniel Vetter wrote:

> Hm I figured everyone just uses MAP_SHARED for buffer objects since
> COW really makes absolutely no sense. How would we enforce this?

In RDMA we test

drivers/infiniband/core/ib_core_uverbs.c:       if (!(vma->vm_flags & VM_SHARED))

During mmap to reject use of MAP_PRIVATE on BAR pages.

Jason

Follow-Ups:
- Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
  - From: Christian König

References:
- [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
  - From: Daniel Vetter
- Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
  - From: Thomas Hellström (Intel)
- Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
  - From: Daniel Vetter

Prev by Date: Re: [RFC PATCH v6 02/11] media: v4l2: Extend pixel formats to unify single/multi-planar handling (and more)
Next by Date: Re: [PATCH 03/16] media: i2c: rdacm20: Replace goto with a loop
Previous by thread: Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
Next by thread: Re: [Linaro-mm-sig] [PATCH 1/2] dma-buf: Require VM_PFNMAP vma for mmap
Index(es):
- Date
- Thread

[Index of Archives] [Linux Input] [Video for Linux] [Gstreamer Embedded] [Mplayer Users] [Linux USB Devel] [Linux Audio Users] [Linux Kernel] [Linux SCSI] [Yosemite Backpacking]