On Thu, Sep 25, 2014 at 5:32 PM, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > On Sun, Aug 24, 2014 at 4:50 PM, Daniel Kurtz <djkurtz@xxxxxxxxxxxx> wrote: >> Commit [0] stopped setting fix.smem_start and fix.smem_len when creating >> the fbdev. >> >> [0] 2f1eab8d8ab59e799f7d51d62410b398607a7bc3 >> drm/exynos/fbdev: don't set fix.smem/mmio_{start,len} >> >> However, smem_len is used by some userland applications to calculate the >> size for mmap. In particular, it is used by xf86-video-fbdev: >> >> http://cgit.freedesktop.org/xorg/xserver/tree/hw/xfree86/fbdevhw/fbdevhw.c?id=xorg-server-1.15.99.903#n571 >> >> So, let's restore setting the smem_len to unbreak things for these users. >> >> Note: we are still leaving smem_start set to 0. > > Doesn't this cause a system crash when userspace (e.g. fbtest) writes into > the mmap()ed /dev/fb*, as the wrong MMIO region is mapped? Do you see a crash during testing, or is your question hypothetical? I don't think there will be one. exynos's fbev defines its own fb_ops.fb_mmap, which uses dma_mmap_attrs() to mmap the fb's gem buffer, which was allocated by dma_alloc_attrs(). This bypasses the code in drivers/video/fbmem.c:fb_mmap() that references fix.smem_start. But, perhaps I am missing something? -Dan > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel