On Tue, Jan 21, 2020 at 11:22 AM Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote: > > On Mo, 2020-01-20 at 19:47 +0100, Arnd Bergmann wrote: > > On Mon, Jan 20, 2020 at 6:48 PM Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote: > > > On Fr, 2020-01-17 at 16:47 +0100, Guido Günther wrote: > > > > This breaks rendering here on arm64/gc7000 due to > > > > > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_PREP or DRM_IOCTL_MSM_GEM_CPU_PREP, 0xfffff7888680) = -1 EINVAL (Invalid argument) > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_FINI or DRM_IOCTL_QXL_CLIENTCAP, 0xfffff78885e0) = 0 > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_PREP or DRM_IOCTL_MSM_GEM_CPU_PREP, 0xfffff7888680) = -1 EINVAL (Invalid argument) > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_FINI or DRM_IOCTL_QXL_CLIENTCAP, 0xfffff78885e0) = 0 > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_PREP or DRM_IOCTL_MSM_GEM_CPU_PREP, 0xfffff7888680) = -1 EINVAL (Invalid argument) > > > > ioctl(6, DRM_IOCTL_ETNAVIV_GEM_CPU_FINI or DRM_IOCTL_QXL_CLIENTCAP, 0xfffff78885e0) = 0 > > > > > > > > This is due to > > > > > > > > get_abs_timeout(&req.timeout, 5000000000); > > > > > > > > in etna_bo_cpu_prep which can exceed NSEC_PER_SEC. > > > > > > > > Should i send a patch to revert that change since it breaks existing userspace? > > > > > > No need to revert. This patch has not been applied to the etnaviv tree > > > yet, I guess it's just in one of Arnds branches feeding into -next. > > > > > > That part of userspace is pretty dumb, as it misses to renormalize > > > tv_nsec when it overflows the second boundary. So if what I see is > > > correct it should be enough to allow 2 * NSEC_PER_SEC, which should > > > both reject broken large timeout and keep existing userspace working. > > > > Ah, so it's never more than 2 billion nanoseconds in known user space? > > I can definitely change my patch (actually add one on top) to allow that > > and handle it as before, or alternatively accept any 64-bit nanosecond value > > as arm64 already did, but make it less inefficient to handle. > > So the broken userspace code looks like this: > > static inline void get_abs_timeout(struct drm_etnaviv_timespec *tv, uint64_t ns) > { > struct timespec t; > uint32_t s = ns / 1000000000; > clock_gettime(CLOCK_MONOTONIC, &t); > tv->tv_sec = t.tv_sec + s; > tv->tv_nsec = t.tv_nsec + ns - (s * 1000000000); > } > > Which means it _tries_ to do the right thing by putting the billion > part into the tv_sec member and only the remaining ns part is added to > tv_nsec, but then it fails to propagate a tv_nsec overflow over > NSEC_PER_SEC into tv_sec. > > Which means the tv_nsec should never be more than 2 * NSEC_PER_SEC in > known userspace. I would prefer if we could make the interface as > strict as possible (i.e. no arbitrary large numbers in tv_nsec), while > keeping this specific corner case working. I've added a patch on top of my 2038 branch, please have a look at that. Arnd _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel