Arnd Bergmann 67680d3c04 drm: vblank: use ktime_t instead of timeval ... The drm vblank handling uses 'timeval' to store timestamps in either monotonic or wall-clock time base. In either case, it reads the current time as a ktime_t in get_drm_timestamp() and converts it from there. This is a bit suspicious, as users of 'timeval' often suffer from the time_t overflow in y2038. I have gone through this code and found that it is unlikely to cause problems here: - The user space ABI does not use time_t or timeval, but uses 'u32' and 'long' as the types. This means at least that rebuilding user programs against a new libc with 64-bit time_t does not change the ABI. - As of commit c61eef726a ("drm: add support for monotonic vblank timestamps") in linux-3.8, the monotonic timestamp is the default and can only get reverted to wall-clock through a module-parameter. - With the default monotonic timestamps, there is no problem at all. - The drm_wait_vblank_ioctl() interface is alway safe on 64-bit architectures, on 32-bit it might overflow the 'long' timestamps in 2038 with wall-clock timestamps. - The event handling uses 'u32' seconds, which overflow in 2106 on both 32-bit and 64-bit machines, when wall-clock timestamps are used. - The effect of overflowing either of the two is only temporary (during the overflow, and is likely to keep working again afterwards. It is likely the same problem as observing a 'settimeofday()' call, which was the reason for moving to the monotonic timestamps in the first place. Overall, this seems good enough, so my patch removes the use of 'timeval' from the vblank handling altogether and uses ktime_t consistently, except for the part where we copy the data to user space structures in the existing format. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Sean Paul <seanpaul@chromium.org> Reviewed-by: Keith Packard <keithp@keithp.com> Signed-off-by: Dave Airlie <airlied@redhat.com>		2017-10-13 08:34:46 +10:00
..
acpi	ACPI / bus: Make ACPI_HANDLE() work for non-GPL code again	2017-09-19 22:42:31 +02:00
asm-generic	Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2017-09-14 20:01:41 -07:00
clocksource
crypto
drm	drm: vblank: use ktime_t instead of timeval	2017-10-13 08:34:46 +10:00
dt-bindings	Merge branch '4.14-features' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus	2017-09-15 20:43:33 -07:00
keys	net: rxrpc: Replace time_t type with time64_t type	2017-08-29 10:16:00 +01:00
kvm
linux	2nd batch of v4.15 features:	2017-10-12 10:20:03 +10:00
math-emu
media	media updates for v4.14-rc1	2017-09-07 12:53:14 -07:00
memory
misc
net	net: prevent dst uses after free	2017-09-21 20:42:15 -07:00
pcmcia
ras
rdma	IB: Correct MR length field to be 64-bit	2017-09-25 11:47:23 -04:00
scsi	SCSI misc on 20170913	2017-09-13 10:47:14 -07:00
soc	ARM: SoC driver updates for v4.14	2017-09-10 20:40:00 -07:00
sound	sound updates for 4.14-rc1	2017-09-07 12:44:53 -07:00
target
trace	sched/debug: Add explicit TASK_PARKED printing	2017-09-29 11:02:57 +02:00
uapi	2nd batch of v4.15 features:	2017-10-12 10:20:03 +10:00
video
xen	xen, arm64: drop dummy lookup_address()	2017-09-19 09:25:05 -04:00