Will Deacon dbb236c1ce arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW ... Recently vDSO support for CLOCK_MONOTONIC_RAW was added in 49eea433b3 ("arm64: Add support for CLOCK_MONOTONIC_RAW in clock_gettime() vDSO"). Noticing that the core timekeeping code never set tkr_raw.xtime_nsec, the vDSO implementation didn't bother exposing it via the data page and instead took the unshifted tk->raw_time.tv_nsec value which was then immediately shifted left in the vDSO code. Unfortunately, by accellerating the MONOTONIC_RAW clockid, it uncovered potential 1ns time inconsistencies caused by the timekeeping core not handing sub-ns resolution. Now that the core code has been fixed and is actually setting tkr_raw.xtime_nsec, we need to take that into account in the vDSO by adding it to the shifted raw_time value, in order to fix the user-visible inconsistency. Rather than do that at each use (and expand the data page in the process), instead perform the shift/addition operation when populating the data page and remove the shift from the vDSO code entirely. [jstultz: minor whitespace tweak, tried to improve commit message to make it more clear this fixes a regression] Reported-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Daniel Mentz <danielmentz@google.com> Acked-by: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <stephen.boyd@linaro.org> Cc: "stable #4 . 8+" <stable@vger.kernel.org> Cc: Miroslav Lichvar <mlichvar@redhat.com> Link: http://lkml.kernel.org/r/1496965462-20003-4-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>		2017-06-20 10:41:51 +02:00
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.gitignore	arm64: drop non-existing vdso-offsets.h from .gitignore	2017-03-30 19:29:30 +01:00
gen_vdso_offsets.sh	arm64: VDSO support	2012-09-17 13:42:09 +01:00
gettimeofday.S	arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW	2017-06-20 10:41:51 +02:00
Makefile	arm64: fix vdso-offsets.h dependency	2016-07-11 17:10:11 +01:00
note.S	arm64: VDSO support	2012-09-17 13:42:09 +01:00
sigreturn.S	arm64: VDSO support	2012-09-17 13:42:09 +01:00
vdso.lds.S	arm64: vdso: move data page before code pages	2014-07-17 16:18:57 +01:00
vdso.S	arm64: vdso: Mark vDSO code as read-only	2016-02-16 18:20:23 +00:00