From: Nathan Lynch <nathan_lynch@mentor.com>
Date: Wed, 5 Feb 2014 05:53:04 +0000 (+0000)
Subject: arm64: vdso: fix coarse clock handling
X-Git-Tag: v3.14-rc2~12^2~7
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=069b918623e1510e58dacf178905a72c3baa3ae4;p=pandora-kernel.git

arm64: vdso: fix coarse clock handling

When __kernel_clock_gettime is called with a CLOCK_MONOTONIC_COARSE or
CLOCK_REALTIME_COARSE clock id, it returns incorrectly to whatever the
caller has placed in x2 ("ret x2" to return from the fast path).  Fix
this by saving x30/LR to x2 only in code that will call
__do_get_tspec, restoring x30 afterward, and using a plain "ret" to
return from the routine.

Also: while the resulting tv_nsec value for CLOCK_REALTIME and
CLOCK_MONOTONIC must be computed using intermediate values that are
left-shifted by cs_shift (x12, set by __do_get_tspec), the results for
coarse clocks should be calculated using unshifted values
(xtime_coarse_nsec is in units of actual nanoseconds).  The current
code shifts intermediate values by x12 unconditionally, but x12 is
uninitialized when servicing a coarse clock.  Fix this by setting x12
to 0 once we know we are dealing with a coarse clock id.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
---

Reading git-diff-tree failed