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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-12 16:16:29 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-12 16:16:29 -0800 |
| commit | a0e5056e3b733ecb7d3089f8e1e6529525490ab9 (patch) | |
| tree | badb1c482b291cd942e8c7955246f8b044e900bb | |
| parent | f2ea97cbae25af2ec2ccfe892211c39147a8b4dc (diff) | |
| parent | d911e03d097bdc01363df5d81c43f69432eb785c (diff) | |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux into akpm
Pull s390 regression fix from Martin Schwidefsky:
"The recent fix for the s390 sched_clock() function uncovered yet
another bug in s390_next_ktime which causes an endless loop in KVM.
This regression should be fixed before v3.8.
I keep the fingers crossed that this is the last one for v3.8."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/timer: avoid overflow when programming clock comparator
| -rw-r--r-- | arch/s390/kernel/time.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index a5f4f5a1d24..0aa98db8a80 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -120,6 +120,9 @@ static int s390_next_ktime(ktime_t expires, nsecs = ktime_to_ns(ktime_add(timespec_to_ktime(ts), expires)); do_div(nsecs, 125); S390_lowcore.clock_comparator = sched_clock_base_cc + (nsecs << 9); + /* Program the maximum value if we have an overflow (== year 2042) */ + if (unlikely(S390_lowcore.clock_comparator < sched_clock_base_cc)) + S390_lowcore.clock_comparator = -1ULL; set_clock_comparator(S390_lowcore.clock_comparator); return 0; } |