| Message ID | 1406819797-8372-1-git-send-email-pawel.moll@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Jul 31, 2014 at 04:16:37PM +0100, Pawel Moll wrote: > The bitfield allocation function returns error condition > as a negative value, but in two cases its result > was assigned to an unsigned member of the hw_perf_event > structure, thus the error would not be ever detected. > > Fixed by using an intermediate, signed variable. > > Reported-by: Dan Carpenter <dan.carpenter@oracle.com> > Signed-off-by: Pawel Moll <pawel.moll@arm.com> > --- > > Dan discovered the problem using his static checker. Thanks, Dan! > > Arnd, would you pick up the patch as it is or do you want me > to send a pull request for a "ccn/fixes" branch? I've started to prefer applying patches for cases like these, single-patch pull requests are actually more work than doing that. So: applied on top of next/drivers, where the CCN driver was merged as well. Thanks! -Olof
diff --git a/drivers/bus/arm-ccn.c b/drivers/bus/arm-ccn.c index 4f86bbb..3266f8f 100644 --- a/drivers/bus/arm-ccn.c +++ b/drivers/bus/arm-ccn.c @@ -591,7 +591,7 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) struct arm_ccn *ccn; struct hw_perf_event *hw = &event->hw; u32 node_xp, type, event_id; - int valid; + int valid, bit; struct arm_ccn_component *source; int i; @@ -713,17 +713,18 @@ static int arm_ccn_pmu_event_init(struct perf_event *event) /* Allocate an event source or a watchpoint */ if (type == CCN_TYPE_XP && event_id == CCN_EVENT_WATCHPOINT) - hw->config_base = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask, + bit = arm_ccn_pmu_alloc_bit(source->xp.dt_cmp_mask, CCN_NUM_XP_WATCHPOINTS); else - hw->config_base = arm_ccn_pmu_alloc_bit(source->pmu_events_mask, + bit = arm_ccn_pmu_alloc_bit(source->pmu_events_mask, CCN_NUM_PMU_EVENTS); - if (hw->config_base < 0) { + if (bit < 0) { dev_warn(ccn->dev, "No more event sources/watchpoints on node/XP %d!\n", node_xp); clear_bit(hw->idx, ccn->dt.pmu_counters_mask); return -EAGAIN; } + hw->config_base = bit; ccn->dt.pmu_counters[hw->idx].event = event;
The bitfield allocation function returns error condition as a negative value, but in two cases its result was assigned to an unsigned member of the hw_perf_event structure, thus the error would not be ever detected. Fixed by using an intermediate, signed variable. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Pawel Moll <pawel.moll@arm.com> --- Dan discovered the problem using his static checker. Thanks, Dan! Arnd, would you pick up the patch as it is or do you want me to send a pull request for a "ccn/fixes" branch? drivers/bus/arm-ccn.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)