| Message ID | 1406716655-32494-1-git-send-email-punit.agrawal@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 30, 2014 at 11:37:35AM +0100, Punit Agrawal wrote: > From: Himangi Saraogi <himangi774@gmail.com> > > In commit ae91d60ba88ef0bdb1b5e9b2363bd52fc45d2af7, a bug was fixed that > involved converting !x & y to !(x & y). The code below shows the same > pattern, and thus should perhaps be fixed in the same way. > > The Coccinelle semantic patch that makes this change is as follows: > > // <smpl> > @@ expression E1,E2; @@ > ( > !E1 & !E2 > | > - !E1 & E2 > + !(E1 & E2) > ) > // </smpl> > > Cc: stable@vger.kernel.org > Signed-off-by: Himangi Saraogi <himangi774@gmail.com> > Acked-by: Julia Lawall <julia.lawall@lip6.fr> > Acked-by: Punit Agrawal <punit.agrawal@arm.com> > --- Thanks, applied (adding a Fixes: tag, please use those in the future) -Olof
Hi, On Wed, Jul 30, 2014 at 12:54 PM, Olof Johansson <olof@lixom.net> wrote: > On Wed, Jul 30, 2014 at 11:37:35AM +0100, Punit Agrawal wrote: >> From: Himangi Saraogi <himangi774@gmail.com> >> >> In commit ae91d60ba88ef0bdb1b5e9b2363bd52fc45d2af7, a bug was fixed that >> involved converting !x & y to !(x & y). The code below shows the same >> pattern, and thus should perhaps be fixed in the same way. >> >> The Coccinelle semantic patch that makes this change is as follows: >> >> // <smpl> >> @@ expression E1,E2; @@ >> ( >> !E1 & !E2 >> | >> - !E1 & E2 >> + !(E1 & E2) >> ) >> // </smpl> >> >> Cc: stable@vger.kernel.org >> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> >> Acked-by: Julia Lawall <julia.lawall@lip6.fr> >> Acked-by: Punit Agrawal <punit.agrawal@arm.com> >> --- > > Thanks, applied (adding a Fixes: tag, please use those in the future) On second look, I see that the code doesn't actually change behavior (since the mask is done with 0x1, it happens to have the same result). Pure luck before. :) Because of this, I've moved this to our next/fixes-non-critical branch, which will be sent up during the 3.17 merge window, and I took off the stable cc. It's still a good fix, but since it doesn't actually fix broken behavior there's no need to rush it. -Olof
Hi Olof, Olof Johansson <olof@lixom.net> writes: > Hi, > > On Wed, Jul 30, 2014 at 12:54 PM, Olof Johansson <olof@lixom.net> wrote: >> On Wed, Jul 30, 2014 at 11:37:35AM +0100, Punit Agrawal wrote: >>> From: Himangi Saraogi <himangi774@gmail.com> >>> >>> In commit ae91d60ba88ef0bdb1b5e9b2363bd52fc45d2af7, a bug was fixed that >>> involved converting !x & y to !(x & y). The code below shows the same >>> pattern, and thus should perhaps be fixed in the same way. >>> >>> The Coccinelle semantic patch that makes this change is as follows: >>> >>> // <smpl> >>> @@ expression E1,E2; @@ >>> ( >>> !E1 & !E2 >>> | >>> - !E1 & E2 >>> + !(E1 & E2) >>> ) >>> // </smpl> >>> >>> Cc: stable@vger.kernel.org >>> Signed-off-by: Himangi Saraogi <himangi774@gmail.com> >>> Acked-by: Julia Lawall <julia.lawall@lip6.fr> >>> Acked-by: Punit Agrawal <punit.agrawal@arm.com> >>> --- >> >> Thanks, applied (adding a Fixes: tag, please use those in the future) Will do. > > On second look, I see that the code doesn't actually change behavior > (since the mask is done with 0x1, it happens to have the same result). > Pure luck before. :) Although I'd tested the original submission and had seen interrupts handled correctly, this fix made me question if I was mis-remembering (since this was about a year ago). I had convinced myself that the fix was required. Re-evaluating all the conditions after reading your response, I agree that it is not a change in behaviour but still a correct fix. > > Because of this, I've moved this to our next/fixes-non-critical > branch, which will be sent up during the 3.17 merge window, and I took > off the stable cc. It's still a good fix, but since it doesn't > actually fix broken behavior there's no need to rush it. Ack. Thanks a lot. > > > -Olof > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/drivers/bus/arm-cci.c b/drivers/bus/arm-cci.c index 5a86da9..7af78df 100644 --- a/drivers/bus/arm-cci.c +++ b/drivers/bus/arm-cci.c @@ -397,7 +397,8 @@ static irqreturn_t pmu_handle_irq(int irq_num, void *dev) hw_counter = &event->hw; /* Did this counter overflow? */ - if (!pmu_read_register(idx, CCI_PMU_OVRFLW) & CCI_PMU_OVRFLW_FLAG) + if (!(pmu_read_register(idx, CCI_PMU_OVRFLW) & + CCI_PMU_OVRFLW_FLAG)) continue; pmu_write_register(CCI_PMU_OVRFLW_FLAG, idx, CCI_PMU_OVRFLW);