| Message ID | 20181130125834.u42dhxgof66rhya2@kili.mountain |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
| Series | ptp: fix an IS_ERR() vs NULL check | expand |
On Fri, Nov 30, 2018 at 03:58:34PM +0300, Dan Carpenter wrote: > The pps_register_source() function doesn't return NULL, it returns > error pointers. It keeps a local variable for errno, but then it returns NULL. But this is about to change with this recent patch: 26.Nov'18 YueHaibing [PATCH -next] pps: using ERR_PTR instead of NULL while pps_register_source fails It hasn't been merged yet AFAICT, but gregkh said he take it. Thanks, Richard
On Fri, Nov 30, 2018 at 08:32:52AM -0800, Richard Cochran wrote: > On Fri, Nov 30, 2018 at 03:58:34PM +0300, Dan Carpenter wrote: > > The pps_register_source() function doesn't return NULL, it returns > > error pointers. > > It keeps a local variable for errno, but then it returns NULL. > But this is about to change with this recent patch: > > 26.Nov'18 YueHaibing [PATCH -next] pps: using ERR_PTR instead of NULL while pps_register_source fails > > It hasn't been merged yet AFAICT, but gregkh said he take it. Oh, yeah. That patch has actually been applied, but we didn't update the caller. I should have made the Fixes tag point to that YueHaibing's patch. regards, dan carpenter
On Mon, Dec 03, 2018 at 01:55:06PM +0300, Dan Carpenter wrote: > We recently modified pps_register_source() to return error pointers > instead of NULL but this check wasn't updated. But it *was* updated! > Fixes: 3b1ad360acad ("pps: using ERR_PTR instead of NULL while pps_register_source fails") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > --- > v2: Use the correct Fixes tag. Add Greg to the CC list, because he > is maintaining this driver. What driver? (I am maintaining drivers/ptp/ptp_clock.c) > drivers/ptp/ptp_clock.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c > index 8a81eecc0ecd..48f3594a7458 100644 > --- a/drivers/ptp/ptp_clock.c > +++ b/drivers/ptp/ptp_clock.c > @@ -265,8 +265,8 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, > pps.mode = PTP_PPS_MODE; > pps.owner = info->owner; > ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS); > - if (!ptp->pps_source) { > - err = -EINVAL; > + if (IS_ERR(ptp->pps_source)) { > + err = PTR_ERR(ptp->pps_source); > pr_err("failed to register pps source\n"); > goto no_pps; > } YueHaibing's patch has the following hunk. It really is already there. I don't see it yet on Linus' master branch, but the patch should update drivers/pps/kapi.c and the callers all in one commit. diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 8a81eec..48f3594 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -265,8 +265,8 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, pps.mode = PTP_PPS_MODE; pps.owner = info->owner; ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS); - if (!ptp->pps_source) { - err = -EINVAL; + if (IS_ERR(ptp->pps_source)) { + err = PTR_ERR(ptp->pps_source); pr_err("failed to register pps source\n"); goto no_pps; } Thanks, Richard
Hi Greg,
I meant to CC you but I screwed up and added you to the From header
instead... :(
Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL
while pps_register_source fails")? You're not listed as a maintainer so
I wouldn't have known to CC you.
The back story is that the last chunk which changes drivers/ptp/ptp_clock.c
was dropped by mistake and it's not there in linux-next. I wrote a
patch which adds it, but everyone is super confused now... Here is
YueHaibing's original patch btw, for reference.
https://www.spinics.net/lists/netdev/msg535929.html
regards,
dan carpenter
On Mon, Dec 03, 2018 at 08:42:57PM -0800, Richard Cochran wrote:
> On Mon, Dec 03, 2018 at 01:55:06PM +0300, Dan Carpenter wrote:
> > We recently modified pps_register_source() to return error pointers
> > instead of NULL but this check wasn't updated.
>
> But it *was* updated!
>
> > Fixes: 3b1ad360acad ("pps: using ERR_PTR instead of NULL while pps_register_source fails")
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> > ---
> > v2: Use the correct Fixes tag. Add Greg to the CC list, because he
> > is maintaining this driver.
>
> What driver? (I am maintaining drivers/ptp/ptp_clock.c)
>
> > drivers/ptp/ptp_clock.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
> > index 8a81eecc0ecd..48f3594a7458 100644
> > --- a/drivers/ptp/ptp_clock.c
> > +++ b/drivers/ptp/ptp_clock.c
> > @@ -265,8 +265,8 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
> > pps.mode = PTP_PPS_MODE;
> > pps.owner = info->owner;
> > ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
> > - if (!ptp->pps_source) {
> > - err = -EINVAL;
> > + if (IS_ERR(ptp->pps_source)) {
> > + err = PTR_ERR(ptp->pps_source);
> > pr_err("failed to register pps source\n");
> > goto no_pps;
> > }
>
> YueHaibing's patch has the following hunk. It really is already
> there. I don't see it yet on Linus' master branch, but the patch
> should update drivers/pps/kapi.c and the callers all in one commit.
>
> diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
> index 8a81eec..48f3594 100644
> --- a/drivers/ptp/ptp_clock.c
> +++ b/drivers/ptp/ptp_clock.c
> @@ -265,8 +265,8 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
> pps.mode = PTP_PPS_MODE;
> pps.owner = info->owner;
> ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS);
> - if (!ptp->pps_source) {
> - err = -EINVAL;
> + if (IS_ERR(ptp->pps_source)) {
> + err = PTR_ERR(ptp->pps_source);
> pr_err("failed to register pps source\n");
> goto no_pps;
> }
>
> Thanks,
> Richard
On Tue, Dec 04, 2018 at 10:00:33AM +0300, Dan Carpenter wrote: > Hi Greg, > > I meant to CC you but I screwed up and added you to the From header > instead... :( > > Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL > while pps_register_source fails")? You're not listed as a maintainer so > I wouldn't have known to CC you. The maintainer told me to do so, see this email thread: https://lore.kernel.org/lkml/44edc27b-e679-24e8-aef1-fe5b7570f982@enneenne.com/ > The back story is that the last chunk which changes drivers/ptp/ptp_clock.c > was dropped by mistake and it's not there in linux-next. I wrote a > patch which adds it, but everyone is super confused now... Here is > YueHaibing's original patch btw, for reference. > https://www.spinics.net/lists/netdev/msg535929.html If you want me to take a fixup patch for this, I will be glad to. I can also drop it from my tree as well, just let me know. Sorry for the confusion. greg k-h
On Tue, Dec 04, 2018 at 10:00:33AM +0300, Dan Carpenter wrote: > > Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL > while pps_register_source fails")? You're not listed as a maintainer so > I wouldn't have known to CC you. I'm confused. Where is that commit? $ git show 3b1ad360acad fatal: ambiguous argument '3b1ad360acad': unknown revision or path not in the working tree. I'm pulling from: torvalds git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git (fetch) stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git (fetch) (and also from net and net-next) Thanks, Richard
On Tue, Dec 04, 2018 at 06:55:38AM -0800, Richard Cochran wrote: > On Tue, Dec 04, 2018 at 10:00:33AM +0300, Dan Carpenter wrote: > > > > Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL > > while pps_register_source fails")? You're not listed as a maintainer so > > I wouldn't have known to CC you. > > I'm confused. Where is that commit? > > $ git show 3b1ad360acad > fatal: ambiguous argument '3b1ad360acad': unknown revision or path not in the working tree. > > I'm pulling from: > > torvalds git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git (fetch) > stable git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git (fetch) > > (and also from net and net-next) > I'm on linux-next but originally it came from the char-misc-next tree. git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git char-misc-next regards, dan carpenter
Greg, On Tue, Dec 04, 2018 at 06:10:49PM +0300, Dan Carpenter wrote: > On Tue, Dec 04, 2018 at 06:55:38AM -0800, Richard Cochran wrote: > > On Tue, Dec 04, 2018 at 10:00:33AM +0300, Dan Carpenter wrote: > > > > > > Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL > > > while pps_register_source fails")? You're not listed as a maintainer so > > > I wouldn't have known to CC you. > > > > I'm confused. Where is that commit? ... > I'm on linux-next but originally it came from the char-misc-next tree. > > git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git char-misc-next Commit 3b1ad360acad changes a return value in the PPS core, but it is missing the hunk for the caller in drivers/ptp/ptp_clock.c. Can that be amended? Thanks, Richard
On Thu, Dec 06, 2018 at 04:38:43AM -0800, Richard Cochran wrote: > Greg, > > On Tue, Dec 04, 2018 at 06:10:49PM +0300, Dan Carpenter wrote: > > On Tue, Dec 04, 2018 at 06:55:38AM -0800, Richard Cochran wrote: > > > On Tue, Dec 04, 2018 at 10:00:33AM +0300, Dan Carpenter wrote: > > > > > > > > Why did you commit 3b1ad360acad ("pps: using ERR_PTR instead of NULL > > > > while pps_register_source fails")? You're not listed as a maintainer so > > > > I wouldn't have known to CC you. > > > > > > I'm confused. Where is that commit? > > ... > > > I'm on linux-next but originally it came from the char-misc-next tree. > > > > git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git char-misc-next > > Commit 3b1ad360acad changes a return value in the PPS core, but it is > missing the hunk for the caller in drivers/ptp/ptp_clock.c. Can that > be amended? Send me a patch or tell me what I need to revert and I will be glad to do so :) thanks, greg k-h
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 8a81eecc0ecd..48f3594a7458 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -265,8 +265,8 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, pps.mode = PTP_PPS_MODE; pps.owner = info->owner; ptp->pps_source = pps_register_source(&pps, PTP_PPS_DEFAULTS); - if (!ptp->pps_source) { - err = -EINVAL; + if (IS_ERR(ptp->pps_source)) { + err = PTR_ERR(ptp->pps_source); pr_err("failed to register pps source\n"); goto no_pps; }
The pps_register_source() function doesn't return NULL, it returns error pointers. Fixes: d94ba80ebbea ("ptp: Added a brand new class driver for ptp clocks.") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- drivers/ptp/ptp_clock.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)