Re: [PATCH] usbip: usbip_host: fix stub_dev lock context imbalance regression

[Shuah Khan]

On 5/29/19 2:25 PM, Greg KH wrote:
> On Wed, May 29, 2019 at 01:46:15PM -0600, Shuah Khan wrote:
> > Fix the following sparse context imbalance regression introduced in
> > a patch that fixed sleeping function called from invalid context bug.
> >
> > kbuild test robot reported on:
> >
> > tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git  usb-linus
> >
> > Regressions in current branch:
> >
> > drivers/usb/usbip/stub_dev.c:399:9: sparse: sparse: context imbalance in 'stub_probe' - different lock contexts for basic block
> > drivers/usb/usbip/stub_dev.c:418:13: sparse: sparse: context imbalance in 'stub_disconnect' - different lock contexts for basic block
> > drivers/usb/usbip/stub_dev.c:464:1-10: second lock on line 476
> >
> > Error ids grouped by kconfigs:
> >
> > recent_errors
> > âââ i386-allmodconfig
> > â   âââ drivers-usb-usbip-stub_dev.c:second-lock-on-line
> > âââ x86_64-allmodconfig
> > â   âââ drivers-usb-usbip-stub_dev.c:sparse:sparse:context-imbalance-in-stub_disconnect-different-lock-contexts-for-basic-block
> > â   âââ drivers-usb-usbip-stub_dev.c:sparse:sparse:context-imbalance-in-stub_probe-different-lock-contexts-for-basic-block
> > âââ x86_64-allyesconfig
> >      âââ drivers-usb-usbip-stub_dev.c:second-lock-on-line
> >
> > This is a real problem in an error leg where spin_lock() is called on an
> > already held lock.
> >
> > Fix the imbalance in stub_probe() and stub_disconnect().
> >
> > Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
>
> I'll go add:
>
> Fixes: 0c9e8b3cad65 ("usbip: usbip_host: fix BUG: sleeping function called from invalid context")
> Cc: stable <stable@xxxxxxxxxxxxxxx>
>
> as the patch this fixes was tagged for stable.

Sounds good. Thanks.

-- Shuah