>-----Original Message----- >From: Jeff Layton <jlayton@xxxxxxxxxx> >Sent: 2020年6月2日 21:52 >To: lkp <lkp@xxxxxxxxx> >Cc: kbuild-all@xxxxxxxxxxxx; ceph-devel@xxxxxxxxxxxxxxx; Ilya Dryomov ><idryomov@xxxxxxxxx> >Subject: Re: [ceph-client:testing 9/30] include/linux/spinlock.h:353:9: sparse: >sparse: context imbalance in 'ceph_handle_caps' - unexpected unlock > >On Tue, 2020-06-02 at 12:38 +0800, kbuild test robot wrote: >> tree: https://github.com/ceph/ceph-client.git testing >> head: 9c4e2af200ffe80d2f917b75f92ab57f0a091a17 >> commit: 7833323363233c75fd8d10b5ceefbb9515cb3e32 [9/30] ceph: don't >> take i_ceph_lock in handle_cap_import >> config: microblaze-randconfig-s031-20200602 (attached as .config) >> compiler: microblaze-linux-gcc (GCC) 9.3.0 >> reproduce: >> # apt-get install sparse >> # sparse version: v0.6.1-243-gc100a7ab-dirty >> git checkout 7833323363233c75fd8d10b5ceefbb9515cb3e32 >> # save the attached .config to linux build tree >> make W=1 C=1 ARCH=microblaze CF='-fdiagnostic-prefix - >D__CHECK_ENDIAN__' >> >> If you fix the issue, kindly add following tag as appropriate >> Reported-by: kbuild test robot <lkp@xxxxxxxxx> >> >> >> sparse warnings: (new ones prefixed by >>) >> >> fs/ceph/caps.c:3443:9: sparse: sparse: context imbalance in >> 'handle_cap_grant' - wrong count at exit >> > > include/linux/spinlock.h:353:9: sparse: sparse: context imbalance >> > > in 'ceph_handle_caps' - unexpected unlock >> >> vim +/ceph_handle_caps +353 include/linux/spinlock.h >> >> de8f5e4f2dc1f0 Peter Zijlstra 2020-03-21 350 >> 3490565b633c70 Denys Vlasenko 2015-07-13 351 static __always_inline >> void spin_lock(spinlock_t *lock) >> c2f21ce2e31286 Thomas Gleixner 2009-12-02 352 { >> c2f21ce2e31286 Thomas Gleixner 2009-12-02 @353 raw_spin_lock(&lock- >>rlock); >> c2f21ce2e31286 Thomas Gleixner 2009-12-02 354 } >> c2f21ce2e31286 Thomas Gleixner 2009-12-02 355 >> >> :::::: The code at line 353 was first introduced by commit >> :::::: c2f21ce2e31286a0a32f8da0a7856e9ca1122ef3 locking: Implement new >> raw_spinlock >> >> :::::: TO: Thomas Gleixner <tglx@xxxxxxxxxxxxx> >> :::::: CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx> >> >> --- >> 0-DAY CI Kernel Test Service, Intel Corporation >> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx > >I think this is a false-positive, but I'd welcome someone else to sanity check me >here (Ilya?). My sparse says something a little different: > > fs/ceph/caps.c:4052:26: warning: context imbalance in 'ceph_handle_caps' - >unexpected unlock > >...and I get a similar warning when I move to the commit ahead of >7833323363233c as well. Hi Jeff. Yes, the previous commit and older commit has similar warning. So it should not introduced by this commit. Please ignore it. The warning was treated as new one because the file name change(fs/ceph/caps.c:4052 --> include/linux/spinlock.h). Which might be sparse behavior. Sorry for the noise. > >All that patch does is push the i_ceph_lock acquisition from handle_cap_import >to ceph_handle_caps. I don't see how it would have introduced a locking >imbalance, but the locking in this code really is quite confusing, so please do point >it out if I'm wrong here. > >Thanks, >-- >Jeff Layton <jlayton@xxxxxxxxxx>
