Re: [dm-devel] [dm:for-next 20/20] drivers/md/dm.c:850:43: warning: variable 'bio' is uninitialized when used here
On 2021/06/03 6:26, kernel test robot wrote:
> tree:
> https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git
> for-next
> head: 2c243153d1d4be4e23735cd10984ac17c7a54531
> commit: 2c243153d1d4be4e23735cd10984ac17c7a54531 [20/20] dm: Forbid requeue
> of writes to zones
> config: riscv-randconfig-r011-20210602 (attached as .config)
> compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project
> d41cb6bb2607fa5c7a9df2b3dab361353657d225)
> reproduce (this is a W=1 build):
> wget
> https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
> ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install riscv cross compiling tool for clang build
> # apt-get install binutils-riscv64-linux-gnu
> #
> https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/commit/?id=2c243153d1d4be4e23735cd10984ac17c7a54531
> git remote add dm
> https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git
> git fetch --no-tags dm for-next
> git checkout 2c243153d1d4be4e23735cd10984ac17c7a54531
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot
>
> All warnings (new ones prefixed by >>):
>
>>> drivers/md/dm.c:850:43: warning: variable 'bio' is uninitialized when used
>>> here [-Wuninitialized]
>!WARN_ON_ONCE(dm_is_zone_write(md, bio)))
> ^~~
>include/asm-generic/bug.h:102:25: note: expanded from macro 'WARN_ON_ONCE'
>int __ret_warn_on = !!(condition); \
> ^
>drivers/md/dm.c:832:17: note: initialize the variable 'bio' to silence
> this warning
>struct bio *bio;
> ^
>= NULL
>1 warning generated.
>
>
> vim +/bio +850 drivers/md/dm.c
>
>823
>824/*
>825 * Decrements the number of outstanding ios that a bio has been
>826 * cloned into, completing the original io if necc.
>827 */
>828static void dec_pending(struct dm_io *io, blk_status_t error)
>829{
>830unsigned long flags;
>831blk_status_t io_error;
>832struct bio *bio;
>833struct mapped_device *md = io->md;
>834
>835/* Push-back supersedes any I/O errors */
>836if (unlikely(error)) {
>837spin_lock_irqsave(>endio_lock, flags);
>838if (!(io->status == BLK_STS_DM_REQUEUE &&
> __noflush_suspending(md)))
>839io->status = error;
>840spin_unlock_irqrestore(>endio_lock, flags);
>841}
>842
>843if (atomic_dec_and_test(>io_count)) {
>844if (io->status == BLK_STS_DM_REQUEUE) {
>845/*
>846 * Target requested pushing back the
> I/O.
>847 */
>848spin_lock_irqsave(>deferred_lock,
> flags);
>849if (__noflush_suspending(md) &&
> > 850!WARN_ON_ONCE(dm_is_zone_write(md,
> bio)))
Mike,
This needs to be WARN_ON_ONCE(dm_is_zone_write(md, io->orig_bio)).
Or better, we can move line 863 below right after the
"if (atomic_dec_and_test(>io_count)) {" above.
Do you want me to resend ? Or can you fix it up ?
Thanks !
>851/* NOTE early return due to
> BLK_STS_DM_REQUEUE below */
>852
> bio_list_add_head(>deferred, io->orig_bio);
>853else
>854/*
>855 * noflush suspend was
> interrupted or this is
>856 * a write to a zoned target.
>857 */
>858io->status = BLK_STS_IOERR;
>859
> spin_unlock_irqrestore(>deferred_lock, flags);
>860}
>861
>862io_error = io->status;
>863bio = io->orig_bio;
>864end_io_acct(io);
>865free_io(md, io);
>866
>867if (io_error == BLK_STS_DM_REQUEUE)
>868return;
>869
>
[dm-devel] [dm:for-next 20/20] drivers/md/dm.c:850:43: warning: variable 'bio' is uninitialized when used here
tree:
https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git
for-next
head: 2c243153d1d4be4e23735cd10984ac17c7a54531
commit: 2c243153d1d4be4e23735cd10984ac17c7a54531 [20/20] dm: Forbid requeue of
writes to zones
config: riscv-randconfig-r011-20210602 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project
d41cb6bb2607fa5c7a9df2b3dab361353657d225)
reproduce (this is a W=1 build):
wget
https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
# install riscv cross compiling tool for clang build
# apt-get install binutils-riscv64-linux-gnu
#
https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git/commit/?id=2c243153d1d4be4e23735cd10984ac17c7a54531
git remote add dm
https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git
git fetch --no-tags dm for-next
git checkout 2c243153d1d4be4e23735cd10984ac17c7a54531
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot
All warnings (new ones prefixed by >>):
>> drivers/md/dm.c:850:43: warning: variable 'bio' is uninitialized when used
>> here [-Wuninitialized]
!WARN_ON_ONCE(dm_is_zone_write(md, bio)))
^~~
include/asm-generic/bug.h:102:25: note: expanded from macro 'WARN_ON_ONCE'
int __ret_warn_on = !!(condition); \
^
drivers/md/dm.c:832:17: note: initialize the variable 'bio' to silence this
warning
struct bio *bio;
^
= NULL
1 warning generated.
vim +/bio +850 drivers/md/dm.c
823
824 /*
825 * Decrements the number of outstanding ios that a bio has been
826 * cloned into, completing the original io if necc.
827 */
828 static void dec_pending(struct dm_io *io, blk_status_t error)
829 {
830 unsigned long flags;
831 blk_status_t io_error;
832 struct bio *bio;
833 struct mapped_device *md = io->md;
834
835 /* Push-back supersedes any I/O errors */
836 if (unlikely(error)) {
837 spin_lock_irqsave(>endio_lock, flags);
838 if (!(io->status == BLK_STS_DM_REQUEUE &&
__noflush_suspending(md)))
839 io->status = error;
840 spin_unlock_irqrestore(>endio_lock, flags);
841 }
842
843 if (atomic_dec_and_test(>io_count)) {
844 if (io->status == BLK_STS_DM_REQUEUE) {
845 /*
846 * Target requested pushing back the I/O.
847 */
848 spin_lock_irqsave(>deferred_lock, flags);
849 if (__noflush_suspending(md) &&
> 850 !WARN_ON_ONCE(dm_is_zone_write(md, bio)))
851 /* NOTE early return due to
BLK_STS_DM_REQUEUE below */
852 bio_list_add_head(>deferred,
io->orig_bio);
853 else
854 /*
855 * noflush suspend was interrupted or
this is
856 * a write to a zoned target.
857 */
858 io->status = BLK_STS_IOERR;
859 spin_unlock_irqrestore(>deferred_lock,
flags);
860 }
861
862 io_error = io->status;
863 bio = io->orig_bio;
864 end_io_acct(io);
865 free_io(md, io);
866
867 if (io_error == BLK_STS_DM_REQUEUE)
868 return;
869
870 if ((bio->bi_opf & REQ_PREFLUSH) &&
bio->bi_iter.bi_size) {
871 /*
872 * Preflush done for flush with data, reissue
873 * without REQ_PREFLUSH.
874 */
875 bio->bi_opf &= ~REQ_PREFLUSH;
876 queue_io(md, bio);
877 } else {
878 /* done with normal IO or empty flush */
879 if (io_error)
880 bio->bi_status = io_error;
881 bio_endio(bio);
882 }
883 }
884 }
885
---
0-DAY CI Kernel Test Service, Intel
