6 a.m.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
netfs-folio-regions
head: 215a4ee495a95cc73256ed76f91cb78bcabd6b8e
commit: 27ed0ce3a75fcb90e4c016da19682b7fb275ccaf [14/28] netfs: Initiate write request
from a dirty region
config: hexagon-randconfig-r041-20210818 (attached as .config)
compiler: clang version 12.0.0
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
#
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/com...
git remote add dhowells-fs
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
git fetch --no-tags dhowells-fs netfs-folio-regions
git checkout 27ed0ce3a75fcb90e4c016da19682b7fb275ccaf
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=hexagon
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All warnings (new ones prefixed by >>):
> fs/netfs/write_back.c:103:7: warning: variable 'ret' is
used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
if (!folio_trylock(folio))
^~~~~~~~~~~~~~~~~~~~~
fs/netfs/write_back.c:107:9: note: uninitialized use occurs here
return ret;
^~~
fs/netfs/write_back.c:103:3: note: remove the 'if' if its condition is always
true
if (!folio_trylock(folio))
^~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/write_back.c:90:9: note: initialize the variable 'ret' to silence this
warning
int ret;
^
= 0
1 warning generated.
vim +103 fs/netfs/write_back.c
84
85 static int netfs_lock_folios_iterator(struct xa_state *xas,
86 struct folio *folio,
87 struct netfs_write_request *wreq,
88 struct writeback_control *wbc)
89 {
90 int ret;
91
92 /* At this point we hold neither the i_pages lock nor the
93 * folio lock: the folio may be truncated or invalidated
94 * (changing folio->mapping to NULL), or even swizzled
95 * back from swapper_space to tmpfs file mapping
96 */
97 if (wbc->sync_mode != WB_SYNC_NONE) {
98 xas_pause(xas);
99 rcu_read_unlock();
100 ret = folio_lock_killable(folio);
101 rcu_read_lock();
102 } else {
103 if (!folio_trylock(folio))
104 ret = -EBUSY;
105 }
106
107 return ret;
108 }
109
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org