[ammarfaizi2-block:dhowells/linux-fs/netfs-maple 31/42] fs/netfs/buffered_write.c:749:6: warning: variable 'spare_region' is used uninitialized whenever 'if' condition is true
From: kernel test robot
Date: Wed Feb 16 2022 - 18:47:59 EST
tree: https://github.com/ammarfaizi2/linux-block dhowells/linux-fs/netfs-maple
head: 5cb7f190822d09757b30cd9539e57eef72552d1f
commit: eefdd180445e96088f4a69f0e733643e9a794b1f [31/42] netfs: Allow buffered shared-writeable mmap through netfs_page_mkwrite()
config: hexagon-randconfig-r005-20220216 (https://download.01.org/0day-ci/archive/20220217/202202170739.jOmFwlAm-lkp@xxxxxxxxx/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0e628a783b935c70c80815db6c061ec84f884af5)
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://github.com/ammarfaizi2/linux-block/commit/eefdd180445e96088f4a69f0e733643e9a794b1f
git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
git fetch --no-tags ammarfaizi2-block dhowells/linux-fs/netfs-maple
git checkout eefdd180445e96088f4a69f0e733643e9a794b1f
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash fs/netfs/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
All warnings (new ones prefixed by >>):
fs/netfs/buffered_write.c:28:26: warning: comparison of distinct pointer types ('typeof ((1UL << 14) - offset) *' (aka 'unsigned long *') and 'typeof (size) *' (aka 'unsigned int *')) [-Wcompare-distinct-pointer-types]
unsigned int psize = min(PAGE_SIZE - offset, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:45:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(x, y, <)
^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~~~~~~~
include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~~~~~~~
include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:95:18: warning: comparison of distinct pointer types ('typeof (target->from) *' (aka 'unsigned long long *') and 'typeof (folio_pos(folio) + offset) *' (aka 'long long *')) [-Wcompare-distinct-pointer-types]
target->from = min(target->from, folio_pos(folio) + offset);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:45:19: note: expanded from macro 'min'
#define min(x, y) __careful_cmp(x, y, <)
^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~~~~~~~
include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~~~~~~~
include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:96:18: warning: comparison of distinct pointer types ('typeof (target->to) *' (aka 'unsigned long long *') and 'typeof (folio_pos(folio) + offset + len) *' (aka 'long long *')) [-Wcompare-distinct-pointer-types]
target->to = max(target->to, folio_pos(folio) + offset + len);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:52:19: note: expanded from macro 'max'
#define max(x, y) __careful_cmp(x, y, >)
^~~~~~~~~~~~~~~~~~~~~~
include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
__builtin_choose_expr(__safe_cmp(x, y), \
^~~~~~~~~~~~~~~~
include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
(__typecheck(x, y) && __no_side_effects(x, y))
^~~~~~~~~~~~~~~~~
include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
(!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~
>> fs/netfs/buffered_write.c:749:6: warning: variable 'spare_region' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (mas_expected_entries(&mas, 2) < 0) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:785:30: note: uninitialized use occurs here
netfs_put_dirty_region(ctx, spare_region, netfs_region_trace_put_discard);
^~~~~~~~~~~~
fs/netfs/buffered_write.c:749:2: note: remove the 'if' if its condition is always false
if (mas_expected_entries(&mas, 2) < 0) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:746:6: warning: variable 'spare_region' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (folio_lock_killable(folio) < 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:785:30: note: uninitialized use occurs here
netfs_put_dirty_region(ctx, spare_region, netfs_region_trace_put_discard);
^~~~~~~~~~~~
fs/netfs/buffered_write.c:746:2: note: remove the 'if' if its condition is always false
if (folio_lock_killable(folio) < 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:743:6: warning: variable 'spare_region' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (folio_wait_writeback_killable(folio))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:785:30: note: uninitialized use occurs here
netfs_put_dirty_region(ctx, spare_region, netfs_region_trace_put_discard);
^~~~~~~~~~~~
fs/netfs/buffered_write.c:743:2: note: remove the 'if' if its condition is always false
if (folio_wait_writeback_killable(folio))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/netfs/buffered_write.c:726:41: note: initialize the variable 'spare_region' to silence this warning
struct netfs_dirty_region *spare_region;
^
= NULL
6 warnings generated.
vim +749 fs/netfs/buffered_write.c
719
720 /*
721 * Notification that a previously read-only page is about to become writable.
722 * Note that the caller indicates a single page of a multipage folio.
723 */
724 vm_fault_t netfs_page_mkwrite(struct vm_fault *vmf)
725 {
726 struct netfs_dirty_region *spare_region;
727 struct folio *folio = page_folio(vmf->page);
728 struct file *file = vmf->vma->vm_file;
729 struct inode *inode = file_inode(file);
730 struct netfs_i_context *ctx = netfs_i_context(inode);
731 vm_fault_t ret = VM_FAULT_RETRY;
732 int err;
733
734 MA_STATE(mas, &ctx->dirty_regions, vmf->page->index, PAGE_SIZE);
735
736 _enter("%lx", folio->index);
737
738 if (ctx->ops->validate_for_write(inode, file) < 0)
739 return VM_FAULT_SIGBUS;
740
741 sb_start_pagefault(inode->i_sb);
742
743 if (folio_wait_writeback_killable(folio))
744 goto out;
745
746 if (folio_lock_killable(folio) < 0)
747 goto out;
748
> 749 if (mas_expected_entries(&mas, 2) < 0) {
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx