Hi Damien, I love your patch! Perhaps something to improve: [auto build test WARNING on block/for-next] [also build test WARNING on scsi/for-next mkp-scsi/for-next v5.14-rc2 next-20210723] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Damien-Le-Moal/Initial-support-f... base: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next :::::: branch date: 26 hours ago :::::: commit date: 26 hours ago config: x86_64-randconfig-c001-20210723 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 9625ca5b602616b2f5584e8a49ba93c52c141e40) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://github.com/0day-ci/linux/commit/5bede30cfe0b7db2174fbf8393a311fb2... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Damien-Le-Moal/Initial-support-for-multi-actuator-HDDs/20210723-092320 git checkout 5bede30cfe0b7db2174fbf8393a311fb21baa66a # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; clang-analyzer warnings: (new ones prefixed by >>) ^~~~~~~~~~~~ fs/fs-writeback.c:1198:6: note: Left side of '||' is false if (!skip_if_busy || !writeback_in_progress(&bdi->wb)) { ^ fs/fs-writeback.c:1198:23: note: Assuming the condition is true if (!skip_if_busy || !writeback_in_progress(&bdi->wb)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/fs-writeback.c:1198:2: note: Taking true branch if (!skip_if_busy || !writeback_in_progress(&bdi->wb)) { ^ fs/fs-writeback.c:1200:3: note: Calling 'wb_queue_work' wb_queue_work(&bdi->wb, base_work); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/fs-writeback.c:163:6: note: Assuming field 'done' is null if (work->done) ^~~~~~~~~~ fs/fs-writeback.c:163:2: note: Taking false branch if (work->done) ^ fs/fs-writeback.c:168:6: note: Assuming the condition is false if (test_bit(WB_registered, &wb->state)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/fs-writeback.c:168:2: note: Taking false branch if (test_bit(WB_registered, &wb->state)) { ^ fs/fs-writeback.c:172:3: note: Calling 'finish_writeback_work' finish_writeback_work(wb, work); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/fs-writeback.c:147:6: note: Assuming field 'auto_free' is not equal to 0 if (work->auto_free) ^~~~~~~~~~~~~~~ fs/fs-writeback.c:147:2: note: Taking true branch if (work->auto_free) ^ fs/fs-writeback.c:148:3: note: Argument to kfree() is the address of the local variable 'work', which is not memory allocated by malloc() kfree(work); ^ ~~~~ Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 4 warnings generated. Suppressed 4 warnings (4 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. if (!old || old->nr_ranges != new->nr_ranges) ^ block/blk-cranges.c:251:19: note: Assuming 'cr' is non-null if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { ^ include/asm-generic/bug.h:104:25: note: expanded from macro 'WARN_ON_ONCE' int __ret_warn_on = !!(condition); \ ^~~~~~~~~ block/blk-cranges.c:251:19: note: Left side of '&&' is true if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { ^ block/blk-cranges.c:251:25: note: Assuming field 'nr_ranges' is not equal to 0 if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { ^ include/asm-generic/bug.h:104:25: note: expanded from macro 'WARN_ON_ONCE' int __ret_warn_on = !!(condition); \ ^~~~~~~~~ block/blk-cranges.c:251:6: note: Taking false branch if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { ^ include/asm-generic/bug.h:105:2: note: expanded from macro 'WARN_ON_ONCE' if (unlikely(__ret_warn_on)) \ ^ block/blk-cranges.c:251:2: note: Taking false branch if (WARN_ON_ONCE(cr && !cr->nr_ranges)) { ^ block/blk-cranges.c:259:6: note: 'cr' is non-null if (cr && !blk_check_ranges(disk, cr)) { ^~ block/blk-cranges.c:259:6: note: Left side of '&&' is true block/blk-cranges.c:259:12: note: Assuming the condition is true if (cr && !blk_check_ranges(disk, cr)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~ block/blk-cranges.c:259:2: note: Taking true branch if (cr && !blk_check_ranges(disk, cr)) { ^ block/blk-cranges.c:261:3: note: Null pointer value stored to 'cr' cr = NULL; ^~~~~~~~~ block/blk-cranges.c:264:33: note: Passing null pointer value via 2nd parameter 'new' if (!blk_cranges_changed(disk, cr)) { ^~ block/blk-cranges.c:264:7: note: Calling 'blk_cranges_changed' if (!blk_cranges_changed(disk, cr)) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ block/blk-cranges.c:206:6: note: Assuming 'old' is non-null if (!old || old->nr_ranges != new->nr_ranges) ^~~~ block/blk-cranges.c:206:6: note: Left side of '||' is false block/blk-cranges.c:206:32: note: Access to field 'nr_ranges' results in a dereference of a null pointer (loaded from variable 'new') if (!old || old->nr_ranges != new->nr_ranges) ^~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 8 warnings generated. drivers/char/tpm/eventlog/tpm1.c:276:2: warning: Value stored to 'len' is never read [clang-analyzer-deadcode.DeadStores] len += get_event_name(eventname, event, event_entry); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/char/tpm/eventlog/tpm1.c:276:2: note: Value stored to 'len' is never read len += get_event_name(eventname, event, event_entry); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Suppressed 7 warnings (5 in non-user code, 2 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. Suppressed 5 warnings (4 in non-user code, 1 with check filters). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 5 warnings generated. vim +206 block/blk-cranges.c 5bede30cfe0b7d Damien Le Moal 2021-07-23 200 5bede30cfe0b7d Damien Le Moal 2021-07-23 201 static bool blk_cranges_changed(struct gendisk *disk, struct blk_cranges *new) 5bede30cfe0b7d Damien Le Moal 2021-07-23 202 { 5bede30cfe0b7d Damien Le Moal 2021-07-23 203 struct blk_cranges *old = disk->queue->cranges; 5bede30cfe0b7d Damien Le Moal 2021-07-23 204 int i; 5bede30cfe0b7d Damien Le Moal 2021-07-23 205 5bede30cfe0b7d Damien Le Moal 2021-07-23 @206 if (!old || old->nr_ranges != new->nr_ranges) 5bede30cfe0b7d Damien Le Moal 2021-07-23 207 return true; 5bede30cfe0b7d Damien Le Moal 2021-07-23 208 5bede30cfe0b7d Damien Le Moal 2021-07-23 209 for (i = 0; i < new->nr_ranges; i++) { 5bede30cfe0b7d Damien Le Moal 2021-07-23 210 if (old->ranges[i].sector != new->ranges[i].sector || 5bede30cfe0b7d Damien Le Moal 2021-07-23 211 old->ranges[i].nr_sectors != new->ranges[i].nr_sectors) 5bede30cfe0b7d Damien Le Moal 2021-07-23 212 return true; 5bede30cfe0b7d Damien Le Moal 2021-07-23 213 } 5bede30cfe0b7d Damien Le Moal 2021-07-23 214 5bede30cfe0b7d Damien Le Moal 2021-07-23 215 return false; 5bede30cfe0b7d Damien Le Moal 2021-07-23 216 } 5bede30cfe0b7d Damien Le Moal 2021-07-23 217 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org