Hi Kanchana, kernel test robot noticed the following build warnings: url: https://github.com/intel-lab-lkp/linux/commits/Kanchana-P-Sridhar/crypto-acomp-Define-two-new-interfaces-for-compress-decompress-batching/20241103-112337 base: 5c4cf96cd70230100b5d396d45a5c9a332539d19 patch link: https://lore.kernel.org/r/20241103032111.333282-14-kanchana.p.sridhar%40intel.com patch subject: [PATCH v2 13/13] mm: zswap: Compress batching with Intel IAA in zswap_store() of large folios. config: x86_64-randconfig-161-20241104 (https://download.01.org/0day-ci/archive/20241104/202411040859.2z0MfFkR-lkp@xxxxxxxxx/config) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> | Closes: https://lore.kernel.org/r/202411040859.2z0MfFkR-lkp@xxxxxxxxx/ smatch warnings: mm/zswap.c:1788 zswap_store_propagate_errors() warn: variable dereferenced before check 'sbp->entry' (see line 1785) vim +1788 mm/zswap.c c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1771 static __always_inline void zswap_store_propagate_errors( c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1772 struct zswap_store_pipeline_state *zst, c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1773 u8 error_batch_idx) c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1774 { c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1775 u8 i; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1776 c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1777 if (zst->errors[error_batch_idx]) c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1778 return; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1779 c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1780 for (i = 0; i < zst->nr_comp_pages; ++i) { c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1781 struct zswap_store_sub_batch_page *sbp = &zst->sub_batch[i]; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1782 c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1783 if (sbp->batch_idx == error_batch_idx) { c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1784 if (!sbp->error) { c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 @1785 if (!IS_ERR_VALUE(sbp->entry->handle)) ^^^^^^^^^^^^^^^^^^ Dereferenced c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1786 zpool_free(zst->pool->zpool, sbp->entry->handle); c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1787 c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 @1788 if (sbp->entry) { ^^^^^^^^^^ Checked too late c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1789 zswap_entry_cache_free(sbp->entry); c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1790 sbp->entry = NULL; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1791 } c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1792 sbp->error = -EINVAL; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1793 } c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1794 } c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1795 } c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1796 c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1797 /* c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1798 * Set zswap status for the folio to "error" c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1799 * for use in swap_writepage. c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1800 */ c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1801 zst->errors[error_batch_idx] = -EINVAL; c1252ac91d6a6a Kanchana P Sridhar 2024-11-02 1802 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki