From ebbe7d7bb1eae4db32554562f0e228824ab1f135 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 26 Aug 2025 15:09:48 +0200 Subject: mm: fix lockdep issues in writeback handling Commit 2841808f35ee ("mm: remove BDI_CAP_WRITEBACK_ACCT") removed BDI_CAP_WRITEBACK_ACCT flag and refactored code that depend on it. Unfortunately it also moved some variable intialization out of guarded scope in writeback handling, what triggers a true lockdep warning. Fix this by moving initialization to the proper place. Fixes: 2841808f35ee ("mm: remove BDI_CAP_WRITEBACK_ACCT") Signed-off-by: Marek Szyprowski Acked-by: David Hildenbrand Reviewed-by: Joanne Koong Signed-off-by: Miklos Szeredi --- mm/page-writeback.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'mm/page-writeback.c') diff --git a/mm/page-writeback.c b/mm/page-writeback.c index de669636120d..e359f141639d 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -3014,7 +3014,7 @@ bool __folio_end_writeback(struct folio *folio) if (mapping && mapping_use_writeback_tags(mapping)) { struct inode *inode = mapping->host; - struct bdi_writeback *wb = inode_to_wb(inode); + struct bdi_writeback *wb; unsigned long flags; xa_lock_irqsave(&mapping->i_pages, flags); @@ -3022,6 +3022,7 @@ bool __folio_end_writeback(struct folio *folio) __xa_clear_mark(&mapping->i_pages, folio_index(folio), PAGECACHE_TAG_WRITEBACK); + wb = inode_to_wb(inode); wb_stat_mod(wb, WB_WRITEBACK, -nr); __wb_writeout_add(wb, nr); if (!mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) { @@ -3054,7 +3055,7 @@ void __folio_start_writeback(struct folio *folio, bool keep_write) if (mapping && mapping_use_writeback_tags(mapping)) { XA_STATE(xas, &mapping->i_pages, folio_index(folio)); struct inode *inode = mapping->host; - struct bdi_writeback *wb = inode_to_wb(inode); + struct bdi_writeback *wb; unsigned long flags; bool on_wblist; @@ -3065,6 +3066,7 @@ void __folio_start_writeback(struct folio *folio, bool keep_write) on_wblist = mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK); xas_set_mark(&xas, PAGECACHE_TAG_WRITEBACK); + wb = inode_to_wb(inode); wb_stat_mod(wb, WB_WRITEBACK, nr); if (!on_wblist) { wb_inode_writeback_start(wb); -- cgit v1.2.3