diff mbox series

[26/30] mm/memory-failure: Stop setting the folio error flag

Message ID 20240420025029.2166544-27-willy@infradead.org (mailing list archive)
State New, archived
Headers show
Series Remove PG_error flag | expand

Commit Message

Matthew Wilcox April 20, 2024, 2:50 a.m. UTC
Nobody checks the error flag any more, so setting it accomplishes
nothing.  Remove the obsolete parts of this comment; it hasn't
been true since errseq_t was used to track writeback errors in 2017.

Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: linux-mm@kvack.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 mm/memory-failure.c | 29 -----------------------------
 1 file changed, 29 deletions(-)
diff mbox series

Patch

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index ec30611ec5ad..e065dd9be21e 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1092,7 +1092,6 @@  static int me_pagecache_dirty(struct page_state *ps, struct page *p)
 {
 	struct address_space *mapping = page_mapping(p);
 
-	SetPageError(p);
 	/* TBD: print more information about the file. */
 	if (mapping) {
 		/*
@@ -1100,34 +1099,6 @@  static int me_pagecache_dirty(struct page_state *ps, struct page *p)
 		 * who check the mapping.
 		 * This way the application knows that something went
 		 * wrong with its dirty file data.
-		 *
-		 * There's one open issue:
-		 *
-		 * The EIO will be only reported on the next IO
-		 * operation and then cleared through the IO map.
-		 * Normally Linux has two mechanisms to pass IO error
-		 * first through the AS_EIO flag in the address space
-		 * and then through the PageError flag in the page.
-		 * Since we drop pages on memory failure handling the
-		 * only mechanism open to use is through AS_AIO.
-		 *
-		 * This has the disadvantage that it gets cleared on
-		 * the first operation that returns an error, while
-		 * the PageError bit is more sticky and only cleared
-		 * when the page is reread or dropped.  If an
-		 * application assumes it will always get error on
-		 * fsync, but does other operations on the fd before
-		 * and the page is dropped between then the error
-		 * will not be properly reported.
-		 *
-		 * This can already happen even without hwpoisoned
-		 * pages: first on metadata IO errors (which only
-		 * report through AS_EIO) or when the page is dropped
-		 * at the wrong time.
-		 *
-		 * So right now we assume that the application DTRT on
-		 * the first EIO, but we're not worse than other parts
-		 * of the kernel.
 		 */
 		mapping_set_error(mapping, -EIO);
 	}