[PATCH v10 4/6] mm/hwpoison: return -EFAULT when copy fail in copy_mc_[user]_highpage()
From: Tong Tiangen <hidden>
Date: 2024-01-29 13:47:11
Also in:
linux-arm-kernel, linux-mm, lkml
Subsystem:
memory management, memory management - core, memory management - thp (transparent huge page), the rest · Maintainers:
Andrew Morton, David Hildenbrand, Lorenzo Stoakes, Linus Torvalds
If hardware errors are encountered during page copying, returning the bytes not copied is not meaningful, and the caller cannot do any processing on the remaining data. Returning -EFAULT is more reasonable, which represents a hardware error encountered during the copying. Signed-off-by: Tong Tiangen <redacted> --- include/linux/highmem.h | 8 ++++---- mm/khugepaged.c | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 451c1dff0e87..c5ca1a1fc4f5 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h@@ -335,8 +335,8 @@ static inline void copy_highpage(struct page *to, struct page *from) /* * If architecture supports machine check exception handling, define the * #MC versions of copy_user_highpage and copy_highpage. They copy a memory - * page with #MC in source page (@from) handled, and return the number - * of bytes not copied if there was a #MC, otherwise 0 for success. + * page with #MC in source page (@from) handled, and return -EFAULT if there + * was a #MC, otherwise 0 for success. */ static inline int copy_mc_user_highpage(struct page *to, struct page *from, unsigned long vaddr, struct vm_area_struct *vma)
@@ -352,7 +352,7 @@ static inline int copy_mc_user_highpage(struct page *to, struct page *from, kunmap_local(vto); kunmap_local(vfrom); - return ret; + return ret ? -EFAULT : 0; } static inline int copy_mc_highpage(struct page *to, struct page *from)
@@ -368,7 +368,7 @@ static inline int copy_mc_highpage(struct page *to, struct page *from) kunmap_local(vto); kunmap_local(vfrom); - return ret; + return ret ? -EFAULT : 0; } #else static inline int copy_mc_user_highpage(struct page *to, struct page *from,
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 2b219acb528e..ba6743a54c86 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c@@ -797,7 +797,7 @@ static int __collapse_huge_page_copy(pte_t *pte, continue; } src_page = pte_page(pteval); - if (copy_mc_user_highpage(page, src_page, _address, vma) > 0) { + if (copy_mc_user_highpage(page, src_page, _address, vma)) { result = SCAN_COPY_MC; break; }
@@ -2053,7 +2053,7 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, clear_highpage(hpage + (index % HPAGE_PMD_NR)); index++; } - if (copy_mc_highpage(hpage + (page->index % HPAGE_PMD_NR), page) > 0) { + if (copy_mc_highpage(hpage + (page->index % HPAGE_PMD_NR), page)) { result = SCAN_COPY_MC; goto rollback; }
--
2.25.1