[PATCH v3 2/2] mm, hwpoison: When copy-on-write hits poison, take page offline
From: Tony Luck <tony.luck@intel.com>
Date: 2022-10-21 20:01:38
Also in:
linux-mm, lkml
Subsystem:
memory management, memory management - core, the rest · Maintainers:
Andrew Morton, David Hildenbrand, Linus Torvalds
Cannot call memory_failure() directly from the fault handler because mmap_lock (and others) are held. It is important, but not urgent, to mark the source page as h/w poisoned and unmap it from other tasks. Use memory_failure_queue() to request a call to memory_failure() for the page with the error. Also provide a stub version for CONFIG_MEMORY_FAILURE=n Signed-off-by: Tony Luck <tony.luck@intel.com> --- include/linux/mm.h | 5 ++++- mm/memory.c | 4 +++- 2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 8bbcccbc5565..03ced659eb58 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h@@ -3268,7 +3268,6 @@ enum mf_flags { int mf_dax_kill_procs(struct address_space *mapping, pgoff_t index, unsigned long count, int mf_flags); extern int memory_failure(unsigned long pfn, int flags); -extern void memory_failure_queue(unsigned long pfn, int flags); extern void memory_failure_queue_kick(int cpu); extern int unpoison_memory(unsigned long pfn); extern int sysctl_memory_failure_early_kill;
@@ -3277,8 +3276,12 @@ extern void shake_page(struct page *p); extern atomic_long_t num_poisoned_pages __read_mostly; extern int soft_offline_page(unsigned long pfn, int flags); #ifdef CONFIG_MEMORY_FAILURE +extern void memory_failure_queue(unsigned long pfn, int flags); extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags); #else +static inline void memory_failure_queue(unsigned long pfn, int flags) +{ +} static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags) { return 0;
diff --git a/mm/memory.c b/mm/memory.c
index b6056eef2f72..eae242351726 100644
--- a/mm/memory.c
+++ b/mm/memory.c@@ -2866,8 +2866,10 @@ static inline int __wp_page_copy_user(struct page *dst, struct page *src, unsigned long addr = vmf->address; if (likely(src)) { - if (copy_mc_user_highpage(dst, src, addr, vma)) + if (copy_mc_user_highpage(dst, src, addr, vma)) { + memory_failure_queue(page_to_pfn(src), 0); return -EHWPOISON; + } return 0; }
--
2.37.3