Re: Machine check recovery broken in v6.9-rc1

From: Oscar Salvador
Date: Fri Apr 05 2024 - 23:54:59 EST


On Sat, Apr 06, 2024 at 04:18:41AM +0200, Oscar Salvador wrote:
> Tony, could you try the following patch, to see if that goes away?
> It is against 6.1, but current kernel has the same problem AFAICS.
>
>
> diff --git a/include/linux/swapops.h b/include/linux/swapops.h
> index 578212fbf2be..575d428393c0 100644
> --- a/include/linux/swapops.h
> +++ b/include/linux/swapops.h
> @@ -416,7 +416,7 @@ static inline bool is_pfn_swap_entry(swp_entry_t entry)
> BUILD_BUG_ON(SWP_TYPE_SHIFT < SWP_PFN_BITS);
>
> return is_migration_entry(entry) || is_device_private_entry(entry) ||
> - is_device_exclusive_entry(entry);
> + is_device_exclusive_entry(entry) || is_hwpsoion_entry(entry);
> }
>
> struct page_vma_mapped_walk;

Sorry, I was still sleepy and I made a typo.
Plus I realized we need to move some definitions to make them available.

This should have been (compile tested only):

diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index 48b700ba1d18..201efbf441d6 100644
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -390,6 +390,35 @@ static inline bool is_migration_entry_dirty(swp_entry_t entry)
}
#endif /* CONFIG_MIGRATION */

+#ifdef CONFIG_MEMORY_FAILURE
+
+/*
+ * Support for hardware poisoned pages
+ */
+static inline swp_entry_t make_hwpoison_entry(struct page *page)
+{
+ BUG_ON(!PageLocked(page));
+ return swp_entry(SWP_HWPOISON, page_to_pfn(page));
+}
+
+static inline int is_hwpoison_entry(swp_entry_t entry)
+{
+ return swp_type(entry) == SWP_HWPOISON;
+}
+
+#else
+
+static inline swp_entry_t make_hwpoison_entry(struct page *page)
+{
+ return swp_entry(0, 0);
+}
+
+static inline int is_hwpoison_entry(swp_entry_t swp)
+{
+ return 0;
+}
+#endif
+
typedef unsigned long pte_marker;

#define PTE_MARKER_UFFD_WP BIT(0)
@@ -492,7 +521,7 @@ static inline bool is_pfn_swap_entry(swp_entry_t entry)
BUILD_BUG_ON(SWP_TYPE_SHIFT < SWP_PFN_BITS);

return is_migration_entry(entry) || is_device_private_entry(entry) ||
- is_device_exclusive_entry(entry);
+ is_device_exclusive_entry(entry) || is_hwpoison_entry(entry);
}

struct page_vma_mapped_walk;
@@ -561,35 +590,6 @@ static inline int is_pmd_migration_entry(pmd_t pmd)
}
#endif /* CONFIG_ARCH_ENABLE_THP_MIGRATION */

-#ifdef CONFIG_MEMORY_FAILURE
-
-/*
- * Support for hardware poisoned pages
- */
-static inline swp_entry_t make_hwpoison_entry(struct page *page)
-{
- BUG_ON(!PageLocked(page));
- return swp_entry(SWP_HWPOISON, page_to_pfn(page));
-}
-
-static inline int is_hwpoison_entry(swp_entry_t entry)
-{
- return swp_type(entry) == SWP_HWPOISON;
-}
-
-#else
-
-static inline swp_entry_t make_hwpoison_entry(struct page *page)
-{
- return swp_entry(0, 0);
-}
-
-static inline int is_hwpoison_entry(swp_entry_t swp)
-{
- return 0;
-}
-#endif
-
static inline int non_swap_entry(swp_entry_t entry)
{
return swp_type(entry) >= MAX_SWAPFILES;


--
Oscar Salvador
SUSE Labs