HWPOISON: Add PROC_FS dependency to hwpoison injector v2

The injector filter requires stable_page_flags() which is supplied
by procfs. So make it dependent on that.

Also add ifdefs around the filter code in memory-failure.c so that
when the filter is disabled due to missing dependencies the whole
code still builds.

Reported-by: Ingo Molnar
Signed-off-by: Andi Kleen <ak@linux.intel.com>

2 files changed, 10 insertions, 1 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index ee9f3e0f2b69..17b8947aa7da 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -253,7 +253,7 @@ config MEMORY_FAILURE
 
 config HWPOISON_INJECT
         tristate "HWPoison pages injector"
-        depends on MEMORY_FAILURE && DEBUG_KERNEL
+        depends on MEMORY_FAILURE && DEBUG_KERNEL && PROC_FS
         select PROC_PAGE_MONITOR
 
 config NOMMU_INITIAL_TRIM_EXCESS
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 6a0466ed5bfd..17299fd4577c 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -52,6 +52,8 @@ int sysctl_memory_failure_recovery __read_mostly = 1;
 
 atomic_long_t mce_bad_pages __read_mostly = ATOMIC_LONG_INIT(0);
 
+#if defined(CONFIG_HWPOISON_INJECT) || defined(CONFIG_HWPOISON_INJECT_MODULE)
+
 u32 hwpoison_filter_enable = 0;
 u32 hwpoison_filter_dev_major = ~0U;
 u32 hwpoison_filter_dev_minor = ~0U;
@@ -164,6 +166,13 @@ int hwpoison_filter(struct page *p)
 
         return 0;
 }
+#else
+int hwpoison_filter(struct page *p)
+{
+        return 0;
+}
+#endif
+
 EXPORT_SYMBOL_GPL(hwpoison_filter);
 
 /*