HWPOISON: Report correct address granuality for AO huge page errors

The SIGBUS user space signalling is supposed to report the
address granuality of a corruption. Pass this information correctly
for huge pages by querying the hpage order.

Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 9c26eeca1342..cd7e6974de77 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -183,7 +183,7 @@ EXPORT_SYMBOL_GPL(hwpoison_filter);
  * signal.
  */
 static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
-                        unsigned long pfn)
+                        unsigned long pfn, struct page *page)
 {
         struct siginfo si;
         int ret;
@@ -198,7 +198,7 @@ static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
 #ifdef __ARCH_SI_TRAPNO
         si.si_trapno = trapno;
 #endif
-        si.si_addr_lsb = PAGE_SHIFT;
+        si.si_addr_lsb = compound_order(compound_head(page)) + PAGE_SHIFT;
         /*
          * Don't use force here, it's convenient if the signal
          * can be temporarily blocked.
@@ -327,7 +327,7 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
  * wrong earlier.
  */
 static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
-                          int fail, unsigned long pfn)
+                          int fail, struct page *page, unsigned long pfn)
 {
         struct to_kill *tk, *next;
 
@@ -352,7 +352,7 @@ static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
                          * process anyways.
                          */
                         else if (kill_proc_ao(tk->tsk, tk->addr, trapno,
-                                              pfn) < 0)
+                                              pfn, page) < 0)
                                 printk(KERN_ERR
                 "MCE %#lx: Cannot send advisory machine check signal to %s:%d\n",
                                         pfn, tk->tsk->comm, tk->tsk->pid);
@@ -928,7 +928,7 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
          * any accesses to the poisoned memory.
          */
         kill_procs_ao(&tokill, !!PageDirty(hpage), trapno,
-                      ret != SWAP_SUCCESS, pfn);
+                      ret != SWAP_SUCCESS, p, pfn);
 
         return ret;
 }