[PATCH 3/4] HWPOISON: Report correct address granuality for AO huge page errors

Andi Kleen
2010-10-06T20:49:35Z

From: Andi Kleen <ak@linux.intel.com>

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.

Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: fengguang.wu@intel.com
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
mm/memory-failure.c | 15 +++++++++------
1 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 9c26eec..886144b 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -183,10 +183,11 @@ 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;
+ unsigned order;

printk(KERN_ERR
"MCE %#lx: Killing %s:%d early due to hardware memory corruption\n",
@@ -198,7 +199,8 @@ 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;
+ order = PageCompound(page) ? huge_page_order(page) : PAGE_SHIFT;
+ si.si_addr_lsb = order;
/*
* Don't use force here, it's convenient if the signal
* can be temporarily blocked.
@@ -327,7 +329,7 @@ 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;

@@ -341,7 +343,8 @@ static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
if (fail || tk->addr_valid == 0) {
printk(KERN_ERR
"MCE %#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
- pfn, tk->tsk->comm, tk->tsk->pid);
+ pfn,
+ tk->tsk->comm, tk->tsk->pid);
force_sig(SIGKILL, tk->tsk);
}

@@ -352,7 +355,7 @@ 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 +931,7 @@ 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;
}
--
1.7.1