path: root/mm/memory-failure.c
diff options
authorTony Luck <tony.luck@intel.com>2012-07-11 10:20:47 -0700
committerTony Luck <tony.luck@intel.com>2012-07-11 10:20:47 -0700
commit6751ed65dc6642af64f7b8a440a75563c8aab7ae (patch)
tree8736d4c2b3aa00c6a4f39d2e6cba4805720c2874 /mm/memory-failure.c
parent6887a4131da3adaab011613776d865f4bcfb5678 (diff)
x86/mce: Fix siginfo_t->si_addr value for non-recoverable memory faults
In commit dad1743e5993f1 ("x86/mce: Only restart instruction after machine check recovery if it is safe") we fixed mce_notify_process() to force a signal to the current process if it was not restartable (RIPV bit not set in MCG_STATUS). But doing it here means that the process doesn't get told the virtual address of the fault via siginfo_t->si_addr. This would prevent application level recovery from the fault. Make a new MF_MUST_KILL flag bit for memory_failure() et al. to use so that we will provide the right information with the signal. Signed-off-by: Tony Luck <tony.luck@intel.com> Acked-by: Borislav Petkov <borislav.petkov@amd.com> Cc: stable@kernel.org # 3.4+
Diffstat (limited to 'mm/memory-failure.c')
1 files changed, 8 insertions, 6 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index ab1e7145e29..de4ce705845 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -345,14 +345,14 @@ static void add_to_kill(struct task_struct *tsk, struct page *p,
* Also when FAIL is set do a force kill because something went
* wrong earlier.
-static void kill_procs(struct list_head *to_kill, int doit, int trapno,
+static void kill_procs(struct list_head *to_kill, int forcekill, int trapno,
int fail, struct page *page, unsigned long pfn,
int flags)
struct to_kill *tk, *next;
list_for_each_entry_safe (tk, next, to_kill, nd) {
- if (doit) {
+ if (forcekill) {
* In case something went wrong with munmapping
* make sure the process doesn't catch the
@@ -858,7 +858,7 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
struct address_space *mapping;
int ret;
- int kill = 1;
+ int kill = 1, forcekill;
struct page *hpage = compound_head(p);
struct page *ppage;
@@ -888,7 +888,7 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
* be called inside page lock (it's recommended but not enforced).
mapping = page_mapping(hpage);
- if (!PageDirty(hpage) && mapping &&
+ if (!(flags & MF_MUST_KILL) && !PageDirty(hpage) && mapping &&
mapping_cap_writeback_dirty(mapping)) {
if (page_mkclean(hpage)) {
@@ -965,12 +965,14 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
* Now that the dirty bit has been propagated to the
* struct page and all unmaps done we can decide if
* killing is needed or not. Only kill when the page
- * was dirty, otherwise the tokill list is merely
+ * was dirty or the process is not restartable,
+ * otherwise the tokill list is merely
* freed. When there was a problem unmapping earlier
* use a more force-full uncatchable kill to prevent
* any accesses to the poisoned memory.
- kill_procs(&tokill, !!PageDirty(ppage), trapno,
+ forcekill = PageDirty(ppage) || (flags & MF_MUST_KILL);
+ kill_procs(&tokill, forcekill, trapno,
ret != SWAP_SUCCESS, p, pfn, flags);
return ret;