[PATCH 1/2] hwpoison: fix hugetlbfs/thp precheck in hwpoison_user_mappings()

[PATCH 1/2] hwpoison: fix hugetlbfs/thp precheck in hwpoison_user_mappings()

[Naoya Horiguchi]

Recent fix from Chen Yucong (commit 0bc1f8b0682c "hwpoison: fix the handling
path of the victimized page frame that belong to non-LRU") rejects going
into unmapping operation for hugetlbfs/thp pages, which results in failing
error containing on such pages. This patch fixes it.

With this patch, hwpoison functional tests in mce-test testsuite pass.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
---
 mm/memory-failure.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git mmotm-2014-07-22-15-58.orig/mm/memory-failure.c mmotm-2014-07-22-15-58/mm/memory-failure.c
index e3e2f007946e..f465b98d0209 100644
--- mmotm-2014-07-22-15-58.orig/mm/memory-failure.c
+++ mmotm-2014-07-22-15-58/mm/memory-failure.c
@@ -895,7 +895,13 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	struct page *hpage = *hpagep;
 	struct page *ppage;
 
-	if (PageReserved(p) || PageSlab(p) || !PageLRU(p))
+	/*
+	 * Here we are interested only in user-mapped pages, so skip any
+	 * other types of pages.
+	 */
+	if (PageReserved(p) || PageSlab(p))
+		return SWAP_SUCCESS;
+	if (!(PageLRU(hpage) || PageHuge(p)))
 		return SWAP_SUCCESS;
 
 	/*
-- 
1.9.3

[PATCH 1/2] hwpoison: fix hugetlbfs/thp precheck in hwpoison_user_mappings()

[Naoya Horiguchi]

Recent fix from Chen Yucong (commit 0bc1f8b0682c "hwpoison: fix the handling
path of the victimized page frame that belong to non-LRU") rejects going
into unmapping operation for hugetlbfs/thp pages, which results in failing
error containing on such pages. This patch fixes it.

With this patch, hwpoison functional tests in mce-test testsuite pass.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
---
 mm/memory-failure.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git mmotm-2014-07-22-15-58.orig/mm/memory-failure.c mmotm-2014-07-22-15-58/mm/memory-failure.c
index e3e2f007946e..f465b98d0209 100644
--- mmotm-2014-07-22-15-58.orig/mm/memory-failure.c
+++ mmotm-2014-07-22-15-58/mm/memory-failure.c
@@ -895,7 +895,13 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	struct page *hpage = *hpagep;
 	struct page *ppage;
 
-	if (PageReserved(p) || PageSlab(p) || !PageLRU(p))
+	/*
+	 * Here we are interested only in user-mapped pages, so skip any
+	 * other types of pages.
+	 */
+	if (PageReserved(p) || PageSlab(p))
+		return SWAP_SUCCESS;
+	if (!(PageLRU(hpage) || PageHuge(p)))
 		return SWAP_SUCCESS;
 
 	/*
-- 
1.9.3

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[PATCH 2/2] hwpoison: call action_result() in failure path of hwpoison_user_mappings()

[Naoya Horiguchi]

hwpoison_user_mappings() could fail for various reasons, so printk()s
to print out the reasons should be done in each failure check inside
hwpoison_user_mappings().
And currently we don't call action_result() when hwpoison_user_mappings()
fails, which is not consistent with other exit points of memory error
handler. So this patch fixes these messaging problems.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
---
 mm/memory-failure.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git mmotm-2014-07-22-15-58.orig/mm/memory-failure.c mmotm-2014-07-22-15-58/mm/memory-failure.c
index f465b98d0209..44c6bd201d3a 100644
--- mmotm-2014-07-22-15-58.orig/mm/memory-failure.c
+++ mmotm-2014-07-22-15-58/mm/memory-failure.c
@@ -911,8 +911,10 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	if (!page_mapped(hpage))
 		return SWAP_SUCCESS;
 
-	if (PageKsm(p))
+	if (PageKsm(p)) {
+		pr_err("MCE %#lx: can't handle KSM pages.\n", pfn);
 		return SWAP_FAIL;
+	}
 
 	if (PageSwapCache(p)) {
 		printk(KERN_ERR
@@ -1245,7 +1247,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	 */
 	if (hwpoison_user_mappings(p, pfn, trapno, flags, &hpage)
 	    != SWAP_SUCCESS) {
-		printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
+		action_result(pfn, "unmapping failed", IGNORED);
 		res = -EBUSY;
 		goto out;
 	}
-- 
1.9.3

[PATCH 2/2] hwpoison: call action_result() in failure path of hwpoison_user_mappings()

[Naoya Horiguchi]

hwpoison_user_mappings() could fail for various reasons, so printk()s
to print out the reasons should be done in each failure check inside
hwpoison_user_mappings().
And currently we don't call action_result() when hwpoison_user_mappings()
fails, which is not consistent with other exit points of memory error
handler. So this patch fixes these messaging problems.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
---
 mm/memory-failure.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git mmotm-2014-07-22-15-58.orig/mm/memory-failure.c mmotm-2014-07-22-15-58/mm/memory-failure.c
index f465b98d0209..44c6bd201d3a 100644
--- mmotm-2014-07-22-15-58.orig/mm/memory-failure.c
+++ mmotm-2014-07-22-15-58/mm/memory-failure.c
@@ -911,8 +911,10 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	if (!page_mapped(hpage))
 		return SWAP_SUCCESS;
 
-	if (PageKsm(p))
+	if (PageKsm(p)) {
+		pr_err("MCE %#lx: can't handle KSM pages.\n", pfn);
 		return SWAP_FAIL;
+	}
 
 	if (PageSwapCache(p)) {
 		printk(KERN_ERR
@@ -1245,7 +1247,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	 */
 	if (hwpoison_user_mappings(p, pfn, trapno, flags, &hpage)
 	    != SWAP_SUCCESS) {
-		printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
+		action_result(pfn, "unmapping failed", IGNORED);
 		res = -EBUSY;
 		goto out;
 	}
-- 
1.9.3

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