[nacked] mm-slub-introduce-slab_warn_on_error.patch removed from -mm tree

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The patch titled
     Subject: mm/slub: introduce SLAB_WARN_ON_ERROR
has been removed from the -mm tree.  Its filename was
     mm-slub-introduce-slab_warn_on_error.patch

This patch was dropped because it was nacked

------------------------------------------------------
From: Miles Chen <miles.chen@xxxxxxxxxxxx>
Subject: mm/slub: introduce SLAB_WARN_ON_ERROR

When debugging slab errors in slub.c, sometimes we have to trigger a panic
in order to get the coredump file.  Add a debug option SLAB_WARN_ON_ERROR
to toggle WARN_ON() when the option is set.

[akpm@xxxxxxxxxxxxxxxxxxxx: Documentation/vm/slub.rst: avoid misleading use of the word "toggle"]
Link: http://lkml.kernel.org/r/1548313223-17114-1-git-send-email-miles.chen@xxxxxxxxxxxx
Signed-off-by: Miles Chen <miles.chen@xxxxxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Christopher Lameter <cl@xxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>,
Cc: David Rientjes <rientjes@xxxxxxxxxx>,
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>,
Cc: Jonathan Corbet <corbet@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 Documentation/vm/slub.rst |    3 ++-
 include/linux/slab.h      |    3 +++
 mm/slub.c                 |   34 ++++++++++++++++++++++++++++++++--
 3 files changed, 37 insertions(+), 3 deletions(-)

--- a/Documentation/vm/slub.rst~mm-slub-introduce-slab_warn_on_error
+++ a/Documentation/vm/slub.rst
@@ -49,9 +49,10 @@ Possible debug options are::
 	P		Poisoning (object and padding)
 	U		User tracking (free and alloc)
 	T		Trace (please only use on single slabs)
-	A		Toggle failslab filter mark for the cache
+	A		Enable/disable failslab filter mark for the cache
 	O		Switch debugging off for caches that would have
 			caused higher minimum slab orders
+	W		Enable/disable WARN_ON() on slab errors
 	-		Switch all debugging off (useful if the kernel is
 			configured with CONFIG_SLUB_DEBUG_ON)
 
--- a/include/linux/slab.h~mm-slub-introduce-slab_warn_on_error
+++ a/include/linux/slab.h
@@ -109,6 +109,9 @@
 #define SLAB_KASAN		0
 #endif
 
+/* WARN_ON slab error */
+#define SLAB_WARN_ON_ERROR	((slab_flags_t __force)0x10000000U)
+
 /* The following flags affect the page allocator grouping pages by mobility */
 /* Objects are reclaimable */
 #define SLAB_RECLAIM_ACCOUNT	((slab_flags_t __force)0x00020000U)
--- a/mm/slub.c~mm-slub-introduce-slab_warn_on_error
+++ a/mm/slub.c
@@ -691,7 +691,10 @@ static void print_trailer(struct kmem_ca
 		print_section(KERN_ERR, "Padding ", p + off,
 			      size_from_object(s) - off);
 
-	dump_stack();
+	if (unlikely(s->flags & SLAB_WARN_ON_ERROR))
+		WARN_ON(1);
+	else
+		dump_stack();
 }
 
 void object_err(struct kmem_cache *s, struct page *page,
@@ -712,7 +715,11 @@ static __printf(3, 4) void slab_err(stru
 	va_end(args);
 	slab_bug(s, "%s", buf);
 	print_page_info(page);
-	dump_stack();
+
+	if (unlikely(s->flags & SLAB_WARN_ON_ERROR))
+		WARN_ON(1);
+	else
+		dump_stack();
 }
 
 static void init_object(struct kmem_cache *s, void *object, u8 val)
@@ -1271,6 +1278,9 @@ static int __init setup_slub_debug(char
 		case 'a':
 			slub_debug |= SLAB_FAILSLAB;
 			break;
+		case 'w':
+			slub_debug |= SLAB_WARN_ON_ERROR;
+			break;
 		case 'o':
 			/*
 			 * Avoid enabling debugging on caches if its minimum
@@ -5238,6 +5248,25 @@ static ssize_t store_user_store(struct k
 }
 SLAB_ATTR(store_user);
 
+static ssize_t warn_on_error_show(struct kmem_cache *s, char *buf)
+{
+	return sprintf(buf, "%d\n", !!(s->flags & SLAB_WARN_ON_ERROR));
+}
+
+static ssize_t warn_on_error_store(struct kmem_cache *s,
+				const char *buf, size_t length)
+{
+	if (any_slab_objects(s))
+		return -EBUSY;
+
+	s->flags &= ~SLAB_WARN_ON_ERROR;
+	if (buf[0] == '1')
+		s->flags |= SLAB_WARN_ON_ERROR;
+
+	return length;
+}
+SLAB_ATTR(warn_on_error);
+
 static ssize_t validate_show(struct kmem_cache *s, char *buf)
 {
 	return 0;
@@ -5446,6 +5475,7 @@ static struct attribute *slab_attrs[] =
 	&validate_attr.attr,
 	&alloc_calls_attr.attr,
 	&free_calls_attr.attr,
+	&warn_on_error_attr.attr,
 #endif
 #ifdef CONFIG_ZONE_DMA
 	&cache_dma_attr.attr,
_

Patches currently in -mm which might be from miles.chen@xxxxxxxxxxxx are





[Index of Archives]     [Kernel Archive]     [IETF Annouce]     [DCCP]     [Netdev]     [Networking]     [Security]     [Bugtraq]     [Yosemite]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux SCSI]

  Powered by Linux