At present, I found some kernel message like:
LUB raid5-md127: kmem_cache_destroy called for cache that still has objects.
Pid: 6143, comm: mdadm Tainted: G O 3.4.0-rc6+ #75
Call Trace:
[<ffffffff811227f8>] kmem_cache_destroy+0x328/0x400
[<ffffffffa005ff1d>] free_conf+0x2d/0xf0 [raid456]
[<ffffffffa0060791>] stop+0x41/0x60 [raid456]
[<ffffffffa000276a>] md_stop+0x1a/0x60 [md_mod]
[<ffffffffa000c974>] do_md_stop+0x74/0x470 [md_mod]
[<ffffffffa000d0ff>] md_ioctl+0xff/0x11f0 [md_mod]
[<ffffffff8127c958>] blkdev_ioctl+0xd8/0x7a0
[<ffffffff8115ef6b>] block_ioctl+0x3b/0x40
[<ffffffff8113b9c6>] do_vfs_ioctl+0x96/0x560
[<ffffffff8113bf21>] sys_ioctl+0x91/0xa0
[<ffffffff816e9d22>] system_call_fastpath+0x16/0x1b
Then using kmemleak can found those messages:
unreferenced object 0xffff8800b6db7380 (size 112):
comm "mdadm", pid 5783, jiffies 4294810749 (age 90.589s)
hex dump (first 32 bytes):
01 01 db b6 ad 4e ad de ff ff ff ff ff ff ff ff .....N..........
ff ff ff ff ff ff ff ff 98 40 4a 82 ff ff ff ff .........@J.....
backtrace:
[<ffffffff816b52c1>] kmemleak_alloc+0x21/0x50
[<ffffffff8111a11b>] kmem_cache_alloc+0xeb/0x1b0
[<ffffffff8111c431>] kmem_cache_open+0x2f1/0x430
[<ffffffff8111c6c8>] kmem_cache_create+0x158/0x320
[<ffffffffa008f979>] setup_conf+0x649/0x770 [raid456]
[<ffffffffa009044b>] run+0x68b/0x840 [raid456]
[<ffffffffa000bde9>] md_run+0x529/0x940 [md_mod]
[<ffffffffa000c218>] do_md_run+0x18/0xc0 [md_mod]
[<ffffffffa000dba8>] md_ioctl+0xba8/0x11f0 [md_mod]
[<ffffffff81272b28>] blkdev_ioctl+0xd8/0x7a0
[<ffffffff81155bfb>] block_ioctl+0x3b/0x40
[<ffffffff811326d6>] do_vfs_ioctl+0x96/0x560
[<ffffffff81132c31>] sys_ioctl+0x91/0xa0
[<ffffffff816dd3a2>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
Because kmemleak don't detect page leak, so the pages of slabs did not print.
Commit a8364d5555b2030d093cde0f0795 modify the code of flush_all.
Signed-off-by: majianpeng <majianpeng@xxxxxxxxx>
---
mm/slub.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index ffe13fd..6fce08f 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2040,7 +2040,7 @@ static bool has_cpu_slab(int cpu, void *info)
struct kmem_cache *s = info;
struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
- return !!(c->page);
+ return !!c;
}
static void flush_all(struct kmem_cache *s)
--
1.7.5.4
root@majianpeng:/mnt/kernel/linux# vim mm/slub.c
root@majianpeng:/mnt/kernel/linux# cat 0001-slub-Using-judgement-c-to-judge-per-cpu-has-obj-in-f.patch
>From 450d4eb2ba950e5b0161f872c02a9ec36afafa82 Mon Sep 17 00:00:00 2001
From: majianpeng <majianpeng@xxxxxxxxx>
Date: Mon, 7 May 2012 20:38:41 +0800
Subject: [PATCH] slub: Using judgement !!c to judge per cpu has obj in
fucntion has_cpu_slab().
At present, I found some kernel message like:
LUB raid5-md127: kmem_cache_destroy called for cache that still has objects.
Pid: 6143, comm: mdadm Tainted: G O 3.4.0-rc6+ #75
Call Trace:
[<ffffffff811227f8>] kmem_cache_destroy+0x328/0x400
[<ffffffffa005ff1d>] free_conf+0x2d/0xf0 [raid456]
[<ffffffffa0060791>] stop+0x41/0x60 [raid456]
[<ffffffffa000276a>] md_stop+0x1a/0x60 [md_mod]
[<ffffffffa000c974>] do_md_stop+0x74/0x470 [md_mod]
[<ffffffffa000d0ff>] md_ioctl+0xff/0x11f0 [md_mod]
[<ffffffff8127c958>] blkdev_ioctl+0xd8/0x7a0
[<ffffffff8115ef6b>] block_ioctl+0x3b/0x40
[<ffffffff8113b9c6>] do_vfs_ioctl+0x96/0x560
[<ffffffff8113bf21>] sys_ioctl+0x91/0xa0
[<ffffffff816e9d22>] system_call_fastpath+0x16/0x1b
Then using kmemleak can found those messages:
unreferenced object 0xffff8800b6db7380 (size 112):
comm "mdadm", pid 5783, jiffies 4294810749 (age 90.589s)
hex dump (first 32 bytes):
01 01 db b6 ad 4e ad de ff ff ff ff ff ff ff ff .....N..........
ff ff ff ff ff ff ff ff 98 40 4a 82 ff ff ff ff .........@J.....
backtrace:
[<ffffffff816b52c1>] kmemleak_alloc+0x21/0x50
[<ffffffff8111a11b>] kmem_cache_alloc+0xeb/0x1b0
[<ffffffff8111c431>] kmem_cache_open+0x2f1/0x430
[<ffffffff8111c6c8>] kmem_cache_create+0x158/0x320
[<ffffffffa008f979>] setup_conf+0x649/0x770 [raid456]
[<ffffffffa009044b>] run+0x68b/0x840 [raid456]
[<ffffffffa000bde9>] md_run+0x529/0x940 [md_mod]
[<ffffffffa000c218>] do_md_run+0x18/0xc0 [md_mod]
[<ffffffffa000dba8>] md_ioctl+0xba8/0x11f0 [md_mod]
[<ffffffff81272b28>] blkdev_ioctl+0xd8/0x7a0
[<ffffffff81155bfb>] block_ioctl+0x3b/0x40
[<ffffffff811326d6>] do_vfs_ioctl+0x96/0x560
[<ffffffff81132c31>] sys_ioctl+0x91/0xa0
[<ffffffff816dd3a2>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
Because kmemleak don't detect page leak, so the pages of slabs did not print.
Commit a8364d5555b2030d093cde0f0795 modify the code of flush_all.
Signed-off-by: majianpeng <majianpeng@xxxxxxxxx>
---
mm/slub.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/mm/slub.c b/mm/slub.c
index ffe13fd..6fce08f 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2040,7 +2040,7 @@ static bool has_cpu_slab(int cpu, void *info)
struct kmem_cache *s = info;
struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
- return !!(c->page);
+ return !!c;
}
static void flush_all(struct kmem_cache *s)
--
1.7.5.4
--------------
majianpeng
2012-05-08
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