Re: corruption

Andrew Morton
2000-12-03T22:12:25Z

Alexander Viro wrote:
>
> On Sun, 3 Dec 2000, Andrew Morton wrote:
>
> > It appears that this problem is not fixed.
>
> Sure, it isn't. Place where the shit hits the fan: fs/buffer.c::unmap_buffer().
> Add the call of remove_inode_queue(bh) there and see if it helps. I.e.
>
> ed fs/buffer.c <<EOF
> /unmap_buffer/
> /}/i
> remove_inode_queue(bh);
> .
> wq
> EOF
>

Sorry, it's still failing. It took three hours.

&inode->i_dirty_buffers=0xca9e63f8
next=0xc30a2598
prev=0xc30a2598
kernel BUG at inode.c:86!

The ksymoops output is here, as is my current diff wrt test12-pre3.

ksymoops 0.7c on i686 2.4.0-test12-pre3. Options used
-V (default)
-k /proc/ksyms (default)
-l /proc/modules (default)
-o /lib/modules/2.4.0-test12-pre3/ (default)
-m /usr/src/linux/System.map (default)

Warning: You did not tell me where to find symbol information. I will
assume that the log matches the kernel and modules that are running
right now and I'll use the default options above for symbol resolution.
If the current kernel and/or modules do not match the log, you can get
more accurate output by telling me the kernel version and where to find
map, modules, ksyms etc. ksymoops -h explains the options.

Reading Oops report from the terminal
Dec 4 01:56:02 mnm kernel: EIP: 0010:[<c0145758>]
Using defaults from ksymoops -t elf32-i386 -a i386
Dec 4 01:56:02 mnm kernel: EFLAGS: 00010282
Dec 4 01:56:02 mnm kernel: eax: 0000001a ebx: ca9e63e0 ecx: 00000001 edx: 00000000
Dec 4 01:56:02 mnm kernel: esi: c025b8a0 edi: cfbcb040 ebp: ce2b0260 esp: ced4df3c
Dec 4 01:56:02 mnm kernel: ds: 0018 es: 0018 ss: 0018
Dec 4 01:56:02 mnm kernel: Process lat_fs (pid: 17559, stackpage=ced4d000) Dec 4 01:56:02 mnm kernel: Stack: c021b845 c021b939 00000056 ca9e63e0 c0146966 ca9e63e0 ce2b0260 ca9e63e0
Dec 4 01:56:02 mnm kernel: Call Trace: [<c021b845>] [<c021b939>] [<c0146966>] [<c01450b6>] [<c013de6d>] [<c013df45>] [<c0108fdf>]
Dec 4 01:56:02 mnm kernel: Code: 0f 0b 83 c4 0c 8d 76 00 53 a1 10 d1 2a c0 50 e8 80 3d fe ff

>>EIP; c0145758 <destroy_inode+48/64> <=====
Trace; c021b845 <tvecs+5a3d/1a418>
Trace; c021b939 <tvecs+5b31/1a418>
Trace; c0146966 <iput+18e/194>
Trace; c01450b6 <d_delete+66/ac>
Trace; c013de6d <vfs_unlink+18d/1c0>
Trace; c013df45 <sys_unlink+a5/118>
Trace; c0108fdf <system_call+33/38>
Code; c0145758 <destroy_inode+48/64>
00000000 <_EIP>:
Code; c0145758 <destroy_inode+48/64> <=====
0: 0f 0b ud2a <=====
Code; c014575a <destroy_inode+4a/64>
2: 83 c4 0c add $0xc,%esp
Code; c014575d <destroy_inode+4d/64>
5: 8d 76 00 lea 0x0(%esi),%esi
Code; c0145760 <destroy_inode+50/64>
8: 53 push %ebx
Code; c0145761 <destroy_inode+51/64>
9: a1 10 d1 2a c0 mov 0xc02ad110,%eax
Code; c0145766 <destroy_inode+56/64>
e: 50 push %eax
Code; c0145767 <destroy_inode+57/64>
f: e8 80 3d fe ff call fffe3d94 <_EIP+0xfffe3d94> c01294ec <kmem_cache_free+0/7c>

1 warning issued. Results may not be reliable.

--- linux-2.4.0-test12-pre3/include/linux/list.h Fri Aug 11 19:06:12 2000
+++ linux-akpm/include/linux/list.h Fri Dec 1 17:31:35 2000
@@ -90,6 +90,7 @@
static __inline__ void list_del(struct list_head *entry)
{
__list_del(entry->prev, entry->next);
+ entry->next = entry->prev = 0;
}

/**
--- linux-2.4.0-test12-pre3/fs/buffer.c Wed Nov 29 18:23:19 2000
+++ linux-akpm/fs/buffer.c Sun Dec 3 22:36:18 2000
@@ -871,10 +871,11 @@
else {
bh->b_inode = &tmp;
list_add(&bh->b_inode_buffers, &tmp.i_dirty_buffers);
- atomic_inc(&bh->b_count);
if (buffer_dirty(bh)) {
+ atomic_inc(&bh->b_count);
spin_unlock(&lru_list_lock);
ll_rw_block(WRITE, 1, &bh);
+ brelse(bh);
spin_lock(&lru_list_lock);
}
}
@@ -883,6 +884,7 @@
while (!list_empty(&tmp.i_dirty_buffers)) {
bh = BH_ENTRY(tmp.i_dirty_buffers.prev);
remove_inode_queue(bh);
+ atomic_inc(&bh->b_count);
spin_unlock(&lru_list_lock);
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
@@ -929,9 +931,9 @@
atomic_inc(&bh->b_count);
spin_unlock(&lru_list_lock);
wait_on_buffer(bh);
- brelse(bh);
if (!buffer_uptodate(bh))
err = -EIO;
+ brelse(bh);
spin_lock(&lru_list_lock);
goto repeat;
}
@@ -1459,6 +1461,9 @@
clear_bit(BH_Mapped, &bh->b_state);
clear_bit(BH_Req, &bh->b_state);
clear_bit(BH_New, &bh->b_state);
+ spin_lock(&lru_list_lock);
+ remove_inode_queue(bh);
+ spin_unlock(&lru_list_lock);
}
}

--- linux-2.4.0-test12-pre3/fs/inode.c Wed Nov 29 18:23:19 2000
+++ linux-akpm/fs/inode.c Sat Dec 2 15:34:51 2000
@@ -77,7 +77,17 @@

#define alloc_inode() \
((struct inode *) kmem_cache_alloc(inode_cachep, SLAB_KERNEL))
-#define destroy_inode(inode) kmem_cache_free(inode_cachep, (inode))
+static void destroy_inode(struct inode *inode)
+{
+ if (!list_empty(&inode->i_dirty_buffers)) {
+ printk("&inode->i_dirty_buffers=0x%p\n", &inode->i_dirty_buffers);
+ printk("next=0x%p\n", inode->i_dirty_buffers.next);
+ printk("prev=0x%p\n", inode->i_dirty_buffers.prev);
+ BUG();
+ }
+ kmem_cache_free(inode_cachep, (inode));
+}
+

/*
* These are initializations that only need to be done
@@ -348,6 +358,12 @@

void clear_inode(struct inode *inode)
{
+ if (!list_empty(&inode->i_dirty_buffers)) {
+ if (inode->i_nlink)
+ BUG();
+ invalidate_inode_buffers(inode);
+ }
+
if (inode->i_data.nrpages)
BUG();
if (!(inode->i_state & I_FREEING))
@@ -407,6 +423,7 @@
inode = list_entry(tmp, struct inode, i_list);
if (inode->i_sb != sb)
continue;
+ invalidate_inode_buffers(inode);
if (!atomic_read(&inode->i_count)) {
list_del(&inode->i_hash);
INIT_LIST_HEAD(&inode->i_hash);