lkml.org 
[lkml]   [2000]   [Dec]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: fs corruption with invalidate_buffers()
On Wed, Dec 06, 2000 at 03:07:23AM +0100, Jan Niehusmann wrote:
> While resizing the filesystem, invalidate_buffers() is called from the
> lvm code. (lvm.c, line 2251, in lvm_do_lv_extend_reduce())
> If I remove this call, the corruption goes away. But this is probably not
> the correct fix, as it can cause problems when reducing the lv size.

Some more details:

I added the following code to put_last_free(bh) in buffer.c:

--- buffer.c.orig Wed Dec 6 17:19:57 2000
+++ buffer.c Thu Dec 7 19:55:39 2000
@@ -500,6 +500,11 @@
struct bh_free_head *head = &free_list[BUFSIZE_INDEX(bh->b_size)];
struct buffer_head **bhp = &head->list;

+ if(bh->b_page && Page_Uptodate(bh->b_page)
+ && bh->b_page->mapping) { // XXX ???
+ BUG();
+ }
+
bh->b_state = 0;

spin_lock(&head->lock);

That is, if I want to put a buffer to the free list, I check if it is
mapped and uptodate. If I understand the memory management correctly, this
is a Bad Thing and should not happen. But guess what? It does, in
invalidate_buffers.

I think invalidate_buffers should check if the buffer belongs to a
mapped page, and if it does, invalidate this mapping.

Jan


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:51    [W:0.061 / U:0.892 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site