lkml.org 
[lkml]   [2004]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: deadlocks caused by ext3/reiser dirty_inode calls during do_mmap_pgoff
From
Date
On Tue, 2004-06-22 at 15:05, Andrew Morton wrote:
> Chris Mason <mason@suse.com> wrote:

> > Oh, just realized this will break our data=ordered setup. prepare_write
> > is going to do things like allocating blocks in the file etc etc. If we
> > close the transaction via commit_write(0 size) and crash, we'll leak.
>
> OK, then just zero the pagecache page between `from' and `to' and call
> ->commit_write() with unmodified `from' and `to'?
>
> > We might need to do prefault + pin on the user pages.
>
> That's always been the correct way to fix these problems, but it involves a
> pagetable walk, which requires page_table_lock. Not a popular thing to be
> doing on the write() fastpath.

Fair enough, zeroing between from and to should do it.

-chris


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

\
 
 \ /
  Last update: 2005-03-22 14:04    [W:0.065 / U:0.632 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site