David Sterba wrote on 2016/04/01 10:44 +0200:
On Fri, Apr 01, 2016 at 08:28:18AM +0800, Qu Wenruo wrote:
David Sterba wrote on 2016/03/31 18:30 +0200:
On Thu, Mar 31, 2016 at 10:19:34AM +0800, Qu Wenruo wrote:
At least 2 user from mail list reported btrfsck reported false alert of
"bad metadata [XXXX,YYYY) crossing stripe boundary".
While the reported number are all inside the same 64K boundary.
After some check, all the false alert have the same bytenr feature,
which can be divided by stripe size (64K).
The result seems to be initial 'max_size' can be 0, causing 'start' +
'max_size' - 1, to cross the stripe boundary.
Fix it by always update extent_record->cross_stripe when the
extent_record is updated, to avoid temporary false alert to be reported.
Signed-off-by: Qu Wenruo <quwenruo@xxxxxxxxxxxxxx>
Applied, thanks.
Do you have a test image for that?
Unfortunately, no.
Although I figured out the cause the the false alert, I still didn't
find a image/method to reproduce it, except the images of reporters.
I can dig a little further trying to make a image.
After another look, why don't we use nodesize directly? Or stripesize
where applies. With max_size == 0 the test does not make sense, we ought
to know the alignment.
Yes, my first though is also to use nodesize directly, which should be
always correct.
But the problem is, the related function call stack doesn't have any
member to reach btrfs_root or btrfs_fs_info.
In the very beginning version of such crossing stripe check, I used to
add a btrfs_root/btrfs_fs_info parameter to the function.
But the code change are too many, so I use 'max_size'.
I can try to re-do such modification, but IIRC it didn't cause a good
result.
Thanks,
Qu
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