çå: ext4 error

[Eric Shang]

Hi Toshi:
	Thanks! I think this not relate to DAX and dax_get_unmapped_area, I am a junior kernel maintainer for our company. This issue bother me long time, looks like kernel ext4 issue or our emmc driver issue, I will dig it out, Thanks!

Best Regards
EricShang


-----éäåä-----
åää: Toshi Kani [mailto:toshi.kani@xxxxxxx] 
åéæé: 2016å4æ13æ 22:10
æää: Eric Shang; Matthew Wilcox
æé: akpm@xxxxxxxxxxxxxxxxxxxx; dan.j.williams@xxxxxxxxx; viro@xxxxxxxxxxxxxxxxxx; ross.zwisler@xxxxxxxxxxxxxxx; kirill.shutemov@xxxxxxxxxxxxxxx; david@xxxxxxxxxxxxx; jack@xxxxxxx; tytso@xxxxxxx; adilger.kernel@xxxxxxxxx; linux-nvdimm@xxxxxxxxxxxx; linux-fsdevel@xxxxxxxxxxxxxxx; linux-ext4@xxxxxxxxxxxxxxx; xfs@xxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
äé: Re: ext4 error

On Wed, 2016-04-13 at 13:44 +0000, Eric Shang wrote:
> HI All:
> Â I meet an ext4 error, following is the error log. After panic, I 
> check the emmc by the tool debufs, the inode 69878 i_nlink is not 
> zero. And this inode don't belong to parent dir 6987, it belong to 
> other file(this inode belong to two files when check by debugfs 
> ncheck), I guess than this inode has beed deleted in memory and 
> already used by other file. But the parent dentry buff_head not flush 
> to emmc. But when lookup this dentry can't find it' in dentry cache, 
> and then lookup_real, read the dentry from emmc, get the file inode which already be deleted.
> Â Can any give me some help how to check this issue. My kernel version 
> is 3.18 form Android . I thinks something wrong with dentry cache 
> flush and dirty buff_head flush to emmc. Thanks all!

Are you somehow using DAX and my dax_get_unmapped_area patches in your Android
3.18 kernel? I doubt this is the case, but I thought I should check since you reported it to me and Matthew with the same cc list.

If you are simply using a distributed Android kernel, you should report it to Android email list or bug tracker.

-Toshi