Re: [PATCH] ext4: Fix deadlock on page reclaim

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sat, Jul 27, 2019 at 08:44:23AM +1000, Dave Chinner wrote:
> > 
> > This looks like something that could hit every file systems, so
> > shouldn't we fix this in common code?  We could also look into
> > just using memalloc_nofs_save for the page cache allocation path
> > instead of the per-mapping gfp_mask.
> 
> I think it has to be the entire IO path - any allocation from the
> underlying filesystem could recurse into the top level filesystem
> and then deadlock if the memory reclaim submits IO or blocks on
> IO completion from the upper filesystem. That's a bloody big hammer
> for something that is only necessary when there are stacked
> filesystems like this....

Yeah.... that's why using memalloc_nofs_save() probably makes the most
sense, and dm_zoned should use that before it calls into ext4.

       	   	    	       	    	   - Ted



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux