From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Yan, Zheng " Subject: Re: bug caused by removal of trans_mutex? (Was: Re: kernel BUG at fs/btrfs/extent-tree.c:6164!) Date: Tue, 14 Jun 2011 14:53:26 +0800 Message-ID: References: <4DEC90CB.4050609@jp.fujitsu.com> <4DEDB7AF.2060308@cn.fujitsu.com> <4DEDBE4B.2020403@jp.fujitsu.com> <4DEDC293.30105@jp.fujitsu.com> <4DEDE03B.9050907@jp.fujitsu.com> <4DEDE328.5060405@cn.fujitsu.com> <1307461229-sup-9822@shiny> <4DEF04CF.8010502@jp.fujitsu.com> <4DF5B889.5080202@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Tsutomu Itoh , Chris Mason , liubo , Linux Btrfs , Josef Bacik To: Li Zefan Return-path: In-Reply-To: <4DF5B889.5080202@cn.fujitsu.com> List-ID: I found another bug. There are codes (btrfs_save_ino_cache) that modify fs trees after create_pending_snapshots is called. This can corrupt your fs. On Mon, Jun 13, 2011 at 3:13 PM, Li Zefan wrote: > Cc: Josef > >>>>>>>>> I encountered following panic using 'btrfs-unstable + for-lin= us' >>>>>>>>> kernel. >>>>>>>>> >>>>>>>>> I ran "btrfs fi bal /test5" command, and mount option of /tes= t5 >>>>>>>>> is as follows: >>>>>>>>> >>>>>>>>> =A0/dev/sdc3 on /test5 type btrfs (rw,space_cache,compress=3D= lzo,inode_cache) >>>>>>>>> >>>>>>>> So, just a "btrfs fi bal" would lead to the bug? >>>>>>> I think so. >>> >>> It should be specific to the inode caching code. =A0The balancing c= ode is >>> finding the inode map cache extents, but it doesn't know how to rel= ocate >>> them. >> >> However, the panic has occurred even if inode_cahce is turned off. >> Is this another problem? >> > > I don't think free inode cache isthe cause of the bug here (even if i= node_cache > is turned on). > > What I have found out is: > > 1. git checkout a4abeea41adfa3c143c289045f4625dfaeba2212 > > So the top commit is the removal of trans_mutex and no delayed_inode = patch > or free inode cache patchset in the tree, and bug can be triggered. > > 2. git checkout 2a1eb4614d984d5cd4c928784e9afcf5c07f93be > > So the top commit is the one before trans_mutex removal, and no bug t= riggered. > > 3. test linus' tree > > bug triggered. > > 4. revert that suspicoius commit manually from linus' tree > > no bug. > > so either that commit is buggy or it reveals some bugs covered by the= trans_mutex. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs= " in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html