On Fri, Apr 10, 2009 at 9:01 AM, Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > On Fri, Apr 10, 2009 at 08:31:40AM -0700, Curt Wohlgemuth wrote: >> This patch fixes a race between a task creating a new inode, and one writing >> that same new, dirty inode out to disk. >> >> We found this using a particular workload (fsstress) along with other >> ancillary processes running on the same machine. The symptom is one or more >> hung unkillable (uniterruptible sleep) tasks that try to operate on this new >> inode. >> >> The original comment block is wrong. Since the inode gets marked dirty >> after it's created, but before its I_LOCK bit is cleared, there _can_ be >> somebody else doing something with this inode -- e.g., a writeback task >> (in our case, __sync_single_inode()). > > Um... I'd say that the real bug in there is that we shouldn't *get* to > __sync_single_inode() until I_NEW/I_LOCK are removed. Well, I thought about that too. But I haven't seen an issue with this happening, and the patch I mailed has the benefit of extreme simplicity. Plus I couldn't be sure that there weren't other spots that assume taking the inode lock meant that they could manipulate the i_state field with confidence (though I didn't find any). Curt -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
