On Mon, Feb 29, 2016 at 7:19 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > On Mon, Feb 29, 2016 at 5:19 PM, Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: >> On Mon, Feb 29, 2016 at 04:54:54PM +0100, Dmitry Vyukov wrote: >> >>> Regardless of whether reordering is wrong or not, do we see how it can >>> fix the WARNINGs/oopses? Because it does seem to. I've tried to revert >>> just this part: >>> >>> - *inode = d_backing_inode(dentry); >>> negative = d_is_negative(dentry); >>> + *inode = d_backing_inode(dentry); >>> >>> And got: >>> >>> [ 976.609688] WARNING: CPU: 0 PID: 12126 at fs/namei.c:1587 >>> lookup_fast+0x3fa/0x450() >>> [ 976.626768] WARNING: CPU: 0 PID: 12126 at fs/namei.c:3123 >>> path_openat+0x12bc/0x1520() >>> >>> in 15 minutes. >> >> dentry going from negative to positive lookup_fast() >> fetch NULL ->d_inode >> store non-NULL ->d_inode >> store new ->d_flags >> fetch new ->d_flags >> check ->d_seq >> bump ->d_seq by 2 >> >> Change the order of fetches and you'll get rid of that scenario. >> >>> In particular, applying this on top the previous patch will be >>> inconclusive, because I already don't see the warnings. >> >> Apply it with that reordering reversed, please. > > > OK, just wanted to make sure that we keep track of the situation. > Restarted testing with combined patch. Here is it just in case: > https://gist.githubusercontent.com/dvyukov/67fe363d5ce2e2b06c71/raw/4d1b6c23f8dff7e0f8e2e3cab7e50208fddb0570/gistfile1.txt No warnings/crashes in 15 hours on 3 VMs! -- 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
