On 19/03/15 12:10, Iurii Konovalenko wrote: > Hi, guys! > > When I read, that I am not alone and that issue depends on kernel > version, I decided to continue investigation. > And I found why our threads locks on read/write operations. > On Linux kernel 3.14+ syscalls of file read and write changed a bit: > fdget() function was replaced by fdget_pos() - it is fdget() function > plus additional position mutex lock for files with FMODE_ATOMIC_POS > (files for inodes with S_IFREG flag set - regular nodes). As I thought > our xen files are not regular and nonseekable, I hoped this flag is > not set. But it is set. It is because our file system is created by > function simple_fill_super(), and inside it this flag is hardly set: > inode->i_mode = S_IFREG | files->mode; > So, as a fast hack I made a patch: just made copy of this function for > xen, which does not set this flag. It works for me. Could you please > check if it works for you.
I still can't get this to deadlock, but why not clear FMODE_ATOMIC_POS in xenbus_file_open() ? David _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
