Re: [PATCH, RESEND] procfs: silence lockdep warning about read vs. exec seq_file

2014-08-05 Thread Kirill A. Shutemov
On Mon, Aug 04, 2014 at 08:42:11PM -0700, Eric W. Biederman wrote: > "Kirill A. Shutemov" writes: > > > From: "Kirill A. Shutemov" > > > > Testcase: > > > > cat /proc/self/maps >/dev/null > > chmod +x /proc/self/net/packet > > exec /proc/self/net/packet > > > > It triggers lockdep warning:

Re: [PATCH, RESEND] procfs: silence lockdep warning about read vs. exec seq_file

2014-08-04 Thread Eric W. Biederman
"Kirill A. Shutemov" writes: > From: "Kirill A. Shutemov" > > Testcase: > > cat /proc/self/maps >/dev/null > chmod +x /proc/self/net/packet > exec /proc/self/net/packet > > It triggers lockdep warning: > I don't know why we allow "chmod +x" on some proc files, notably net-related. > Is it

Re: [PATCH, RESEND] procfs: silence lockdep warning about read vs. exec seq_file

2014-08-03 Thread Oleg Nesterov
Sorry for delay, On 08/02, Kirill A. Shutemov wrote: > > +/* > + * proc_pid_personality() and proc_pid_stack() take cred_guard_mutex via > + * lock_trace() And at first glance they lock_trace() can die. But lets temporary ignore, m_start() is trickier. > +static struct lock_class_key pid_maps_se