/*
* Common low level (register) ptrace helpers
*
* Copyright 2004-2011 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#ifndef __ASM_GENERIC_PTRACE_H__
#define __ASM_GENERIC_PTRACE_H__
#ifndef __ASSEMBLY__
/* Helpers for working with the instruction pointer */
#ifndef GET_IP
#define GET_IP(regs) ((regs)->pc)
#endif
#ifndef SET_IP
#define SET_IP(regs, val) (GET_IP(regs) = (val))
#endif
static inline unsigned long instruction_pointer(struct pt_regs *regs)
{
return GET_IP(regs);
}
static inline void instruction_pointer_set(struct pt_regs *regs,
unsigned long val)
{
SET_IP(regs, val);
}
#ifndef profile_pc
#define profile_pc(regs) instruction_pointer(regs)
#endif
/* Helpers for working with the user stack pointer */
#ifndef GET_USP
#define GET_USP(regs) ((regs)->usp)
#endif
#ifndef SET_USP
#define SET_USP(regs, val) (GET_USP(regs) = (val))
#endif
static inline unsigned long user_stack_pointer(struct pt_regs *regs)
{
return GET_USP(regs);
}
static inline void user_stack_pointer_set(struct pt_regs *regs,
unsigned long val)
{
SET_USP(regs, val);
}
/* Helpers for working with the frame pointer */
#ifndef GET_FP
#define GET_FP(regs) ((regs)->fp)
#endif
#ifndef SET_FP
#define SET_FP(regs, val) (GET_FP(regs) = (val))
#endif
static inline unsigned long frame_pointer(struct pt_regs *regs)
{
return GET_FP(regs);
}
static inline void frame_pointer_set(struct pt_regs *regs,
unsigned long val)
{
SET_FP(regs, val);
}
#endif /* __ASSEMBLY__ */
#endif
private-remove'>summaryrefslogtreecommitdiff
pid: fix lockdep deadlock warning due to ucount_lock
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.10.0-rc2-00024-g4aecec9-dirty #118 Tainted: G W
---------------------------------------------------------
swapper/1/0 just changed the state of lock:
(&(&sighand->siglock)->rlock){-.....}, at: [<ffffffffbd0a1bc6>] __lock_task_sighand+0xb6/0x2c0
but this lock took another, HARDIRQ-unsafe lock in the past:
(ucounts_lock){+.+...}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Chain exists of: &(&sighand->siglock)->rlock --> &(&tty->ctrl_lock)->rlock --> ucounts_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(ucounts_lock);
local_irq_disable();
lock(&(&sighand->siglock)->rlock);
lock(&(&tty->ctrl_lock)->rlock);
<Interrupt>
lock(&(&sighand->siglock)->rlock);
*** DEADLOCK ***
This patch removes a dependency between rlock and ucount_lock.
Fixes: f333c700c610 ("pidns: Add a limit on the number of pid namespaces")
Cc: stable@vger.kernel.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>