| Message ID | 20220518225355.784371-16-ebiederm@xmission.com |
|---|---|
| State | New |
| Headers | show |
| Series | ptrace: cleanups and calling do_cldstop with only siglock | expand |
Hi "Eric,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on next-20220518]
[cannot apply to linux/master powerpc/next wireless-next/main wireless/main linus/master v5.18-rc7 v5.18-rc6 v5.18-rc5 v5.18-rc7]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/Eric-W-Biederman/signal-alpha-Remove-unused-definition-of-TASK_REAL_PARENT/20220519-065947
base: 736ee37e2e8eed7fe48d0a37ee5a709514d478b3
config: parisc-randconfig-s032-20220519 (https://download.01.org/0day-ci/archive/20220521/202205210010.E4Hyn2kD-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 11.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.4-dirty
# https://github.com/intel-lab-lkp/linux/commit/4b66a617bf6d095d33fe43e9dbcfdf2e0de9fb29
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Eric-W-Biederman/signal-alpha-Remove-unused-definition-of-TASK_REAL_PARENT/20220519-065947
git checkout 4b66a617bf6d095d33fe43e9dbcfdf2e0de9fb29
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=parisc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
kernel/signal.c: note: in included file (through arch/parisc/include/uapi/asm/signal.h, arch/parisc/include/asm/signal.h, include/uapi/linux/signal.h, ...):
include/uapi/asm-generic/signal-defs.h:83:29: sparse: sparse: multiple address spaces given
kernel/signal.c:195:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:195:31: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:195:31: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:198:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:198:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:198:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:480:9: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:480:9: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:480:9: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:484:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:484:34: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:484:34: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:542:53: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct k_sigaction *ka @@ got struct k_sigaction [noderef] __rcu * @@
kernel/signal.c:542:53: sparse: expected struct k_sigaction *ka
kernel/signal.c:542:53: sparse: got struct k_sigaction [noderef] __rcu *
include/uapi/asm-generic/signal-defs.h:83:29: sparse: sparse: multiple address spaces given
kernel/signal.c:1261:9: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: cannot dereference this type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: cannot dereference this type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: cannot dereference this type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: cannot dereference this type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: cannot dereference this type
kernel/signal.c:1267:29: sparse: sparse: no member 'ip' in struct pt_regs
kernel/signal.c:1267:29: sparse: sparse: cast from unknown type
kernel/signal.c:1267:29: sparse: sparse: incompatible types for 'case' statement
kernel/signal.c:1267:29: sparse: sparse: incompatible types for 'case' statement
kernel/signal.c:1267:29: sparse: sparse: incompatible types for 'case' statement
kernel/signal.c:1267:29: sparse: sparse: incompatible types for 'case' statement
kernel/signal.c:1328:9: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:1328:9: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:1328:9: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:1329:16: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct k_sigaction *action @@ got struct k_sigaction [noderef] __rcu * @@
kernel/signal.c:1329:16: sparse: expected struct k_sigaction *action
kernel/signal.c:1329:16: sparse: got struct k_sigaction [noderef] __rcu *
kernel/signal.c:1349:34: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:1349:34: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:1349:34: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:1938:36: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:1938:36: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:1938:36: sparse: got struct spinlock [noderef] __rcu *
>> kernel/signal.c:2048:46: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct sighand_struct *m_sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2048:46: sparse: expected struct sighand_struct *m_sighand
kernel/signal.c:2048:46: sparse: got struct sighand_struct [noderef] __rcu *sighand
kernel/signal.c:2057:24: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *parent @@ got struct task_struct [noderef] __rcu *real_parent @@
kernel/signal.c:2057:24: sparse: expected struct task_struct *parent
kernel/signal.c:2057:24: sparse: got struct task_struct [noderef] __rcu *real_parent
kernel/signal.c:2087:21: sparse: sparse: incompatible types in comparison expression (different address spaces):
>> kernel/signal.c:2087:21: sparse: struct task_struct [noderef] __rcu *
>> kernel/signal.c:2087:21: sparse: struct task_struct *
>> kernel/signal.c:2117:40: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct task_struct *parent @@ got struct task_struct [noderef] __rcu *real_parent @@
kernel/signal.c:2117:40: sparse: expected struct task_struct *parent
kernel/signal.c:2117:40: sparse: got struct task_struct [noderef] __rcu *real_parent
kernel/signal.c:2119:46: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct sighand_struct *m_sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2119:46: sparse: expected struct sighand_struct *m_sighand
kernel/signal.c:2119:46: sparse: got struct sighand_struct [noderef] __rcu *sighand
>> kernel/signal.c:2120:50: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct sighand_struct *p_sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2120:50: sparse: expected struct sighand_struct *p_sighand
kernel/signal.c:2120:50: sparse: got struct sighand_struct [noderef] __rcu *sighand
>> kernel/signal.c:2125:58: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct sighand_struct *t_sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2125:58: sparse: expected struct sighand_struct *t_sighand
kernel/signal.c:2125:58: sparse: got struct sighand_struct [noderef] __rcu *sighand
kernel/signal.c:2171:44: sparse: sparse: cast removes address space '__rcu' of expression
kernel/signal.c:2190:65: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct task_struct *tsk @@ got struct task_struct [noderef] __rcu *parent @@
kernel/signal.c:2190:65: sparse: expected struct task_struct *tsk
kernel/signal.c:2190:65: sparse: got struct task_struct [noderef] __rcu *parent
kernel/signal.c:2191:40: sparse: sparse: cast removes address space '__rcu' of expression
kernel/signal.c:2209:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct sighand_struct *psig @@ got struct sighand_struct [noderef] __rcu *[noderef] __rcu sighand @@
kernel/signal.c:2209:14: sparse: expected struct sighand_struct *psig
kernel/signal.c:2209:14: sparse: got struct sighand_struct [noderef] __rcu *[noderef] __rcu sighand
kernel/signal.c:2238:53: sparse: sparse: incorrect type in argument 3 (different address spaces) @@ expected struct task_struct *t @@ got struct task_struct [noderef] __rcu *parent @@
kernel/signal.c:2238:53: sparse: expected struct task_struct *t
kernel/signal.c:2238:53: sparse: got struct task_struct [noderef] __rcu *parent
kernel/signal.c:2239:34: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct task_struct *parent @@ got struct task_struct [noderef] __rcu *parent @@
kernel/signal.c:2239:34: sparse: expected struct task_struct *parent
kernel/signal.c:2239:34: sparse: got struct task_struct [noderef] __rcu *parent
kernel/signal.c:2269:24: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *parent @@ got struct task_struct [noderef] __rcu *parent @@
kernel/signal.c:2269:24: sparse: expected struct task_struct *parent
kernel/signal.c:2269:24: sparse: got struct task_struct [noderef] __rcu *parent
kernel/signal.c:2272:24: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct task_struct *parent @@ got struct task_struct [noderef] __rcu *real_parent @@
kernel/signal.c:2272:24: sparse: expected struct task_struct *parent
kernel/signal.c:2272:24: sparse: got struct task_struct [noderef] __rcu *real_parent
kernel/signal.c:2307:17: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct sighand_struct *sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2307:17: sparse: expected struct sighand_struct *sighand
kernel/signal.c:2307:17: sparse: got struct sighand_struct [noderef] __rcu *sighand
kernel/signal.c:2341:41: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2341:41: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2341:41: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2343:39: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2343:39: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2343:39: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2428:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2428:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2428:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2440:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2440:31: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2440:31: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2479:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2479:31: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2479:31: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2481:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2481:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2481:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2584:41: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2584:41: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2584:41: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2599:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2599:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2599:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2656:41: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2656:41: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2656:41: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2668:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:2668:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:2668:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:2726:49: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct sighand_struct *sighand @@ got struct sighand_struct [noderef] __rcu *sighand @@
kernel/signal.c:2726:49: sparse: expected struct sighand_struct *sighand
kernel/signal.c:2726:49: sparse: got struct sighand_struct [noderef] __rcu *sighand
kernel/signal.c:3052:27: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3052:27: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3052:27: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3081:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3081:29: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3081:29: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3138:27: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3138:27: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3138:27: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3140:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3140:29: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3140:29: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3291:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3291:31: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3291:31: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3294:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3294:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3294:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3683:27: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3683:27: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3683:27: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3695:37: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3695:37: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3695:37: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3700:35: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3700:35: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3700:35: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:3705:29: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:3705:29: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:3705:29: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:4159:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:4159:31: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:4159:31: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:4171:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:4171:33: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:4171:33: sparse: got struct spinlock [noderef] __rcu *
kernel/signal.c:4189:11: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct k_sigaction *k @@ got struct k_sigaction [noderef] __rcu * @@
kernel/signal.c:4189:11: sparse: expected struct k_sigaction *k
kernel/signal.c:4189:11: sparse: got struct k_sigaction [noderef] __rcu *
kernel/signal.c:4191:25: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct spinlock [usertype] *lock @@ got struct spinlock [noderef] __rcu * @@
kernel/signal.c:4191:25: sparse: expected struct spinlock [usertype] *lock
kernel/signal.c:4191:25: sparse: got struct spinlock [noderef] __rcu *
vim +2048 kernel/signal.c
1934
1935 void sigqueue_free(struct sigqueue *q)
1936 {
1937 unsigned long flags;
> 1938 spinlock_t *lock = ¤t->sighand->siglock;
1939
1940 BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
1941 /*
1942 * We must hold ->siglock while testing q->list
1943 * to serialize with collect_signal() or with
1944 * __exit_signal()->flush_sigqueue().
1945 */
1946 spin_lock_irqsave(lock, flags);
1947 q->flags &= ~SIGQUEUE_PREALLOC;
1948 /*
1949 * If it is queued it will be freed when dequeued,
1950 * like the "regular" sigqueue.
1951 */
1952 if (!list_empty(&q->list))
1953 q = NULL;
1954 spin_unlock_irqrestore(lock, flags);
1955
1956 if (q)
1957 __sigqueue_free(q);
1958 }
1959
1960 int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type)
1961 {
1962 int sig = q->info.si_signo;
1963 struct sigpending *pending;
1964 struct task_struct *t;
1965 unsigned long flags;
1966 int ret, result;
1967
1968 BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
1969
1970 ret = -1;
1971 rcu_read_lock();
1972 t = pid_task(pid, type);
1973 if (!t || !likely(lock_task_sighand(t, &flags)))
1974 goto ret;
1975
1976 ret = 1; /* the signal is ignored */
1977 result = TRACE_SIGNAL_IGNORED;
1978 if (!prepare_signal(sig, t, false))
1979 goto out;
1980
1981 ret = 0;
1982 if (unlikely(!list_empty(&q->list))) {
1983 /*
1984 * If an SI_TIMER entry is already queue just increment
1985 * the overrun count.
1986 */
1987 BUG_ON(q->info.si_code != SI_TIMER);
1988 q->info.si_overrun++;
1989 result = TRACE_SIGNAL_ALREADY_PENDING;
1990 goto out;
1991 }
1992 q->info.si_overrun = 0;
1993
1994 signalfd_notify(t, sig);
1995 pending = (type != PIDTYPE_PID) ? &t->signal->shared_pending : &t->pending;
1996 list_add_tail(&q->list, &pending->list);
1997 sigaddset(&pending->signal, sig);
1998 complete_signal(sig, t, type);
1999 result = TRACE_SIGNAL_DELIVERED;
2000 out:
2001 trace_signal_generate(sig, &q->info, t, type != PIDTYPE_PID, result);
2002 unlock_task_sighand(t, &flags);
2003 ret:
2004 rcu_read_unlock();
2005 return ret;
2006 }
2007
2008 /**
2009 * lock_parents_siglocks - Take current, real_parent, and parent's siglock
2010 * @lock_tracer: The tracers siglock is needed.
2011 *
2012 * There is no natural ordering to these locks so they must be sorted
2013 * before being taken.
2014 *
2015 * There are two complicating factors here:
2016 * - The locks live in sighand and sighand can be arbitrarily shared
2017 * - parent and real_parent can change when current's siglock is unlocked.
2018 *
2019 * To deal with this first the all of the sighand pointers are
2020 * gathered under current's siglock, and the sighand pointers are
2021 * sorted. As siglock lives inside of sighand this also sorts the
2022 * siglock's by address.
2023 *
2024 * Then the siglocks are taken in order dropping current's siglock if
2025 * necessary.
2026 *
2027 * Finally if parent and real_parent have not changed return.
2028 * If they either parent has changed drop their locks and try again.
2029 *
2030 * Changing sighand is an infrequent and somewhat expensive operation
2031 * (unshare or exec) and so even in the worst case this loop
2032 * should not loop too many times before all of the proper locks are
2033 * taken in order.
2034 *
2035 * CONTEXT:
2036 * Must be called with @current->sighand->siglock held
2037 *
2038 * RETURNS:
2039 * current's, real_parent's, and parent's siglock held.
2040 */
2041 static void lock_parents_siglocks(bool lock_tracer)
2042 __releases(¤t->sighand->siglock)
2043 __acquires(¤t->sighand->siglock)
2044 __acquires(¤t->real_parent->sighand->siglock)
2045 __acquires(¤t->parent->sighand->siglock)
2046 {
2047 struct task_struct *me = current;
> 2048 struct sighand_struct *m_sighand = me->sighand;
2049
2050 lockdep_assert_held(&m_sighand->siglock);
2051
2052 rcu_read_lock();
2053 for (;;) {
2054 struct task_struct *parent, *tracer;
2055 struct sighand_struct *p_sighand, *t_sighand, *s1, *s2, *s3;
2056
2057 parent = me->real_parent;
2058 tracer = ptrace_parent(me);
2059 if (!tracer || !lock_tracer)
2060 tracer = parent;
2061
2062 p_sighand = rcu_dereference(parent->sighand);
2063 t_sighand = rcu_dereference(tracer->sighand);
2064
2065 /* Sort the sighands so that s1 >= s2 >= s3 */
2066 s1 = m_sighand;
2067 s2 = p_sighand;
2068 s3 = t_sighand;
2069 if (s1 > s2)
2070 swap(s1, s2);
2071 if (s1 > s3)
2072 swap(s1, s3);
2073 if (s2 > s3)
2074 swap(s2, s3);
2075
2076 /* Take the locks in order */
2077 if (s1 != m_sighand) {
2078 spin_unlock(&m_sighand->siglock);
2079 spin_lock(&s1->siglock);
2080 }
2081 if (s1 != s2)
2082 spin_lock_nested(&s2->siglock, 1);
2083 if (s2 != s3)
2084 spin_lock_nested(&s3->siglock, 2);
2085
2086 /* Verify the proper locks are held */
> 2087 if (likely((s1 == m_sighand) ||
2088 ((me->real_parent == parent) &&
2089 (me->parent == tracer) &&
2090 (parent->sighand == p_sighand) &&
2091 (tracer->sighand == t_sighand)))) {
2092 break;
2093 }
2094
2095 /* Drop all but current's siglock */
2096 if (p_sighand != m_sighand)
2097 spin_unlock(&p_sighand->siglock);
2098 if (t_sighand != p_sighand)
2099 spin_unlock(&t_sighand->siglock);
2100
2101 /*
2102 * Since [pt]_sighand will likely change if we go
2103 * around, and m_sighand is the only one held, make sure
2104 * it is subclass-0, since the above 's1 != m_sighand'
2105 * clause very much relies on that.
2106 */
2107 lock_set_subclass(&m_sighand->siglock.dep_map, 0, _RET_IP_);
2108 }
2109 rcu_read_unlock();
2110 }
2111
2112 static void unlock_parents_siglocks(bool unlock_tracer)
2113 __releases(¤t->real_parent->sighand->siglock)
2114 __releases(¤t->parent->sighand->siglock)
2115 {
2116 struct task_struct *me = current;
> 2117 struct task_struct *parent = me->real_parent;
2118 struct task_struct *tracer = ptrace_parent(me);
2119 struct sighand_struct *m_sighand = me->sighand;
> 2120 struct sighand_struct *p_sighand = parent->sighand;
2121
2122 if (p_sighand != m_sighand)
2123 spin_unlock(&p_sighand->siglock);
2124 if (tracer && unlock_tracer) {
> 2125 struct sighand_struct *t_sighand = tracer->sighand;
2126 if (t_sighand != p_sighand)
2127 spin_unlock(&t_sighand->siglock);
2128 }
2129 }
2130
diff --git a/kernel/signal.c b/kernel/signal.c index 2cc45e8448e2..d4956be51939 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1994,6 +1994,129 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type) return ret; } +/** + * lock_parents_siglocks - Take current, real_parent, and parent's siglock + * @lock_tracer: The tracers siglock is needed. + * + * There is no natural ordering to these locks so they must be sorted + * before being taken. + * + * There are two complicating factors here: + * - The locks live in sighand and sighand can be arbitrarily shared + * - parent and real_parent can change when current's siglock is unlocked. + * + * To deal with this first the all of the sighand pointers are + * gathered under current's siglock, and the sighand pointers are + * sorted. As siglock lives inside of sighand this also sorts the + * siglock's by address. + * + * Then the siglocks are taken in order dropping current's siglock if + * necessary. + * + * Finally if parent and real_parent have not changed return. + * If they either parent has changed drop their locks and try again. + * + * Changing sighand is an infrequent and somewhat expensive operation + * (unshare or exec) and so even in the worst case this loop + * should not loop too many times before all of the proper locks are + * taken in order. + * + * CONTEXT: + * Must be called with @current->sighand->siglock held + * + * RETURNS: + * current's, real_parent's, and parent's siglock held. + */ +static void lock_parents_siglocks(bool lock_tracer) + __releases(¤t->sighand->siglock) + __acquires(¤t->sighand->siglock) + __acquires(¤t->real_parent->sighand->siglock) + __acquires(¤t->parent->sighand->siglock) +{ + struct task_struct *me = current; + struct sighand_struct *m_sighand = me->sighand; + + lockdep_assert_held(&m_sighand->siglock); + + rcu_read_lock(); + for (;;) { + struct task_struct *parent, *tracer; + struct sighand_struct *p_sighand, *t_sighand, *s1, *s2, *s3; + + parent = me->real_parent; + tracer = ptrace_parent(me); + if (!tracer || !lock_tracer) + tracer = parent; + + p_sighand = rcu_dereference(parent->sighand); + t_sighand = rcu_dereference(tracer->sighand); + + /* Sort the sighands so that s1 >= s2 >= s3 */ + s1 = m_sighand; + s2 = p_sighand; + s3 = t_sighand; + if (s1 > s2) + swap(s1, s2); + if (s1 > s3) + swap(s1, s3); + if (s2 > s3) + swap(s2, s3); + + /* Take the locks in order */ + if (s1 != m_sighand) { + spin_unlock(&m_sighand->siglock); + spin_lock(&s1->siglock); + } + if (s1 != s2) + spin_lock_nested(&s2->siglock, 1); + if (s2 != s3) + spin_lock_nested(&s3->siglock, 2); + + /* Verify the proper locks are held */ + if (likely((s1 == m_sighand) || + ((me->real_parent == parent) && + (me->parent == tracer) && + (parent->sighand == p_sighand) && + (tracer->sighand == t_sighand)))) { + break; + } + + /* Drop all but current's siglock */ + if (p_sighand != m_sighand) + spin_unlock(&p_sighand->siglock); + if (t_sighand != p_sighand) + spin_unlock(&t_sighand->siglock); + + /* + * Since [pt]_sighand will likely change if we go + * around, and m_sighand is the only one held, make sure + * it is subclass-0, since the above 's1 != m_sighand' + * clause very much relies on that. + */ + lock_set_subclass(&m_sighand->siglock.dep_map, 0, _RET_IP_); + } + rcu_read_unlock(); +} + +static void unlock_parents_siglocks(bool unlock_tracer) + __releases(¤t->real_parent->sighand->siglock) + __releases(¤t->parent->sighand->siglock) +{ + struct task_struct *me = current; + struct task_struct *parent = me->real_parent; + struct task_struct *tracer = ptrace_parent(me); + struct sighand_struct *m_sighand = me->sighand; + struct sighand_struct *p_sighand = parent->sighand; + + if (p_sighand != m_sighand) + spin_unlock(&p_sighand->siglock); + if (tracer && unlock_tracer) { + struct sighand_struct *t_sighand = tracer->sighand; + if (t_sighand != p_sighand) + spin_unlock(&t_sighand->siglock); + } +} + static void do_notify_pidfd(struct task_struct *task) { struct pid *pid; @@ -2125,11 +2248,12 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, bool for_ptracer, int why) { struct kernel_siginfo info; - unsigned long flags; struct task_struct *parent; struct sighand_struct *sighand; u64 utime, stime; + lockdep_assert_held(&tsk->sighand->siglock); + if (for_ptracer) { parent = tsk->parent; } else { @@ -2137,6 +2261,8 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, parent = tsk->real_parent; } + lockdep_assert_held(&parent->sighand->siglock); + clear_siginfo(&info); info.si_signo = SIGCHLD; info.si_errno = 0; @@ -2168,7 +2294,6 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, } sighand = parent->sighand; - spin_lock_irqsave(&sighand->siglock, flags); if (sighand->action[SIGCHLD-1].sa.sa_handler != SIG_IGN && !(sighand->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP)) send_signal_locked(SIGCHLD, &info, parent, PIDTYPE_TGID); @@ -2176,7 +2301,6 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, * Even if SIGCHLD is not generated, we must wake up wait4 calls. */ __wake_up_parent(tsk, parent); - spin_unlock_irqrestore(&sighand->siglock, flags); } /* @@ -2208,14 +2332,18 @@ static void ptrace_stop(int exit_code, int why, unsigned long message, spin_lock_irq(¤t->sighand->siglock); } + lock_parents_siglocks(true); /* * After this point ptrace_signal_wake_up or signal_wake_up * will clear TASK_TRACED if ptrace_unlink happens or a fatal * signal comes in. Handle previous ptrace_unlinks and fatal * signals here to prevent ptrace_stop sleeping in schedule. */ - if (!current->ptrace || __fatal_signal_pending(current)) + + if (!current->ptrace || __fatal_signal_pending(current)) { + unlock_parents_siglocks(true); return; + } set_special_state(TASK_TRACED); current->jobctl |= JOBCTL_TRACED; @@ -2254,16 +2382,6 @@ static void ptrace_stop(int exit_code, int why, unsigned long message, if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING)) gstop_done = task_participate_group_stop(current); - /* any trap clears pending STOP trap, STOP trap clears NOTIFY */ - task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); - if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) - task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); - - /* entering a trap, clear TRAPPING */ - task_clear_jobctl_trapping(current); - - spin_unlock_irq(¤t->sighand->siglock); - read_lock(&tasklist_lock); /* * Notify parents of the stop. * @@ -2279,14 +2397,25 @@ static void ptrace_stop(int exit_code, int why, unsigned long message, if (gstop_done && (!current->ptrace || ptrace_reparented(current))) do_notify_parent_cldstop(current, false, why); + unlock_parents_siglocks(true); + + /* any trap clears pending STOP trap, STOP trap clears NOTIFY */ + task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP); + if (info && info->si_code >> 8 == PTRACE_EVENT_STOP) + task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY); + + /* entering a trap, clear TRAPPING */ + task_clear_jobctl_trapping(current); + /* * Don't want to allow preemption here, because * sys_ptrace() needs this task to be inactive. * - * XXX: implement read_unlock_no_resched(). + * XXX: implement spin_unlock_no_resched(). */ preempt_disable(); - read_unlock(&tasklist_lock); + spin_unlock_irq(¤t->sighand->siglock); + cgroup_enter_frozen(); preempt_enable_no_resched(); freezable_schedule(); @@ -2361,8 +2490,8 @@ int ptrace_notify(int exit_code, unsigned long message) * on %true return. * * RETURNS: - * %false if group stop is already cancelled or ptrace trap is scheduled. - * %true if participated in group stop. + * %false if group stop is already cancelled. + * %true otherwise (as lock_parents_siglocks may have dropped siglock). */ static bool do_signal_stop(int signr) __releases(¤t->sighand->siglock) @@ -2425,36 +2554,24 @@ static bool do_signal_stop(int signr) } } + lock_parents_siglocks(false); + /* Recheck JOBCTL_STOP_PENDING after unlock+lock of siglock */ + if (unlikely(!(current->jobctl & JOBCTL_STOP_PENDING))) + goto out; if (likely(!current->ptrace)) { - int notify = 0; - /* * If there are no other threads in the group, or if there * is a group stop in progress and we are the last to stop, - * report to the parent. + * report to the real_parent. */ if (task_participate_group_stop(current)) - notify = CLD_STOPPED; + do_notify_parent_cldstop(current, false, CLD_STOPPED); + unlock_parents_siglocks(false); current->jobctl |= JOBCTL_STOPPED; set_special_state(TASK_STOPPED); spin_unlock_irq(¤t->sighand->siglock); - /* - * Notify the parent of the group stop completion. Because - * we're not holding either the siglock or tasklist_lock - * here, ptracer may attach inbetween; however, this is for - * group stop and should always be delivered to the real - * parent of the group leader. The new ptracer will get - * its notification when this task transitions into - * TASK_TRACED. - */ - if (notify) { - read_lock(&tasklist_lock); - do_notify_parent_cldstop(current, false, notify); - read_unlock(&tasklist_lock); - } - /* Now we don't run again until woken by SIGCONT or SIGKILL */ cgroup_enter_frozen(); freezable_schedule(); @@ -2465,8 +2582,11 @@ static bool do_signal_stop(int signr) * Schedule it and let the caller deal with it. */ task_set_jobctl_pending(current, JOBCTL_TRAP_STOP); - return false; } +out: + unlock_parents_siglocks(false); + spin_unlock_irq(¤t->sighand->siglock); + return true; } /** @@ -2624,32 +2744,30 @@ bool get_signal(struct ksignal *ksig) if (unlikely(signal->flags & SIGNAL_CLD_MASK)) { int why; - if (signal->flags & SIGNAL_CLD_CONTINUED) - why = CLD_CONTINUED; - else - why = CLD_STOPPED; + lock_parents_siglocks(true); + /* Recheck signal->flags after unlock+lock of siglock */ + if (likely(signal->flags & SIGNAL_CLD_MASK)) { + if (signal->flags & SIGNAL_CLD_CONTINUED) + why = CLD_CONTINUED; + else + why = CLD_STOPPED; - signal->flags &= ~SIGNAL_CLD_MASK; + signal->flags &= ~SIGNAL_CLD_MASK; - spin_unlock_irq(&sighand->siglock); - - /* - * Notify the parent that we're continuing. This event is - * always per-process and doesn't make whole lot of sense - * for ptracers, who shouldn't consume the state via - * wait(2) either, but, for backward compatibility, notify - * the ptracer of the group leader too unless it's gonna be - * a duplicate. - */ - read_lock(&tasklist_lock); - do_notify_parent_cldstop(current, false, why); - - if (ptrace_reparented(current->group_leader)) - do_notify_parent_cldstop(current->group_leader, - true, why); - read_unlock(&tasklist_lock); - - goto relock; + /* + * Notify the parent that we're continuing. This event is + * always per-process and doesn't make whole lot of sense + * for ptracers, who shouldn't consume the state via + * wait(2) either, but, for backward compatibility, notify + * the ptracer of the group leader too unless it's gonna be + * a duplicate. + */ + do_notify_parent_cldstop(current, false, why); + if (ptrace_reparented(current->group_leader)) + do_notify_parent_cldstop(current->group_leader, + true, why); + } + unlock_parents_siglocks(true); } for (;;) { @@ -2906,7 +3024,6 @@ static void retarget_shared_pending(struct task_struct *tsk, sigset_t *which) void exit_signals(struct task_struct *tsk) { - int group_stop = 0; sigset_t unblocked; /* @@ -2937,21 +3054,20 @@ void exit_signals(struct task_struct *tsk) signotset(&unblocked); retarget_shared_pending(tsk, &unblocked); - if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) && - task_participate_group_stop(tsk)) - group_stop = CLD_STOPPED; -out: - spin_unlock_irq(&tsk->sighand->siglock); - /* * If group stop has completed, deliver the notification. This * should always go to the real parent of the group leader. */ - if (unlikely(group_stop)) { - read_lock(&tasklist_lock); - do_notify_parent_cldstop(tsk, false, group_stop); - read_unlock(&tasklist_lock); + if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING)) { + lock_parents_siglocks(false); + /* Recheck JOBCTL_STOP_PENDING after unlock+lock of siglock */ + if ((tsk->jobctl & JOBCTL_STOP_PENDING) && + task_participate_group_stop(tsk)) + do_notify_parent_cldstop(tsk, false, CLD_STOPPED); + unlock_parents_siglocks(false); } +out: + spin_unlock_irq(&tsk->sighand->siglock); } /*
Now that siglock keeps tsk->parent and tsk->real_parent constant require that do_notify_parent_cldstop is called with tsk->siglock held instead of the tasklist_lock. As all of the callers of do_notify_parent_cldstop had to drop the siglock and take tasklist_lock this simplifies all of it's callers. This removes one reason for taking tasklist_lock. This makes ptrace_stop so that it should reliably work correctly and reliably with PREEMPT_RT enabled and CONFIG_CGROUPS disabled. The remaining challenge is that cgroup_enter_frozen takes spin_lock after __state has been set to TASK_TRACED. Which on PREEMPT_RT means the code can sleep and change __state. Not only that but it means that wait_task_inactive could potentially detect the code scheduling away at that point and fail, causing ptrace_check_attach to fail. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> --- kernel/signal.c | 262 ++++++++++++++++++++++++++++++++++-------------- 1 file changed, 189 insertions(+), 73 deletions(-)