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-...@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 <l...@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 -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um
