diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 9bd4ddd12b25c542ae9fad6fae963f66414b496c..5b248763a672414e925f217216fc21c9a2a257fb 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -322,6 +322,8 @@ static int drbd_thread_setup(void *arg) thi->name[0], resource->name); + allow_kernel_signal(DRBD_SIGKILL); + allow_kernel_signal(SIGXCPU); restart: retval = thi->function(thi); diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index a15a6e738eb5321dcde574c848f9a6435ffcd9aa..1795e80cbdf7b246c12f4bbdf758b14a1999d96a 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1113,7 +1113,7 @@ cifs_demultiplex_thread(void *p) mempool_resize(cifs_req_poolp, length + cifs_min_rcv); set_freezable(); - allow_signal(SIGKILL); + allow_kernel_signal(SIGKILL); while (server->tcpStatus != CifsExiting) { if (try_to_freeze()) continue; diff --git a/include/linux/signal.h b/include/linux/signal.h index b5d99482d3fe18e5f9c2eceb606a75458ae7e969..1a5f88316b081463a4e76bb8b48aa312f75162d5 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -282,6 +282,9 @@ extern void signal_setup_done(int failed, struct ksignal *ksig, int stepping); extern void exit_signals(struct task_struct *tsk); extern void kernel_sigaction(int, __sighandler_t); +#define SIG_KTHREAD ((__force __sighandler_t)2) +#define SIG_KTHREAD_KERNEL ((__force __sighandler_t)3) + static inline void allow_signal(int sig) { /* @@ -289,7 +292,17 @@ static inline void allow_signal(int sig) * know it'll be handled, so that they don't get converted to * SIGKILL or just silently dropped. */ - kernel_sigaction(sig, (__force __sighandler_t)2); + kernel_sigaction(sig, SIG_KTHREAD); +} + +static inline void allow_kernel_signal(int sig) +{ + /* + * Kernel threads handle their own signals. Let the signal code + * know signals sent by the kernel will be handled, so that they + * don't get silently dropped. + */ + kernel_sigaction(sig, SIG_KTHREAD_KERNEL); } static inline void disallow_signal(int sig) diff --git a/kernel/signal.c b/kernel/signal.c index e667be6907d71333c44546cd43ebfdde6c9eab3c..534fec266a334b299846034e878c271619fe5c71 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -90,6 +90,11 @@ static bool sig_task_ignored(struct task_struct *t, int sig, bool force) handler == SIG_DFL && !(force && sig_kernel_only(sig))) return true; + /* Only allow kernel generated signals to this kthread */ + if (unlikely((t->flags & PF_KTHREAD) && + (handler == SIG_KTHREAD_KERNEL) && !force)) + return true; + return sig_handler_ignored(handler, sig); }