From 3af8588c77186bf08e55e7281da83d88373481d7 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Mon, 8 Jun 2020 17:28:50 +0200 Subject: fork: fold legacy_clone_args_valid() into _do_fork() This separate helper only existed to guarantee the mutual exclusivity of CLONE_PIDFD and CLONE_PARENT_SETTID for legacy clone since CLONE_PIDFD abuses the parent_tid field to return the pidfd. But we can actually handle this uniformely thus removing the helper. For legacy clone we can detect that CLONE_PIDFD is specified in conjunction with CLONE_PARENT_SETTID because they will share the same memory which is invalid and for clone3() setting the separate pidfd and parent_tid fields to the same memory is bogus as well. So fold that helper directly into _do_fork() by detecting this case. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Al Viro Cc: Geert Uytterhoeven Cc: "Matthew Wilcox (Oracle)" Cc: "Peter Zijlstra (Intel)" Cc: linux-m68k@lists.linux-m68k.org Cc: x86@kernel.org Signed-off-by: Christian Brauner --- include/linux/sched/task.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 38359071236a..ddce0ea515d1 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -96,7 +96,6 @@ extern void exit_files(struct task_struct *); extern void exit_itimers(struct signal_struct *); extern long _do_fork(struct kernel_clone_args *kargs); -extern bool legacy_clone_args_valid(const struct kernel_clone_args *kargs); extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); struct task_struct *fork_idle(int); struct mm_struct *copy_init_mm(void); -- cgit v1.2.3 From ff2a91127b374c75ae024b31d22f23ad49d16eb4 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Sun, 24 May 2020 20:57:00 +0200 Subject: fork: remove do_fork() Now that all architectures have been switched to use _do_fork() and the new struct kernel_clone_args calling convention we can remove the legacy do_fork() helper completely. The calling convention used to be brittle and do_fork() didn't buy us anything. The only calling convention accepted should be based on struct kernel_clone_args going forward. It's cleaner and uniform. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Al Viro Cc: "Matthew Wilcox (Oracle)" Cc: "Peter Zijlstra (Intel)" Signed-off-by: Christian Brauner --- include/linux/sched/task.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index ddce0ea515d1..9f03c44941fb 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -96,7 +96,6 @@ extern void exit_files(struct task_struct *); extern void exit_itimers(struct signal_struct *); extern long _do_fork(struct kernel_clone_args *kargs); -extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *); struct task_struct *fork_idle(int); struct mm_struct *copy_init_mm(void); extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); -- cgit v1.2.3 From 140c8180eb7c7cbda399f64474788b86db72db32 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Sun, 24 May 2020 23:34:20 +0200 Subject: arch: remove HAVE_COPY_THREAD_TLS All architectures support copy_thread_tls() now, so remove the legacy copy_thread() function and the HAVE_COPY_THREAD_TLS config option. Everyone uses the same process creation calling convention based on copy_thread_tls() and struct kernel_clone_args. This will make it easier to maintain the core process creation code under kernel/, simplifies the callpaths and makes the identical for all architectures. Cc: linux-arch@vger.kernel.org Acked-by: Thomas Bogendoerfer Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven Reviewed-by: Kees Cook Signed-off-by: Christian Brauner --- include/linux/sched/task.h | 15 +-------------- 1 file changed, 1 insertion(+), 14 deletions(-) (limited to 'include/linux') diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 9f03c44941fb..77cbe14c3034 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -65,22 +65,9 @@ extern void fork_init(void); extern void release_task(struct task_struct * p); -#ifdef CONFIG_HAVE_COPY_THREAD_TLS extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, struct task_struct *, unsigned long); -#else -extern int copy_thread(unsigned long, unsigned long, unsigned long, - struct task_struct *); - -/* Architectures that haven't opted into copy_thread_tls get the tls argument - * via pt_regs, so ignore the tls argument passed via C. */ -static inline int copy_thread_tls( - unsigned long clone_flags, unsigned long sp, unsigned long arg, - struct task_struct *p, unsigned long tls) -{ - return copy_thread(clone_flags, sp, arg, p); -} -#endif + extern void flush_thread(void); #ifdef CONFIG_HAVE_EXIT_THREAD -- cgit v1.2.3 From 714acdbd1c94e7e3ab90f6b6938f1ccb27b662f0 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Thu, 11 Jun 2020 11:04:15 +0200 Subject: arch: rename copy_thread_tls() back to copy_thread() Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls() back simply copy_thread(). It's a simpler name, and doesn't imply that only tls is copied here. This finishes an outstanding chunk of internal process creation work since we've added clone3(). Cc: linux-arch@vger.kernel.org Acked-by: Thomas Bogendoerfer A Acked-by: Stafford Horne Acked-by: Greentime Hu Acked-by: Geert Uytterhoeven A Reviewed-by: Kees Cook Signed-off-by: Christian Brauner --- include/linux/sched/task.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 77cbe14c3034..b6253f2ea96a 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -65,8 +65,8 @@ extern void fork_init(void); extern void release_task(struct task_struct * p); -extern int copy_thread_tls(unsigned long, unsigned long, unsigned long, - struct task_struct *, unsigned long); +extern int copy_thread(unsigned long, unsigned long, unsigned long, + struct task_struct *, unsigned long); extern void flush_thread(void); -- cgit v1.2.3