diff options
Diffstat (limited to 'target/linux/generic/patches-2.6.31/965-arm_restore_sigmask_v2.patch')
| -rw-r--r-- | target/linux/generic/patches-2.6.31/965-arm_restore_sigmask_v2.patch | 354 |
1 files changed, 0 insertions, 354 deletions
diff --git a/target/linux/generic/patches-2.6.31/965-arm_restore_sigmask_v2.patch b/target/linux/generic/patches-2.6.31/965-arm_restore_sigmask_v2.patch deleted file mode 100644 index 61feb7d797..0000000000 --- a/target/linux/generic/patches-2.6.31/965-arm_restore_sigmask_v2.patch +++ /dev/null @@ -1,354 +0,0 @@ -From: Mikael Pettersson <mikpe@it.uu.se> -Date: Sat, 15 Aug 2009 11:58:11 +0000 (+0100) -Subject: ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwait -X-Git-Tag: next-20090817~86^2~1^6 -X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Fnext%2Flinux-next.git;a=commitdiff_plain;h=369842658a36bcea28ecb643ba4bdb53919330dd - -ARM: 5677/1: ARM support for TIF_RESTORE_SIGMASK/pselect6/ppoll/epoll_pwait - -This patch adds support for TIF_RESTORE_SIGMASK to ARM's -signal handling, which allows to hook up the pselect6, ppoll, -and epoll_pwait syscalls on ARM. - -Tested here with eabi userspace and a test program with a -deliberate race between a child's exit and the parent's -sigprocmask/select sequence. Using sys_pselect6() instead -of sigprocmask/select reliably prevents the race. - -The other arch's support for TIF_RESTORE_SIGMASK has evolved -over time: - -In 2.6.16: -- add TIF_RESTORE_SIGMASK which parallels TIF_SIGPENDING -- test both when checking for pending signal [changed later] -- reimplement sys_sigsuspend() to use current->saved_sigmask, - TIF_RESTORE_SIGMASK [changed later], and -ERESTARTNOHAND; - ditto for sys_rt_sigsuspend(), but drop private code and - use common code via __ARCH_WANT_SYS_RT_SIGSUSPEND; -- there are now no "extra" calls to do_signal() so its oldset - parameter is always ¤t->blocked so need not be passed, - also its return value is changed to void -- change handle_signal() to return 0/-errno -- change do_signal() to honor TIF_RESTORE_SIGMASK: - + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK - is set - + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK - + if no signal was delivered and TIF_RESTORE_SIGMASK is set then - clear it and restore the sigmask -- hook up sys_pselect6() and sys_ppoll() - -In 2.6.19: -- hook up sys_epoll_pwait() - -In 2.6.26: -- allow archs to override how TIF_RESTORE_SIGMASK is implemented; - default set_restore_sigmask() sets both TIF_RESTORE_SIGMASK and - TIF_SIGPENDING; archs need now just test TIF_SIGPENDING again - when checking for pending signal work; some archs now implement - TIF_RESTORE_SIGMASK as a secondary/non-atomic thread flag bit -- call set_restore_sigmask() in sys_sigsuspend() instead of setting - TIF_RESTORE_SIGMASK - -In 2.6.29-rc: -- kill sys_pselect7() which no arch wanted - -So for 2.6.31-rc6/ARM this patch does the following: -- Add TIF_RESTORE_SIGMASK. Use the generic set_restore_sigmask() - which sets both TIF_SIGPENDING and TIF_RESTORE_SIGMASK, so - TIF_RESTORE_SIGMASK need not claim one of the scarce low thread - flags, and existing TIF_SIGPENDING and _TIF_WORK_MASK tests need - not be extended for TIF_RESTORE_SIGMASK. -- sys_sigsuspend() is reimplemented to use current->saved_sigmask - and set_restore_sigmask(), making it identical to most other archs -- The private code for sys_rt_sigsuspend() is removed, instead - generic code supplies it via __ARCH_WANT_SYS_RT_SIGSUSPEND. -- sys_sigsuspend() and sys_rt_sigsuspend() no longer need a pt_regs - parameter, so their assembly code wrappers are removed. -- handle_signal() is changed to return 0 on success or -errno. -- The oldset parameter to do_signal() is now redundant and removed, - and the return value is now also redundant and changed to void. -- do_signal() is changed to honor TIF_RESTORE_SIGMASK: - + get oldset from current->saved_sigmask if TIF_RESTORE_SIGMASK - is set - + if handle_signal() was successful then clear TIF_RESTORE_SIGMASK - + if no signal was delivered and TIF_RESTORE_SIGMASK is set then - clear it and restore the sigmask -- Hook up sys_pselect6, sys_ppoll, and sys_epoll_pwait. - -Signed-off-by: Mikael Pettersson <mikpe@it.uu.se> -Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> ---- - ---- a/arch/arm/include/asm/thread_info.h -+++ b/arch/arm/include/asm/thread_info.h -@@ -140,6 +140,7 @@ extern void vfp_sync_state(struct thread - #define TIF_USING_IWMMXT 17 - #define TIF_MEMDIE 18 - #define TIF_FREEZE 19 -+#define TIF_RESTORE_SIGMASK 20 - - #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) - #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) -@@ -147,6 +148,7 @@ extern void vfp_sync_state(struct thread - #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) - #define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT) - #define _TIF_FREEZE (1 << TIF_FREEZE) -+#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) - - /* - * Change these and you break ASM code in entry-common.S ---- a/arch/arm/include/asm/unistd.h -+++ b/arch/arm/include/asm/unistd.h -@@ -360,8 +360,8 @@ - #define __NR_readlinkat (__NR_SYSCALL_BASE+332) - #define __NR_fchmodat (__NR_SYSCALL_BASE+333) - #define __NR_faccessat (__NR_SYSCALL_BASE+334) -- /* 335 for pselect6 */ -- /* 336 for ppoll */ -+#define __NR_pselect6 (__NR_SYSCALL_BASE+335) -+#define __NR_ppoll (__NR_SYSCALL_BASE+336) - #define __NR_unshare (__NR_SYSCALL_BASE+337) - #define __NR_set_robust_list (__NR_SYSCALL_BASE+338) - #define __NR_get_robust_list (__NR_SYSCALL_BASE+339) -@@ -372,7 +372,7 @@ - #define __NR_vmsplice (__NR_SYSCALL_BASE+343) - #define __NR_move_pages (__NR_SYSCALL_BASE+344) - #define __NR_getcpu (__NR_SYSCALL_BASE+345) -- /* 346 for epoll_pwait */ -+#define __NR_epoll_pwait (__NR_SYSCALL_BASE+346) - #define __NR_kexec_load (__NR_SYSCALL_BASE+347) - #define __NR_utimensat (__NR_SYSCALL_BASE+348) - #define __NR_signalfd (__NR_SYSCALL_BASE+349) -@@ -432,6 +432,7 @@ - #define __ARCH_WANT_SYS_SIGPENDING - #define __ARCH_WANT_SYS_SIGPROCMASK - #define __ARCH_WANT_SYS_RT_SIGACTION -+#define __ARCH_WANT_SYS_RT_SIGSUSPEND - - #if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT) - #define __ARCH_WANT_SYS_TIME ---- a/arch/arm/kernel/calls.S -+++ b/arch/arm/kernel/calls.S -@@ -81,7 +81,7 @@ - CALL(sys_ni_syscall) /* was sys_ssetmask */ - /* 70 */ CALL(sys_setreuid16) - CALL(sys_setregid16) -- CALL(sys_sigsuspend_wrapper) -+ CALL(sys_sigsuspend) - CALL(sys_sigpending) - CALL(sys_sethostname) - /* 75 */ CALL(sys_setrlimit) -@@ -188,7 +188,7 @@ - CALL(sys_rt_sigpending) - CALL(sys_rt_sigtimedwait) - CALL(sys_rt_sigqueueinfo) -- CALL(sys_rt_sigsuspend_wrapper) -+ CALL(sys_rt_sigsuspend) - /* 180 */ CALL(ABI(sys_pread64, sys_oabi_pread64)) - CALL(ABI(sys_pwrite64, sys_oabi_pwrite64)) - CALL(sys_chown16) -@@ -344,8 +344,8 @@ - CALL(sys_readlinkat) - CALL(sys_fchmodat) - CALL(sys_faccessat) --/* 335 */ CALL(sys_ni_syscall) /* eventually pselect6 */ -- CALL(sys_ni_syscall) /* eventually ppoll */ -+/* 335 */ CALL(sys_pselect6) -+ CALL(sys_ppoll) - CALL(sys_unshare) - CALL(sys_set_robust_list) - CALL(sys_get_robust_list) -@@ -355,7 +355,7 @@ - CALL(sys_vmsplice) - CALL(sys_move_pages) - /* 345 */ CALL(sys_getcpu) -- CALL(sys_ni_syscall) /* eventually epoll_pwait */ -+ CALL(sys_epoll_pwait) - CALL(sys_kexec_load) - CALL(sys_utimensat) - CALL(sys_signalfd) ---- a/arch/arm/kernel/entry-common.S -+++ b/arch/arm/kernel/entry-common.S -@@ -373,16 +373,6 @@ sys_clone_wrapper: - b sys_clone - ENDPROC(sys_clone_wrapper) - --sys_sigsuspend_wrapper: -- add r3, sp, #S_OFF -- b sys_sigsuspend --ENDPROC(sys_sigsuspend_wrapper) -- --sys_rt_sigsuspend_wrapper: -- add r2, sp, #S_OFF -- b sys_rt_sigsuspend --ENDPROC(sys_rt_sigsuspend_wrapper) -- - sys_sigreturn_wrapper: - add r0, sp, #S_OFF - b sys_sigreturn ---- a/arch/arm/kernel/signal.c -+++ b/arch/arm/kernel/signal.c -@@ -47,57 +47,22 @@ const unsigned long sigreturn_codes[7] = - MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, - }; - --static int do_signal(sigset_t *oldset, struct pt_regs * regs, int syscall); -- - /* - * atomically swap in the new signal mask, and wait for a signal. - */ --asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask, struct pt_regs *regs) -+asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask) - { -- sigset_t saveset; -- - mask &= _BLOCKABLE; - spin_lock_irq(¤t->sighand->siglock); -- saveset = current->blocked; -+ current->saved_sigmask = current->blocked; - siginitset(¤t->blocked, mask); - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); -- regs->ARM_r0 = -EINTR; -- -- while (1) { -- current->state = TASK_INTERRUPTIBLE; -- schedule(); -- if (do_signal(&saveset, regs, 0)) -- return regs->ARM_r0; -- } --} -- --asmlinkage int --sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize, struct pt_regs *regs) --{ -- sigset_t saveset, newset; -- -- /* XXX: Don't preclude handling different sized sigset_t's. */ -- if (sigsetsize != sizeof(sigset_t)) -- return -EINVAL; -- -- if (copy_from_user(&newset, unewset, sizeof(newset))) -- return -EFAULT; -- sigdelsetmask(&newset, ~_BLOCKABLE); -- -- spin_lock_irq(¤t->sighand->siglock); -- saveset = current->blocked; -- current->blocked = newset; -- recalc_sigpending(); -- spin_unlock_irq(¤t->sighand->siglock); -- regs->ARM_r0 = -EINTR; - -- while (1) { -- current->state = TASK_INTERRUPTIBLE; -- schedule(); -- if (do_signal(&saveset, regs, 0)) -- return regs->ARM_r0; -- } -+ current->state = TASK_INTERRUPTIBLE; -+ schedule(); -+ set_restore_sigmask(); -+ return -ERESTARTNOHAND; - } - - asmlinkage int -@@ -545,7 +510,7 @@ static inline void setup_syscall_restart - /* - * OK, we're invoking a handler - */ --static void -+static int - handle_signal(unsigned long sig, struct k_sigaction *ka, - siginfo_t *info, sigset_t *oldset, - struct pt_regs * regs, int syscall) -@@ -596,7 +561,7 @@ handle_signal(unsigned long sig, struct - - if (ret != 0) { - force_sigsegv(sig, tsk); -- return; -+ return ret; - } - - /* -@@ -610,6 +575,7 @@ handle_signal(unsigned long sig, struct - recalc_sigpending(); - spin_unlock_irq(&tsk->sighand->siglock); - -+ return 0; - } - - /* -@@ -621,11 +587,12 @@ handle_signal(unsigned long sig, struct - * the kernel can handle, and then we build all the user-level signal handling - * stack-frames in one go after that. - */ --static int do_signal(sigset_t *oldset, struct pt_regs *regs, int syscall) -+static void do_signal(struct pt_regs *regs, int syscall) - { - struct k_sigaction ka; - siginfo_t info; - int signr; -+ sigset_t *oldset; - - /* - * We want the common case to go fast, which -@@ -634,18 +601,32 @@ static int do_signal(sigset_t *oldset, s - * if so. - */ - if (!user_mode(regs)) -- return 0; -+ return; - - if (try_to_freeze()) - goto no_signal; - - single_step_clear(current); - -+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) -+ oldset = ¤t->saved_sigmask; -+ else -+ oldset = ¤t->blocked; -+ - signr = get_signal_to_deliver(&info, &ka, regs, NULL); - if (signr > 0) { -- handle_signal(signr, &ka, &info, oldset, regs, syscall); -+ if (handle_signal(signr, &ka, &info, oldset, regs, syscall) == 0) { -+ /* -+ * A signal was successfully delivered; the saved -+ * sigmask will have been stored in the signal frame, -+ * and will be restored by sigreturn, so we can simply -+ * clear the TIF_RESTORE_SIGMASK flag. -+ */ -+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) -+ clear_thread_flag(TIF_RESTORE_SIGMASK); -+ } - single_step_set(current); -- return 1; -+ return; - } - - no_signal: -@@ -697,14 +678,21 @@ static int do_signal(sigset_t *oldset, s - regs->ARM_r0 == -ERESTARTNOINTR) { - setup_syscall_restart(regs); - } -+ -+ /* If there's no signal to deliver, we just put the saved sigmask -+ * back. -+ */ -+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) { -+ clear_thread_flag(TIF_RESTORE_SIGMASK); -+ sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); -+ } - } - single_step_set(current); -- return 0; - } - - asmlinkage void - do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) - { - if (thread_flags & _TIF_SIGPENDING) -- do_signal(¤t->blocked, regs, syscall); -+ do_signal(regs, syscall); - } |