leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[PATCH] Add TIF_RESTORE_SIGMASK

Browse Source 
We need TIF_RESTORE_SIGMASK in order to support ppoll() and pselect()
system calls. This patch originally came from Andi, and was based
heavily on David Howells' implementation of same on i386. I fixed a typo
which was causing do_signal() to use the wrong signal mask.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andi Kleen <ak@suse.de>
This commit is contained in:
Andi Kleen 2006-09-26 10:52:26 +02:00 committed by Andi Kleen
parent 3adbbcce9a
commit 1d001df19d
5 changed files with 49 additions and 68 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
arch/x86_64/ia32/ia32_signal.c
View File

@ -113,25 +113,19 @@ int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
}
asmlinkage long
sys32_sigsuspend(int history0, int history1, old_sigset_t mask,
struct pt_regs *regs)
sys32_sigsuspend(int history0, int history1, old_sigset_t mask)
{
sigset_t saveset;
mask &= _BLOCKABLE;
spin_lock_irq(&current->sighand->siglock);
saveset = current->blocked;
current->saved_sigmask = current->blocked;
siginitset(&current->blocked, mask);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
regs->rax = -EINTR;
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
if (do_signal(regs, &saveset))
return -EINTR;
}
current->state = TASK_INTERRUPTIBLE;
schedule();
set_thread_flag(TIF_RESTORE_SIGMASK);
return -ERESTARTNOHAND;
}
asmlinkage long
@ -508,11 +502,11 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
current->comm, current->pid, frame, regs->rip, frame->pretcode);
#endif
return 1;
return 0;
give_sigsegv:
force_sigsegv(sig, current);
return 0;
return -EFAULT;
}
int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
@ -595,7 +589,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
regs->ss = __USER32_DS;
set_fs(USER_DS);
regs->eflags &= ~TF_MASK;
regs->eflags &= ~TF_MASK;
if (test_thread_flag(TIF_SINGLESTEP))
ptrace_notify(SIGTRAP);
@ -604,9 +598,9 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
current->comm, current->pid, frame, regs->rip, frame->pretcode);
#endif
return 1;
return 0;
give_sigsegv:
force_sigsegv(sig, current);
return 0;
return -EFAULT;
}

82
arch/x86_64/kernel/signal.c
View File

@ -37,37 +37,6 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
int ia32_setup_frame(int sig, struct k_sigaction *ka,
sigset_t *set, struct pt_regs * regs);
asmlinkage long
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(&current->sighand->siglock);
saveset = current->blocked;
current->blocked = newset;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
#ifdef DEBUG_SIG
printk("rt_sigsuspend savset(%lx) newset(%lx) regs(%p) rip(%lx)\n",
saveset, newset, regs, regs->rip);
#endif
regs->rax = -EINTR;
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
if (do_signal(regs, &saveset))
return -EINTR;
}
}
asmlinkage long
sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
struct pt_regs *regs)
@ -341,11 +310,11 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
current->comm, current->pid, frame, regs->rip, frame->pretcode);
#endif
return 1;
return 0;
give_sigsegv:
force_sigsegv(sig, current);
return 0;
return -EFAULT;
}
/*
@ -408,7 +377,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
#endif
ret = setup_rt_frame(sig, ka, info, oldset, regs);
if (ret) {
if (ret == 0) {
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
@ -425,11 +394,12 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
* want to handle. Thus you cannot kill init even with a SIGKILL even by
* mistake.
*/
int do_signal(struct pt_regs *regs, sigset_t *oldset)
static void do_signal(struct pt_regs *regs)
{
struct k_sigaction ka;
siginfo_t info;
int signr;
sigset_t *oldset;
/*
* We want the common case to go fast, which
@ -438,9 +408,11 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
* if so.
*/
if (!user_mode(regs))
return 1;
return;
if (!oldset)
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = &current->saved_sigmask;
else
oldset = &current->blocked;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
@ -454,30 +426,46 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset)
set_debugreg(current->thread.debugreg7, 7);
/* Whee! Actually deliver the signal. */
return handle_signal(signr, &info, &ka, oldset, regs);
if (handle_signal(signr, &info, &ka, oldset, regs) == 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 */
clear_thread_flag(TIF_RESTORE_SIGMASK);
}
return;
}
/* Did we come from a system call? */
if ((long)regs->orig_rax >= 0) {
/* Restart the system call - no handlers present */
long res = regs->rax;
if (res == -ERESTARTNOHAND ||
res == -ERESTARTSYS ||
res == -ERESTARTNOINTR) {
switch (res) {
case -ERESTARTNOHAND:
case -ERESTARTSYS:
case -ERESTARTNOINTR:
regs->rax = regs->orig_rax;
regs->rip -= 2;
}
if (regs->rax == (unsigned long)-ERESTART_RESTARTBLOCK) {
break;
case -ERESTART_RESTARTBLOCK:
regs->rax = test_thread_flag(TIF_IA32) ?
__NR_ia32_restart_syscall :
__NR_restart_syscall;
regs->rip -= 2;
break;
}
}
return 0;
/* 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, &current->saved_sigmask, NULL);
}
}
void do_notify_resume(struct pt_regs *regs, sigset_t *oldset, __u32 thread_info_flags)
void
do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
{
#ifdef DEBUG_SIG
printk("do_notify_resume flags:%x rip:%lx rsp:%lx caller:%lx pending:%lx\n",
@ -491,8 +479,8 @@ void do_notify_resume(struct pt_regs *regs, sigset_t *oldset, __u32 thread_info_
}
/* deal with pending signal delivery */
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(regs,oldset);
if (thread_info_flags & (_TIF_SIGPENDING|_TIF_RESTORE_SIGMASK))
do_signal(regs);
}
void signal_fault(struct pt_regs *regs, void __user *frame, char *where)

4
include/asm-x86_64/signal.h
View File

@ -24,10 +24,6 @@ typedef struct {
} sigset_t;
struct pt_regs;
asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
#else
/* Here we must cater to libcs that poke about in kernel headers. */

2
include/asm-x86_64/thread_info.h
View File

@ -114,6 +114,7 @@ static inline struct thread_info *stack_thread_info(void)
#define TIF_IRET 5 /* force IRET */
#define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */
#define TIF_SECCOMP 8 /* secure computing */
#define TIF_RESTORE_SIGMASK 9 /* restore signal mask in do_signal */
/* 16 free */
#define TIF_IA32 17 /* 32bit process */
#define TIF_FORK 18 /* ret_from_fork */
@ -128,6 +129,7 @@ static inline struct thread_info *stack_thread_info(void)
#define _TIF_IRET (1<<TIF_IRET)
#define _TIF_SYSCALL_AUDIT (1<<TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP (1<<TIF_SECCOMP)
#define _TIF_RESTORE_SIGMASK (1<<TIF_RESTORE_SIGMASK)
#define _TIF_IA32 (1<<TIF_IA32)
#define _TIF_FORK (1<<TIF_FORK)
#define _TIF_ABI_PENDING (1<<TIF_ABI_PENDING)

1
include/asm-x86_64/unistd.h
View File

@ -658,6 +658,7 @@ do { \
#define __ARCH_WANT_SYS_SIGPENDING
#define __ARCH_WANT_SYS_SIGPROCMASK
#define __ARCH_WANT_SYS_RT_SIGACTION
#define __ARCH_WANT_SYS_RT_SIGSUSPEND
#define __ARCH_WANT_SYS_TIME
#define __ARCH_WANT_COMPAT_SYS_TIME