[PATCH 0/5] x86: signal works for unification

[PATCH 0/5] x86: signal works for unification

[Hiroshi Shimamoto]

Hi,

this patch series is for future unification of signal.c.
These patches make common functions similar in signal_32|64.c.

Could you please review them?

thanks,
Hiroshi Shimamoto

[PATCH 1/5] x86_32: signal: use syscall_get_nr and error

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

Use asm/syscall.h interfaces that do the same things.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
 arch/x86/kernel/signal_32.c |    9 +++++----
 1 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index b21070e..3e4a688 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -27,6 +27,7 @@
 #include <asm/uaccess.h>
 #include <asm/i387.h>
 #include <asm/vdso.h>
+#include <asm/syscall.h>
 #include <asm/syscalls.h>
 
 #include "sigframe.h"
@@ -507,9 +508,9 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	int ret;
 
 	/* Are we from a system call? */
-	if ((long)regs->orig_ax >= 0) {
+	if (syscall_get_nr(current, regs) >= 0) {
 		/* If so, check system call restarting.. */
-		switch (regs->ax) {
+		switch (syscall_get_error(current, regs)) {
 		case -ERESTART_RESTARTBLOCK:
 		case -ERESTARTNOHAND:
 			regs->ax = -EINTR;
@@ -623,9 +624,9 @@ static void do_signal(struct pt_regs *regs)
 	}
 
 	/* Did we come from a system call? */
-	if ((long)regs->orig_ax >= 0) {
+	if (syscall_get_nr(current, regs) >= 0) {
 		/* Restart the system call - no handlers present */
-		switch (regs->ax) {
+		switch (syscall_get_error(current, regs)) {
 		case -ERESTARTNOHAND:
 		case -ERESTARTSYS:
 		case -ERESTARTNOINTR:
-- 
1.5.6

[PATCH 2/5] x86_32: signal: introduce signal_fault()

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

implement signal_fault() for 32bit.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
 arch/x86/kernel/signal_32.c |   18 +++++++++++++++++-
 include/asm-x86/ptrace.h    |    4 ++--
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 3e4a688..76d05d7 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -243,7 +243,7 @@ asmlinkage int sys_rt_sigreturn(unsigned long __unused)
 	return ax;
 
 badframe:
-	force_sig(SIGSEGV, current);
+	signal_fault(regs, frame, "rt sigreturn");
 	return 0;
 }
 
@@ -669,3 +669,19 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
 
 	clear_thread_flag(TIF_IRET);
 }
+
+void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
+{
+	struct task_struct *me = current;
+
+	if (show_unhandled_signals && printk_ratelimit()) {
+		printk(KERN_INFO
+		       "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx",
+		       me->comm, me->pid, where, frame,
+		       regs->ip, regs->sp, regs->orig_ax);
+		print_vma_addr(" in ", regs->ip);
+		printk(KERN_CONT "\n");
+	}
+
+	force_sig(SIGSEGV, me);
+}
diff --git a/include/asm-x86/ptrace.h b/include/asm-x86/ptrace.h
index d64a610..4dfce55 100644
--- a/include/asm-x86/ptrace.h
+++ b/include/asm-x86/ptrace.h
@@ -178,10 +178,10 @@ convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs);
 #ifdef CONFIG_X86_32
 extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
 			 int error_code);
-#else
-void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
 #endif
 
+void signal_fault(struct pt_regs *regs, void __user *frame, char *where);
+
 extern long syscall_trace_enter(struct pt_regs *);
 extern void syscall_trace_leave(struct pt_regs *);
 
-- 
1.5.6

[PATCH 3/5] x86: signal: make NR_restart_syscall

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

make NR_restart_syscall macro for cosmetic unification of handle_signal().

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
 arch/x86/kernel/signal_32.c |    3 ++-
 arch/x86/kernel/signal_64.c |    6 +++---
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 76d05d7..bd9b650 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -572,6 +572,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	return 0;
 }
 
+#define NR_restart_syscall	__NR_restart_syscall
 /*
  * Note that 'init' is a special process: it doesn't get signals it doesn't
  * want to handle. Thus you cannot kill init even with a SIGKILL even by
@@ -635,7 +636,7 @@ static void do_signal(struct pt_regs *regs)
 			break;
 
 		case -ERESTART_RESTARTBLOCK:
-			regs->ax = __NR_restart_syscall;
+			regs->ax = NR_restart_syscall;
 			regs->ip -= 2;
 			break;
 		}
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 823a55b..19e2b91 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -362,6 +362,8 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	return ret;
 }
 
+#define NR_restart_syscall	\
+	test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall
 /*
  * Note that 'init' is a special process: it doesn't get signals it doesn't
  * want to handle. Thus you cannot kill init even with a SIGKILL even by
@@ -423,9 +425,7 @@ static void do_signal(struct pt_regs *regs)
 			regs->ip -= 2;
 			break;
 		case -ERESTART_RESTARTBLOCK:
-			regs->ax = test_thread_flag(TIF_IA32) ?
-					__NR_ia32_restart_syscall :
-					__NR_restart_syscall;
+			regs->ax = NR_restart_syscall;
 			regs->ip -= 2;
 			break;
 		}
-- 
1.5.6

[PATCH 4/5] x86: signal: split out frame setups

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

Make setup_rt_frame() and split out frame setups from handle_signal().
This is for cosmetic unification of handle_signal().

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
 arch/x86/kernel/signal_32.c |   29 ++++++++++++++++++++---------
 arch/x86/kernel/signal_64.c |   30 ++++++++++++++++++++----------
 2 files changed, 40 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index bd9b650..48982f7 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -338,8 +338,8 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
 }
 
 static int
-setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
-	    struct pt_regs *regs)
+__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
+	      struct pt_regs *regs)
 {
 	struct sigframe __user *frame;
 	void __user *restorer;
@@ -416,8 +416,8 @@ give_sigsegv:
 	return -EFAULT;
 }
 
-static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
-			  sigset_t *set, struct pt_regs *regs)
+static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+			    sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	void __user *restorer;
@@ -502,6 +502,21 @@ give_sigsegv:
  * OK, we're invoking a handler:
  */
 static int
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+	       sigset_t *set, struct pt_regs *regs)
+{
+	int ret;
+
+	/* Set up the stack frame */
+	if (ka->sa.sa_flags & SA_SIGINFO)
+		ret = __setup_rt_frame(sig, ka, info, set, regs);
+	else
+		ret = __setup_frame(sig, ka, set, regs);
+
+	return ret;
+}
+
+static int
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	      sigset_t *oldset, struct pt_regs *regs)
 {
@@ -537,11 +552,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	    likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
 		regs->flags &= ~X86_EFLAGS_TF;
 
-	/* Set up the stack frame */
-	if (ka->sa.sa_flags & SA_SIGINFO)
-		ret = setup_rt_frame(sig, ka, info, oldset, regs);
-	else
-		ret = setup_frame(sig, ka, oldset, regs);
+	ret = setup_rt_frame(sig, ka, info, oldset, regs);
 
 	if (ret)
 		return ret;
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index 19e2b91..8fbdd23 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -195,8 +195,8 @@ get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
 	return (void __user *)round_down(sp - size, 64);
 }
 
-static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
-			   sigset_t *set, struct pt_regs *regs)
+static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+			    sigset_t *set, struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	void __user *fp = NULL;
@@ -280,6 +280,24 @@ give_sigsegv:
 /*
  * OK, we're invoking a handler
  */
+static int
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+	       sigset_t *set, struct pt_regs *regs)
+{
+	int ret;
+
+#ifdef CONFIG_IA32_EMULATION
+	if (test_thread_flag(TIF_IA32)) {
+		if (ka->sa.sa_flags & SA_SIGINFO)
+			ret = ia32_setup_rt_frame(sig, ka, info, set, regs);
+		else
+			ret = ia32_setup_frame(sig, ka, set, regs);
+	} else
+#endif
+	ret = __setup_rt_frame(sig, ka, info, set, regs);
+
+	return ret;
+}
 
 static int
 handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
@@ -317,14 +335,6 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	    likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
 		regs->flags &= ~X86_EFLAGS_TF;
 
-#ifdef CONFIG_IA32_EMULATION
-	if (test_thread_flag(TIF_IA32)) {
-		if (ka->sa.sa_flags & SA_SIGINFO)
-			ret = ia32_setup_rt_frame(sig, ka, info, oldset, regs);
-		else
-			ret = ia32_setup_frame(sig, ka, oldset, regs);
-	} else
-#endif
 	ret = setup_rt_frame(sig, ka, info, oldset, regs);
 
 	if (ret == 0) {
-- 
1.5.6

[PATCH 5/5] x86_32: signal: move signal number conversion to upper layer

[Hiroshi Shimamoto]

From: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>

Bring signal number conversion in __setup_frame() and __setup_rt_frame()
up into the common part setup_frame().

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
---
 arch/x86/kernel/signal_32.c |   31 ++++++++++++-------------------
 1 files changed, 12 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 48982f7..b668efc 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -344,7 +344,6 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 	struct sigframe __user *frame;
 	void __user *restorer;
 	int err = 0;
-	int usig;
 	void __user *fpstate = NULL;
 
 	frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
@@ -352,13 +351,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		goto give_sigsegv;
 
-	usig = current_thread_info()->exec_domain
-		&& current_thread_info()->exec_domain->signal_invmap
-		&& sig < 32
-		? current_thread_info()->exec_domain->signal_invmap[sig]
-		: sig;
-
-	err = __put_user(usig, &frame->sig);
+	err = __put_user(sig, &frame->sig);
 	if (err)
 		goto give_sigsegv;
 
@@ -422,7 +415,6 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	struct rt_sigframe __user *frame;
 	void __user *restorer;
 	int err = 0;
-	int usig;
 	void __user *fpstate = NULL;
 
 	frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
@@ -430,13 +422,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
 		goto give_sigsegv;
 
-	usig = current_thread_info()->exec_domain
-		&& current_thread_info()->exec_domain->signal_invmap
-		&& sig < 32
-		? current_thread_info()->exec_domain->signal_invmap[sig]
-		: sig;
-
-	err |= __put_user(usig, &frame->sig);
+	err |= __put_user(sig, &frame->sig);
 	err |= __put_user(&frame->info, &frame->pinfo);
 	err |= __put_user(&frame->uc, &frame->puc);
 	err |= copy_siginfo_to_user(&frame->info, info);
@@ -482,7 +468,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	/* Set up registers for signal handler */
 	regs->sp = (unsigned long)frame;
 	regs->ip = (unsigned long)ka->sa.sa_handler;
-	regs->ax = (unsigned long)usig;
+	regs->ax = (unsigned long)sig;
 	regs->dx = (unsigned long)&frame->info;
 	regs->cx = (unsigned long)&frame->uc;
 
@@ -506,12 +492,19 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
 	       sigset_t *set, struct pt_regs *regs)
 {
 	int ret;
+	int usig;
+
+	usig = current_thread_info()->exec_domain
+		&& current_thread_info()->exec_domain->signal_invmap
+		&& sig < 32
+		? current_thread_info()->exec_domain->signal_invmap[sig]
+		: sig;
 
 	/* Set up the stack frame */
 	if (ka->sa.sa_flags & SA_SIGINFO)
-		ret = __setup_rt_frame(sig, ka, info, set, regs);
+		ret = __setup_rt_frame(usig, ka, info, set, regs);
 	else
-		ret = __setup_frame(sig, ka, set, regs);
+		ret = __setup_frame(usig, ka, set, regs);
 
 	return ret;
 }
-- 
1.5.6

Re: [PATCH 0/5] x86: signal works for unification

[Ingo Molnar]

* Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> wrote:

> Hi,
> 
> this patch series is for future unification of signal.c.
> These patches make common functions similar in signal_32|64.c.
> 
> Could you please review them?

looks good to me - it's fairly safely structured and also in small, 
single-purpose steps. If there's a problem with them bisection should 
give a very good clue about exactly where.

So i've created a new tip/x86/signal topic for them and applied them - 
lets see how it goes. Thanks,

	Ingo