FW: [uml-devel] Minor problems with interrupted systemcalls

[Stroesser, B. <Bod...@fu...>]

Once again due to a typo: the correct text is "NO systemcall restart is
done", instead of  "do systemcall restart is done"

Sorry

Bodo

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If a program is traced or debugged, in 2.6.x interrupted systemcalls
with the results -ERESTARTxxxxxxx are not handled correctly, do
systemcall restart is done.

Here is a patch that should fix the problem. The patch is tested on
2.6.6 in tt and skas modes. It applies to 2.6.8.1, but I've not tested
yet.

Hope, this helps.

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Bodo

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--- uml_orig/arch/um/kernel/signal_kern.c 2004-08-05 18:36:24.000000000
+0200

+++ uml/arch/um/kernel/signal_kern.c      2004-09-17 15:03:30.441065600
+0200

@@ -132,19 +132,18 @@

 {

      siginfo_t info;

      struct k_sigaction *ka;

-     int err, sig;

+     int sig;

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      if (!oldset)

            oldset =3D &current->blocked;

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      sig =3D get_signal_to_deliver(&info, regs, NULL);

-     if(sig =3D=3D 0)

-           return(0);

-

-     /* Whee!  Actually deliver the signal.  */

-     ka =3D &current->sighand->action[sig -1 ];

-     err =3D handle_signal(regs, sig, ka, &info, oldset, error);

-     if(!err) return(1);

+     if(sig > 0) {

+           /* Whee!  Actually deliver the signal.  */

+           ka =3D &current->sighand->action[sig -1 ];

+           handle_signal(regs, sig, ka, &info, oldset, error);

+           return(1);

+     }

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      /* Did we come from a system call? */

      if(PT_REGS_SYSCALL_NR(regs) >=3D 0){

--- uml_orig/arch/um/kernel/skas/process.c      2004-08-05
18:36:24.000000000 +0200

+++ uml/arch/um/kernel/skas/process.c     2004-09-17 17:35:09.236250499
+0200

@@ -63,7 +63,7 @@

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      syscall_nr =3D PT_SYSCALL_NR(regs->skas.regs);

      UPT_SYSCALL_NR(regs) =3D syscall_nr;

-     if(syscall_nr < 1){

+     if(syscall_nr < 0){

            relay_signal(SIGTRAP, regs);

            return;

      }

--- uml_orig/arch/um/kernel/skas/syscall_user.c 2004-08-05
18:36:24.000000000 +0200

+++ uml/arch/um/kernel/skas/syscall_user.c      2004-09-17
18:52:50.655271683 +0200

@@ -10,10 +10,6 @@

 #include "sysdep/ptrace.h"

 #include "sysdep/sigcontext.h"

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-/* XXX Bogus */

-#define ERESTARTSYS    512

-#define ERESTARTNOINTR 513

-#define ERESTARTNOHAND 514

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 void handle_syscall(union uml_pt_regs *regs)

 {

@@ -26,9 +22,6 @@

      result =3D execute_syscall(regs);

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      REGS_SET_SYSCALL_RETURN(regs->skas.regs, result);

-     if((result =3D=3D -ERESTARTNOHAND) || (result =3D=3D -ERESTARTSYS) =
||=20

-        (result =3D=3D -ERESTARTNOINTR))

-           do_signal(result);

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      syscall_trace(regs, 0);

      record_syscall_end(index, result);

--- uml_orig/arch/um/kernel/tt/syscall_user.c   2004-08-05
18:36:24.000000000 +0200

+++ uml/arch/um/kernel/tt/syscall_user.c  2004-09-17 18:52:41.978671390
+0200

@@ -17,10 +17,6 @@

 #include "syscall_user.h"

 #include "tt.h"

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-/* XXX Bogus */

-#define ERESTARTSYS    512

-#define ERESTARTNOINTR 513

-#define ERESTARTNOHAND 514

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 void syscall_handler_tt(int sig, union uml_pt_regs *regs)

 {

@@ -42,9 +38,6 @@

      UPT_SC(regs) =3D sc;

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      SC_SET_SYSCALL_RETURN(sc, result);

-     if((result =3D=3D -ERESTARTNOHAND) || (result =3D=3D -ERESTARTSYS) =
||=20

-        (result =3D=3D -ERESTARTNOINTR))

-           do_signal(result);

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      syscall_trace(regs, 0);

      record_syscall_end(index, result);

@@ -63,7 +56,7 @@

      regs =3D TASK_REGS(task);

      UPT_SYSCALL_NR(regs) =3D syscall;

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-     if(syscall < 1) return(0);

+     if(syscall < 0) return(0);

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      if((syscall !=3D __NR_sigreturn) &&

         ((unsigned long *) PT_IP(proc_regs) >=3D &_stext) &&=20

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