[Qemu-devel] [PATCH] linux-user: fix TARGET_NR_select

[Laurent Vivier]

TARGET_NR_select can have three different implementations:

  1- to always return -ENOSYS

     microblaze, ppc, ppc64

     -> TARGET_WANT_NI_OLD_SELECT

  2- to take parameters from a structure pointed by arg1
    (kernel sys_old_select)

     i386, arm, m68k

     -> TARGET_WANT_OLD_SYS_SELECT

  3- to take parameters from arg[1-5]
     (kernel sys_select)

     x86_64, alpha, s390x,
     cris, sparc, sparc64

Some (new) architectures don't define NR_select,

  4- but only NR__newselect with sys_select:

      mips, mips64, sh

  5- don't define NR__newselect, and use pselect6 syscall:

      aarch64, openrisc, tilegx, unicore32

Reported-by: Timothy Pearson <address@hidden>
Reported-by: Allan Wirth <address@hidden>
Suggested-by: Peter Maydell <address@hidden>
Signed-off-by: Laurent Vivier <address@hidden>
---
 linux-user/arm/target_syscall.h        |  2 ++
 linux-user/i386/target_syscall.h       |  2 ++
 linux-user/m68k/target_syscall.h       |  2 ++
 linux-user/microblaze/target_syscall.h |  2 ++
 linux-user/openrisc/syscall_nr.h       |  2 --
 linux-user/ppc/target_syscall.h        |  2 ++
 linux-user/sh4/syscall_nr.h            |  2 +-
 linux-user/syscall.c                   | 48 ++++++++++++++++++++++------------
 linux-user/tilegx/syscall_nr.h         |  1 -
 9 files changed, 42 insertions(+), 21 deletions(-)

diff --git a/linux-user/arm/target_syscall.h b/linux-user/arm/target_syscall.h
index 11077b7..b1073bf 100644
--- a/linux-user/arm/target_syscall.h
+++ b/linux-user/arm/target_syscall.h
@@ -33,4 +33,6 @@ struct target_pt_regs {
 #define TARGET_MLOCKALL_MCL_CURRENT 1
 #define TARGET_MLOCKALL_MCL_FUTURE  2
 
+#define TARGET_WANT_OLD_SYS_SELECT
+
 #endif  /* TARGET_SYSCALL_H */
diff --git a/linux-user/i386/target_syscall.h b/linux-user/i386/target_syscall.h
index 0ac84dc..6678763 100644
--- a/linux-user/i386/target_syscall.h
+++ b/linux-user/i386/target_syscall.h
@@ -154,4 +154,6 @@ struct target_vm86plus_struct {
 #define TARGET_MLOCKALL_MCL_CURRENT 1
 #define TARGET_MLOCKALL_MCL_FUTURE  2
 
+#define TARGET_WANT_OLD_SYS_SELECT
+
 #endif  /* TARGET_SYSCALL_H */
diff --git a/linux-user/m68k/target_syscall.h b/linux-user/m68k/target_syscall.h
index 97a4cc0..5e2ccf1 100644
--- a/linux-user/m68k/target_syscall.h
+++ b/linux-user/m68k/target_syscall.h
@@ -24,6 +24,8 @@ struct target_pt_regs {
 #define TARGET_MLOCKALL_MCL_CURRENT 1
 #define TARGET_MLOCKALL_MCL_FUTURE  2
 
+#define TARGET_WANT_OLD_SYS_SELECT
+
 void do_m68k_simcall(CPUM68KState *, int);
 
 #endif  /* TARGET_SYSCALL_H */
diff --git a/linux-user/microblaze/target_syscall.h 
b/linux-user/microblaze/target_syscall.h
index 3c1ed27..65b07c2 100644
--- a/linux-user/microblaze/target_syscall.h
+++ b/linux-user/microblaze/target_syscall.h
@@ -53,4 +53,6 @@ struct target_pt_regs {
 #define TARGET_MLOCKALL_MCL_CURRENT 1
 #define TARGET_MLOCKALL_MCL_FUTURE  2
 
+#define TARGET_WANT_NI_OLD_SELECT
+
 #endif
diff --git a/linux-user/openrisc/syscall_nr.h b/linux-user/openrisc/syscall_nr.h
index 6b1c7d2..04059d0 100644
--- a/linux-user/openrisc/syscall_nr.h
+++ b/linux-user/openrisc/syscall_nr.h
@@ -459,8 +459,6 @@
 #define TARGET_NR_getdents 1065
 #define __ARCH_WANT_SYS_GETDENTS
 #define TARGET_NR_futimesat 1066
-#define TARGET_NR_select 1067
-#define __ARCH_WANT_SYS_SELECT
 #define TARGET_NR_poll 1068
 #define TARGET_NR_epoll_wait 1069
 #define TARGET_NR_ustat 1070
diff --git a/linux-user/ppc/target_syscall.h b/linux-user/ppc/target_syscall.h
index 7ca83c2..6616678 100644
--- a/linux-user/ppc/target_syscall.h
+++ b/linux-user/ppc/target_syscall.h
@@ -75,4 +75,6 @@ struct target_revectored_struct {
 #define TARGET_MLOCKALL_MCL_CURRENT 0x2000
 #define TARGET_MLOCKALL_MCL_FUTURE  0x4000
 
+#define TARGET_WANT_NI_OLD_SELECT
+
 #endif  /* TARGET_SYSCALL_H */
diff --git a/linux-user/sh4/syscall_nr.h b/linux-user/sh4/syscall_nr.h
index 5009984..e99f735 100644
--- a/linux-user/sh4/syscall_nr.h
+++ b/linux-user/sh4/syscall_nr.h
@@ -84,7 +84,7 @@
 #define TARGET_NR_settimeofday  79
 #define TARGET_NR_getgroups             80
 #define TARGET_NR_setgroups             81
-#define TARGET_NR_select                82
+                                         /* 82 was sys_oldselect */
 #define TARGET_NR_symlink               83
 #define TARGET_NR_oldlstat              84
 #define TARGET_NR_readlink              85
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 37f0660..e7ec2d3 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -1255,6 +1255,29 @@ static abi_long do_select(int n,
 
     return ret;
 }
+
+#if defined(TARGET_WANT_OLD_SYS_SELECT)
+static abi_long do_old_select(abi_ulong arg1)
+{
+    struct target_sel_arg_struct *sel;
+    abi_ulong inp, outp, exp, tvp;
+    long nsel;
+
+    if (!lock_user_struct(VERIFY_READ, sel, arg1, 1)) {
+        return -TARGET_EFAULT;
+    }
+
+    nsel = tswapal(sel->n);
+    inp = tswapal(sel->inp);
+    outp = tswapal(sel->outp);
+    exp = tswapal(sel->exp);
+    tvp = tswapal(sel->tvp);
+
+    unlock_user_struct(sel, arg1, 0);
+
+    return do_select(nsel, inp, outp, exp, tvp);
+}
+#endif
 #endif
 
 static abi_long do_pipe2(int host_pipe[], int flags)
@@ -8372,24 +8395,15 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
         break;
 #if defined(TARGET_NR_select)
     case TARGET_NR_select:
-#if defined(TARGET_S390X) || defined(TARGET_ALPHA)
-        ret = do_select(arg1, arg2, arg3, arg4, arg5);
+#if defined(TARGET_WANT_NI_OLD_SELECT)
+        /* some architectures used to have old_select here
+         * but now ENOSYS it.
+         */
+        ret = -TARGET_ENOSYS;
+#elif defined(TARGET_WANT_OLD_SYS_SELECT)
+        ret = do_old_select(arg1);
 #else
-        {
-            struct target_sel_arg_struct *sel;
-            abi_ulong inp, outp, exp, tvp;
-            long nsel;
-
-            if (!lock_user_struct(VERIFY_READ, sel, arg1, 1))
-                goto efault;
-            nsel = tswapal(sel->n);
-            inp = tswapal(sel->inp);
-            outp = tswapal(sel->outp);
-            exp = tswapal(sel->exp);
-            tvp = tswapal(sel->tvp);
-            unlock_user_struct(sel, arg1, 0);
-            ret = do_select(nsel, inp, outp, exp, tvp);
-        }
+        ret = do_select(arg1, arg2, arg3, arg4, arg5);
 #endif
         break;
 #endif
diff --git a/linux-user/tilegx/syscall_nr.h b/linux-user/tilegx/syscall_nr.h
index 87fb72c..b86f0fc 100644
--- a/linux-user/tilegx/syscall_nr.h
+++ b/linux-user/tilegx/syscall_nr.h
@@ -311,7 +311,6 @@
 #define TARGET_NR_creat                         1064
 #define TARGET_NR_getdents                      1065
 #define TARGET_NR_futimesat                     1066
-#define TARGET_NR_select                        1067
 #define TARGET_NR_poll                          1068
 #define TARGET_NR_epoll_wait                    1069
 #define TARGET_NR_ustat                         1070
-- 
2.5.5