[Qemu-devel] [PATCH 0/5] linux-user for-usptream patches

[Qemu-devel] [PATCH 0/5] linux-user for-usptream patches

[Riku Voipio]

From: Riku Voipio <riku.voipio@nokia.com>

Some fixes to avoid hanging, make arm uname match selected
cpu, and fixes to cp15.c13 registers for linux-user tls register
access.

Loïc Minier (1):
  linux-user: adapt uname machine to emulated CPU

Riku Voipio (4):
  fix locking error with current_tb
  linux-user: remove signal handler before calling abort()
  linux-user: Add access to TLS registers
  target-arm: Thread ID Registers are ARMv6K +

 Makefile.target        |    2 +-
 exec.c                 |   13 +++++++-
 linux-user/cpu-uname.c |   72 ++++++++++++++++++++++++++++++++++++++++++++++++
 linux-user/cpu-uname.h |    1 +
 linux-user/syscall.c   |    3 +-
 target-arm/helper.c    |   39 +++++++++++++++++++++++++-
 6 files changed, 125 insertions(+), 5 deletions(-)
 create mode 100644 linux-user/cpu-uname.c
 create mode 100644 linux-user/cpu-uname.

[Qemu-devel] [PATCH 1/5] linux-user: adapt uname machine to emulated CPU

[Riku Voipio]

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From: Loïc Minier <lool@dooz.org>

This patch for linux-user adapts the output of the emulated uname()
syscall to match the configured CPU.  Tested with x86, x86-64 and arm
emulation.

Signed-off-by: Loïc Minier <lool@dooz.org>
Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
---
 Makefile.target        |    2 +-
 linux-user/cpu-uname.c |   72 ++++++++++++++++++++++++++++++++++++++++++++++++
 linux-user/cpu-uname.h |    1 +
 linux-user/syscall.c   |    3 +-
 4 files changed, 76 insertions(+), 2 deletions(-)
 create mode 100644 linux-user/cpu-uname.c
 create mode 100644 linux-user/cpu-uname.h

diff --git a/Makefile.target b/Makefile.target
index 5c0ef1f..9dfc4c2 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -95,7 +95,7 @@ $(call set-vpath, $(SRC_PATH)/linux-user:$(SRC_PATH)/linux-user/$(TARGET_ABI_DIR
 
 QEMU_CFLAGS+=-I$(SRC_PATH)/linux-user -I$(SRC_PATH)/linux-user/$(TARGET_ABI_DIR)
 obj-y = main.o syscall.o strace.o mmap.o signal.o thunk.o \
-      elfload.o linuxload.o uaccess.o gdbstub.o
+      elfload.o linuxload.o uaccess.o gdbstub.o cpu-uname.o
 
 obj-$(TARGET_HAS_BFLT) += flatload.o
 obj-$(TARGET_HAS_ELFLOAD32) += elfload32.o
diff --git a/linux-user/cpu-uname.c b/linux-user/cpu-uname.c
new file mode 100644
index 0000000..23afede
--- /dev/null
+++ b/linux-user/cpu-uname.c
@@ -0,0 +1,72 @@
+/*
+ *  cpu to uname machine name map
+ *
+ *  Copyright (c) 2009 Loïc Minier
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+
+#include "qemu.h"
+//#include "qemu-common.h"
+#include "cpu-uname.h"
+
+/* return highest utsname machine name for emulated instruction set
+ *
+ * NB: the default emulated CPU ("any") might not match any existing CPU, e.g.
+ * on ARM it has all features turned on, so there is no perfect arch string to
+ * return here */
+const char *cpu_to_uname_machine(void *cpu_env)
+{
+#ifdef TARGET_ARM
+    /* utsname machine name on linux arm is CPU arch name + endianness, e.g.
+     * armv7l; to get a list of CPU arch names from the linux source, use:
+     *     grep arch_name: -A1 linux/arch/arm/mm/proc-*.S
+     * see arch/arm/kernel/setup.c: setup_processor()
+     *
+     * to test by CPU id, compare cpu_env->cp15.c0_cpuid to ARM_CPUID_*
+     * defines and to test by CPU feature, use arm_feature(cpu_env,
+     * ARM_FEATURE_*) */
+
+    /* in theory, endianness is configurable on some ARM CPUs, but this isn't
+     * used in user mode emulation */
+#ifdef TARGET_WORDS_BIGENDIAN
+#define utsname_suffix "b"
+#else
+#define utsname_suffix "l"
+#endif
+    if (arm_feature(cpu_env, ARM_FEATURE_V7))
+        return "armv7" utsname_suffix;
+    if (arm_feature(cpu_env, ARM_FEATURE_V6))
+        return "armv6" utsname_suffix;
+    /* earliest emulated CPU is ARMv5TE; qemu can emulate the 1026, but not its
+     * Jazelle support */
+    return "armv5te" utsname_suffix;
+#elif defined(TARGET_X86_64)
+    return "x86-64";
+#elif defined(TARGET_I386)
+    /* see arch/x86/kernel/cpu/bugs.c: check_bugs(), 386, 486, 586, 686 */
+    uint32_t cpuid_version = ((CPUX86State *)cpu_env)->cpuid_version;
+    int family = ((cpuid_version >> 8) & 0x0f) + ((cpuid_version >> 20) & 0xff);
+    if (family == 4)
+        return "i486";
+    if (family == 5)
+        return "i586";
+    return "i686";
+#else
+    /* default is #define-d in each arch/ subdir */
+    return UNAME_MACHINE;
+#endif
+}
diff --git a/linux-user/cpu-uname.h b/linux-user/cpu-uname.h
new file mode 100644
index 0000000..32492de
--- /dev/null
+++ b/linux-user/cpu-uname.h
@@ -0,0 +1 @@
+const char *cpu_to_uname_machine(void *cpu_env);
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index f2dd39e..9fb493f 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -82,6 +82,7 @@
 #include <linux/fb.h>
 #include <linux/vt.h>
 #include "linux_loop.h"
+#include "cpu-uname.h"
 
 #include "qemu.h"
 #include "qemu-common.h"
@@ -5739,7 +5740,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             if (!is_error(ret)) {
                 /* Overrite the native machine name with whatever is being
                    emulated. */
-                strcpy (buf->machine, UNAME_MACHINE);
+                strcpy (buf->machine, cpu_to_uname_machine(cpu_env));
                 /* Allow the user to override the reported release.  */
                 if (qemu_uname_release && *qemu_uname_release)
                   strcpy (buf->release, qemu_uname_release);
-- 
1.6.5

[Qemu-devel] [PATCH 2/5] fix locking error with current_tb

[Riku Voipio]

From: Riku Voipio <riku.voipio@nokia.com>

Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
---
 exec.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/exec.c b/exec.c
index 1190591..71f655f 100644
--- a/exec.c
+++ b/exec.c
@@ -1537,15 +1537,15 @@ static void cpu_unlink_tb(CPUState *env)
     TranslationBlock *tb;
     static spinlock_t interrupt_lock = SPIN_LOCK_UNLOCKED;
 
+    spin_lock(&interrupt_lock);
     tb = env->current_tb;
     /* if the cpu is currently executing code, we must unlink it and
        all the potentially executing TB */
     if (tb) {
-        spin_lock(&interrupt_lock);
         env->current_tb = NULL;
         tb_reset_jump_recursive(tb);
-        spin_unlock(&interrupt_lock);
     }
+    spin_unlock(&interrupt_lock);
 }
 
 /* mask must never be zero, except for A20 change call */
-- 
1.6.5

[Qemu-devel] [PATCH 3/5] linux-user: remove signal handler before calling abort()

[Riku Voipio]

From: Riku Voipio <riku.voipio@nokia.com>

Qemu may hang in host_signal_handler after qemu has done a
seppuku with cpu_abort(). But at this stage we are not really
interested in target process coredump anymore, so unregister
host_signal_handler to die grafefully.

Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
---
 exec.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/exec.c b/exec.c
index 71f655f..3145b83 100644
--- a/exec.c
+++ b/exec.c
@@ -40,6 +40,7 @@
 #include "kvm.h"
 #if defined(CONFIG_USER_ONLY)
 #include <qemu.h>
+#include <signal.h>
 #endif
 
 //#define DEBUG_TB_INVALIDATE
@@ -1692,6 +1693,14 @@ void cpu_abort(CPUState *env, const char *fmt, ...)
     }
     va_end(ap2);
     va_end(ap);
+#if defined(CONFIG_USER_ONLY)
+    {
+        struct sigaction act;
+        sigfillset(&act.sa_mask);
+        act.sa_handler = SIG_DFL;
+        sigaction(SIGABRT, &act, NULL);
+    }
+#endif
     abort();
 }
 
-- 
1.6.5

[Qemu-devel] [PATCH 4/5] linux-user: Add access to TLS registers

[Riku Voipio]

From: Riku Voipio <riku.voipio@nokia.com>

If you compile applications with gcc -mtp=cp15, __thread
access's will generate an abort. Implement accessing allowed
cp15.c13 registers on ARMv6K+ in linux-user.

Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
---
 target-arm/helper.c |   27 ++++++++++++++++++++++++++-
 1 files changed, 26 insertions(+), 1 deletions(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index b3aec99..68578ce 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -505,13 +505,38 @@ uint32_t HELPER(get_cp)(CPUState *env, uint32_t insn)
 
 void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val)
 {
+    int op2;
+
+    op2 = (insn >> 5) & 7;
+    /* Allow write access to CP15 User RW Thread ID Register */
+    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
+        switch (op2) {
+        case 2:
+            env->cp15.c13_tls1 = val;
+            return;
+        }
+    }
     cpu_abort(env, "cp15 insn %08x\n", insn);
 }
 
 uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn)
 {
+    int op2;
+    /* Allow read access to CP15 User RW and RO Thread ID Registers */
+
+    op2 = (insn >> 5) & 7;
+    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
+        switch (op2) {
+        case 2:
+            return env->cp15.c13_tls1;
+        case 3:
+            return env->cp15.c13_tls2;
+        default:
+            goto bad_reg;
+        }
+    }
+bad_reg:
     cpu_abort(env, "cp15 insn %08x\n", insn);
-    return 0;
 }
 
 /* These should probably raise undefined insn exceptions.  */
-- 
1.6.5

[Qemu-devel] [PATCH 5/5] target-arm: Thread ID Registers are ARMv6K +

[Riku Voipio]

From: Riku Voipio <riku.voipio@nokia.com>

Change the system-emulation code also to only support accessing
the cp15.c13 Thread ID registers on ARMv6K and newer.

Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
---
 target-arm/helper.c |   12 ++++++++++++
 1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index 68578ce..1245d9d 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -1517,12 +1517,18 @@ void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val)
             env->cp15.c13_context = val;
             break;
         case 2:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             env->cp15.c13_tls1 = val;
             break;
         case 3:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             env->cp15.c13_tls2 = val;
             break;
         case 4:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             env->cp15.c13_tls3 = val;
             break;
         default:
@@ -1805,10 +1811,16 @@ uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn)
         case 1:
             return env->cp15.c13_context;
         case 2:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             return env->cp15.c13_tls1;
         case 3:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             return env->cp15.c13_tls2;
         case 4:
+            if (!arm_feature(env, ARM_FEATURE_V6K))
+                goto bad_reg;
             return env->cp15.c13_tls3;
         default:
             goto bad_reg;
-- 
1.6.5

Re: [Qemu-devel] [PATCH 4/5] linux-user: Add access to TLS registers

[Laurent Desnogues]

On Tue, Jan 26, 2010 at 5:00 PM, Riku Voipio <riku.voipio@iki.fi> wrote:
> From: Riku Voipio <riku.voipio@nokia.com>
>
> If you compile applications with gcc -mtp=cp15, __thread
> access's will generate an abort. Implement accessing allowed
> cp15.c13 registers on ARMv6K+ in linux-user.
>
> Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
> ---
>  target-arm/helper.c |   27 ++++++++++++++++++++++++++-
>  1 files changed, 26 insertions(+), 1 deletions(-)
>
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index b3aec99..68578ce 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -505,13 +505,38 @@ uint32_t HELPER(get_cp)(CPUState *env, uint32_t insn)
>
>  void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val)
>  {
> +    int op2;
> +
> +    op2 = (insn >> 5) & 7;
> +    /* Allow write access to CP15 User RW Thread ID Register */
> +    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
> +        switch (op2) {
> +        case 2:
> +            env->cp15.c13_tls1 = val;
> +            return;
> +        }
> +    }
>     cpu_abort(env, "cp15 insn %08x\n", insn);
>  }
>
>  uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn)
>  {
> +    int op2;
> +    /* Allow read access to CP15 User RW and RO Thread ID Registers */
> +
> +    op2 = (insn >> 5) & 7;
> +    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
> +        switch (op2) {
> +        case 2:
> +            return env->cp15.c13_tls1;
> +        case 3:
> +            return env->cp15.c13_tls2;
> +        default:
> +            goto bad_reg;
> +        }
> +    }
> +bad_reg:
>     cpu_abort(env, "cp15 insn %08x\n", insn);
> -    return 0;
>  }
>
>  /* These should probably raise undefined insn exceptions.  */

Most of the checks you do here could be done in translate.c.
Wouldn't it be better to do them there?


Laurent

Re: [Qemu-devel] [PATCH 5/5] target-arm: Thread ID Registers are ARMv6K +

[Laurent Desnogues]

On Tue, Jan 26, 2010 at 5:00 PM, Riku Voipio <riku.voipio@iki.fi> wrote:
> From: Riku Voipio <riku.voipio@nokia.com>
>
> Change the system-emulation code also to only support accessing
> the cp15.c13 Thread ID registers on ARMv6K and newer.
>
> Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
> ---
>  target-arm/helper.c |   12 ++++++++++++
>  1 files changed, 12 insertions(+), 0 deletions(-)
>
> diff --git a/target-arm/helper.c b/target-arm/helper.c
> index 68578ce..1245d9d 100644
> --- a/target-arm/helper.c
> +++ b/target-arm/helper.c
> @@ -1517,12 +1517,18 @@ void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val)
>             env->cp15.c13_context = val;
>             break;
>         case 2:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             env->cp15.c13_tls1 = val;
>             break;
>         case 3:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             env->cp15.c13_tls2 = val;
>             break;
>         case 4:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             env->cp15.c13_tls3 = val;
>             break;
>         default:
> @@ -1805,10 +1811,16 @@ uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn)
>         case 1:
>             return env->cp15.c13_context;
>         case 2:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             return env->cp15.c13_tls1;
>         case 3:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             return env->cp15.c13_tls2;
>         case 4:
> +            if (!arm_feature(env, ARM_FEATURE_V6K))
> +                goto bad_reg;
>             return env->cp15.c13_tls3;
>         default:
>             goto bad_reg;

Same question as for user mode :-)


Laurent

Re: [Qemu-devel] [PATCH 4/5] linux-user: Add access to TLS registers

[Riku Voipio]

On Tue, Jan 26, 2010 at 05:27:27PM +0100, Laurent Desnogues wrote:
> On Tue, Jan 26, 2010 at 5:00 PM, Riku Voipio <riku.voipio@iki.fi> wrote:
> > From: Riku Voipio <riku.voipio@nokia.com>
> >
> > If you compile applications with gcc -mtp=cp15, __thread
> > access's will generate an abort. Implement accessing allowed
> > cp15.c13 registers on ARMv6K+ in linux-user.
> >
> > Signed-off-by: Riku Voipio <riku.voipio@nokia.com>
> > ---
> >  target-arm/helper.c |   27 ++++++++++++++++++++++++++-
> >  1 files changed, 26 insertions(+), 1 deletions(-)
> >
> > diff --git a/target-arm/helper.c b/target-arm/helper.c
> > index b3aec99..68578ce 100644
> > --- a/target-arm/helper.c
> > +++ b/target-arm/helper.c
> > @@ -505,13 +505,38 @@ uint32_t HELPER(get_cp)(CPUState *env, uint32_t insn)
> >
> >  void HELPER(set_cp15)(CPUState *env, uint32_t insn, uint32_t val)
> >  {
> > +    int op2;
> > +
> > +    op2 = (insn >> 5) & 7;
> > +    /* Allow write access to CP15 User RW Thread ID Register */
> > +    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
> > +        switch (op2) {
> > +        case 2:
> > +            env->cp15.c13_tls1 = val;
> > +            return;
> > +        }
> > +    }
> >     cpu_abort(env, "cp15 insn %08x\n", insn);
> >  }
> >
> >  uint32_t HELPER(get_cp15)(CPUState *env, uint32_t insn)
> >  {
> > +    int op2;
> > +    /* Allow read access to CP15 User RW and RO Thread ID Registers */
> > +
> > +    op2 = (insn >> 5) & 7;
> > +    if (arm_feature (env, ARM_FEATURE_V6K) && ((insn >> 16) & 0xf) == 13) {
> > +        switch (op2) {
> > +        case 2:
> > +            return env->cp15.c13_tls1;
> > +        case 3:
> > +            return env->cp15.c13_tls2;
> > +        default:
> > +            goto bad_reg;
> > +        }
> > +    }
> > +bad_reg:
> >     cpu_abort(env, "cp15 insn %08x\n", insn);
> > -    return 0;
> >  }
> >
> >  /* These should probably raise undefined insn exceptions.  */

> Most of the checks you do here could be done in translate.c.
> Wouldn't it be better to do them there?

Indeed, thus we could even avoid the helper completly. I just followed the the
cp15 implementation of system-qemu here.