[Qemu-devel] [PATCH 0/2] linux-user openrisc fixes

[Qemu-devel] [PATCH 0/2] linux-user openrisc fixes

[Richard Henderson]

Both of these fixes are required to fix g++ unwinding tests.


r~


Richard Henderson (2):
  linux-user: Implement signals for openrisc
  linux-user: Fix struct sigaltstack for openrisc

 linux-user/openrisc/target_signal.h  |   2 +-
 linux-user/openrisc/target_syscall.h |  23 +--
 linux-user/openrisc/signal.c         | 210 +++++++++++----------------
 linux-user/signal.c                  |   2 +-
 target/openrisc/cpu.c                |   1 +
 5 files changed, 88 insertions(+), 150 deletions(-)

-- 
2.17.0

[Qemu-devel] [PATCH 1/2] linux-user: Implement signals for openrisc

[Richard Henderson]

All of the existing code was boilerplate from elsewhere,
and would crash the guest upon the first signal.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/openrisc/target_syscall.h |  23 +--
 linux-user/openrisc/signal.c         | 210 +++++++++++----------------
 linux-user/signal.c                  |   2 +-
 target/openrisc/cpu.c                |   1 +
 4 files changed, 87 insertions(+), 149 deletions(-)

diff --git a/linux-user/openrisc/target_syscall.h b/linux-user/openrisc/target_syscall.h
index 03104f80af..f21fab3192 100644
--- a/linux-user/openrisc/target_syscall.h
+++ b/linux-user/openrisc/target_syscall.h
@@ -2,26 +2,9 @@
 #define OPENRISC_TARGET_SYSCALL_H
 
 struct target_pt_regs {
-    union {
-        struct {
-            /* Named registers */
-            uint32_t sr;       /* Stored in place of r0 */
-            target_ulong sp;   /* r1 */
-        };
-        struct {
-            /* Old style */
-            target_ulong offset[2];
-            target_ulong gprs[30];
-        };
-        struct {
-            /* New style */
-            target_ulong gpr[32];
-        };
-    };
-    target_ulong pc;
-    target_ulong orig_gpr11;   /* For restarting system calls */
-    uint32_t syscallno;        /* Syscall number (used by strace) */
-    target_ulong dummy;     /* Cheap alignment fix */
+    abi_ulong gpr[32];
+    abi_ulong pc;
+    abi_ulong sr;
 };
 
 #define UNAME_MACHINE "openrisc"
diff --git a/linux-user/openrisc/signal.c b/linux-user/openrisc/signal.c
index ecf2897ccd..387fa63174 100644
--- a/linux-user/openrisc/signal.c
+++ b/linux-user/openrisc/signal.c
@@ -22,125 +22,79 @@
 #include "signal-common.h"
 #include "linux-user/trace.h"
 
-struct target_sigcontext {
+typedef struct target_sigcontext {
     struct target_pt_regs regs;
     abi_ulong oldmask;
-    abi_ulong usp;
-};
+} target_sigcontext;
 
-struct target_ucontext {
+typedef struct target_ucontext {
     abi_ulong tuc_flags;
     abi_ulong tuc_link;
     target_stack_t tuc_stack;
-    struct target_sigcontext tuc_mcontext;
+    target_sigcontext tuc_mcontext;
     target_sigset_t tuc_sigmask;   /* mask last for extensibility */
-};
+} target_ucontext;
 
-struct target_rt_sigframe {
-    abi_ulong pinfo;
-    uint64_t puc;
+typedef struct target_rt_sigframe {
     struct target_siginfo info;
-    struct target_sigcontext sc;
-    struct target_ucontext uc;
-    unsigned char retcode[16];  /* trampoline code */
-};
+    target_ucontext uc;
+    uint32_t retcode[4];  /* trampoline code */
+} target_rt_sigframe;
 
-/* This is the asm-generic/ucontext.h version */
-#if 0
-static int restore_sigcontext(CPUOpenRISCState *regs,
-                              struct target_sigcontext *sc)
+static void restore_sigcontext(CPUOpenRISCState *env, target_sigcontext *sc)
 {
-    unsigned int err = 0;
-    unsigned long old_usp;
+    int i;
+    abi_ulong v;
 
-    /* Alwys make any pending restarted system call return -EINTR */
-    current_thread_info()->restart_block.fn = do_no_restart_syscall;
-
-    /* restore the regs from &sc->regs (same as sc, since regs is first)
-     * (sc is already checked for VERIFY_READ since the sigframe was
-     *  checked in sys_sigreturn previously)
-     */
-
-    if (copy_from_user(regs, &sc, sizeof(struct target_pt_regs))) {
-        goto badframe;
+    for (i = 0; i < 32; ++i) {
+        __get_user(v, &sc->regs.gpr[i]);
+        cpu_set_gpr(env, i, v);
     }
+    __get_user(env->pc, &sc->regs.pc);
 
-    /* make sure the U-flag is set so user-mode cannot fool us */
-
-    regs->sr &= ~SR_SM;
-
-    /* restore the old USP as it was before we stacked the sc etc.
-     * (we cannot just pop the sigcontext since we aligned the sp and
-     *  stuff after pushing it)
-     */
-
-    __get_user(old_usp, &sc->usp);
-    phx_signal("old_usp 0x%lx", old_usp);
-
-    __PHX__ REALLY           /* ??? */
-    wrusp(old_usp);
-    regs->gpr[1] = old_usp;
-
-    /* TODO: the other ports use regs->orig_XX to disable syscall checks
-     * after this completes, but we don't use that mechanism. maybe we can
-     * use it now ?
-     */
-
-    return err;
-
-badframe:
-    return 1;
+    /* Make sure the supervisor flag is clear.  */
+    __get_user(v, &sc->regs.sr);
+    cpu_set_sr(env, v & ~SR_SM);
 }
-#endif
 
 /* Set up a signal frame.  */
 
-static void setup_sigcontext(struct target_sigcontext *sc,
-                             CPUOpenRISCState *regs,
-                             unsigned long mask)
+static void setup_sigcontext(target_sigcontext *sc, CPUOpenRISCState *env)
 {
-    unsigned long usp = cpu_get_gpr(regs, 1);
+    int i;
 
-    /* copy the regs. they are first in sc so we can use sc directly */
+    for (i = 0; i < 32; ++i) {
+        __put_user(cpu_get_gpr(env, i), &sc->regs.gpr[i]);
+    }
 
-    /*copy_to_user(&sc, regs, sizeof(struct target_pt_regs));*/
-
-    /* Set the frametype to CRIS_FRAME_NORMAL for the execution of
-       the signal handler. The frametype will be restored to its previous
-       value in restore_sigcontext. */
-    /*regs->frametype = CRIS_FRAME_NORMAL;*/
-
-    /* then some other stuff */
-    __put_user(mask, &sc->oldmask);
-    __put_user(usp, &sc->usp);
+    __put_user(env->pc, &sc->regs.pc);
+    __put_user(cpu_get_sr(env), &sc->regs.sr);
 }
 
-static inline unsigned long align_sigframe(unsigned long sp)
+static inline target_ulong align_sigframe(target_ulong sp)
 {
-    return sp & ~3UL;
+    return QEMU_ALIGN_DOWN(sp, 4);
 }
 
 static inline abi_ulong get_sigframe(struct target_sigaction *ka,
-                                     CPUOpenRISCState *regs,
+                                     CPUOpenRISCState *env,
                                      size_t frame_size)
 {
-    unsigned long sp = get_sp_from_cpustate(regs);
+    target_ulong sp = get_sp_from_cpustate(env);
     int onsigstack = on_sig_stack(sp);
 
-    /* redzone */
-    sp = target_sigsp(sp, ka);
-
+    /* Honor redzone now.  If we swap to signal stack, no need to waste
+     * the 128 bytes by subtracting afterward.
+     */
+    sp = target_sigsp(sp - 128, ka);
     sp = align_sigframe(sp - frame_size);
 
-    /*
-     * If we are on the alternate signal stack and would overflow it, don't.
+    /* If we are on the alternate signal stack and would overflow it, don't.
      * Return an always-bogus address instead so we will die with SIGSEGV.
      */
-
-    if (onsigstack && !likely(on_sig_stack(sp))) {
+    if (onsigstack && !on_sig_stack(sp)) {
         return -1L;
     }
-
     return sp;
 }
 
@@ -148,11 +102,8 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
                     target_siginfo_t *info,
                     target_sigset_t *set, CPUOpenRISCState *env)
 {
-    int err = 0;
     abi_ulong frame_addr;
-    unsigned long return_ip;
-    struct target_rt_sigframe *frame;
-    abi_ulong info_addr, uc_addr;
+    target_rt_sigframe *frame;
 
     frame_addr = get_sigframe(ka, env, sizeof(*frame));
     trace_user_setup_rt_frame(env, frame_addr);
@@ -160,47 +111,32 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
         goto give_sigsegv;
     }
 
-    info_addr = frame_addr + offsetof(struct target_rt_sigframe, info);
-    __put_user(info_addr, &frame->pinfo);
-    uc_addr = frame_addr + offsetof(struct target_rt_sigframe, uc);
-    __put_user(uc_addr, &frame->puc);
+    tswap_siginfo(&frame->info, info);
 
-    if (ka->sa_flags & SA_SIGINFO) {
-        tswap_siginfo(&frame->info, info);
-    }
-
-    /*err |= __clear_user(&frame->uc, offsetof(ucontext_t, uc_mcontext));*/
     __put_user(0, &frame->uc.tuc_flags);
     __put_user(0, &frame->uc.tuc_link);
+
     target_save_altstack(&frame->uc.tuc_stack, env);
-    setup_sigcontext(&frame->sc, env, set->sig[0]);
+    setup_sigcontext(&frame->uc.tuc_mcontext, env);
 
-    /*err |= copy_to_user(frame->uc.tuc_sigmask, set, sizeof(*set));*/
-
-    /* trampoline - the desired return ip is the retcode itself */
-    return_ip = (unsigned long)&frame->retcode;
-    /* This is l.ori r11,r0,__NR_sigreturn, l.sys 1 */
-    __put_user(0xa960, (short *)(frame->retcode + 0));
-    __put_user(TARGET_NR_rt_sigreturn, (short *)(frame->retcode + 2));
-    __put_user(0x20000001, (unsigned long *)(frame->retcode + 4));
-    __put_user(0x15000000, (unsigned long *)(frame->retcode + 8));
-
-    if (err) {
-        goto give_sigsegv;
-    }
-
-    /* TODO what is the current->exec_domain stuff and invmap ? */
+    /* This is l.ori r11,r0,__NR_sigreturn; l.sys 1; l.nop; l.nop */
+    __put_user(0xa9600000 | TARGET_NR_rt_sigreturn, frame->retcode + 0);
+    __put_user(0x20000001, frame->retcode + 1);
+    __put_user(0x15000000, frame->retcode + 2);
+    __put_user(0x15000000, frame->retcode + 3);
 
     /* Set up registers for signal handler */
-    env->pc = (unsigned long)ka->_sa_handler; /* what we enter NOW */
-    cpu_set_gpr(env, 9, (unsigned long)return_ip);     /* what we enter LATER */
-    cpu_set_gpr(env, 3, (unsigned long)sig);           /* arg 1: signo */
-    cpu_set_gpr(env, 4, (unsigned long)&frame->info);  /* arg 2: (siginfo_t*) */
-    cpu_set_gpr(env, 5, (unsigned long)&frame->uc);    /* arg 3: ucontext */
-
-    /* actually move the usp to reflect the stacked frame */
-    cpu_set_gpr(env, 1, (unsigned long)frame);
+    cpu_set_gpr(env, 9, frame_addr + offsetof(target_rt_sigframe, retcode));
+    cpu_set_gpr(env, 3, sig);
+    cpu_set_gpr(env, 4, frame_addr + offsetof(target_rt_sigframe, info));
+    cpu_set_gpr(env, 5, frame_addr + offsetof(target_rt_sigframe, uc));
+    cpu_set_gpr(env, 1, frame_addr);
 
+    /* For debugging convenience, set ppc to the insn that faulted.  */
+    env->ppc = env->pc;
+    /* When setting the PC for the signal handler, exit delay slot.  */
+    env->pc = ka->_sa_handler;
+    env->dflag = 0;
     return;
 
 give_sigsegv:
@@ -208,16 +144,34 @@ give_sigsegv:
     force_sigsegv(sig);
 }
 
-long do_sigreturn(CPUOpenRISCState *env)
-{
-    trace_user_do_sigreturn(env, 0);
-    fprintf(stderr, "do_sigreturn: not implemented\n");
-    return -TARGET_ENOSYS;
-}
-
 long do_rt_sigreturn(CPUOpenRISCState *env)
 {
+    abi_ulong frame_addr = cpu_get_gpr(env, 1);
+    target_rt_sigframe *frame;
+    sigset_t set;
+
     trace_user_do_rt_sigreturn(env, 0);
-    fprintf(stderr, "do_rt_sigreturn: not implemented\n");
-    return -TARGET_ENOSYS;
+    if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
+        goto badframe;
+    }
+    if (frame_addr & 3) {
+        goto badframe;
+    }
+
+    target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
+    set_sigmask(&set);
+
+    restore_sigcontext(env, &frame->uc.tuc_mcontext);
+    if (do_sigaltstack(frame_addr + offsetof(target_rt_sigframe, uc.tuc_stack),
+                       0, frame_addr) == -EFAULT) {
+        goto badframe;
+    }
+
+    unlock_user_struct(frame, frame_addr, 0);
+    return cpu_get_gpr(env, 11);
+
+ badframe:
+    unlock_user_struct(frame, frame_addr, 0);
+    force_sig(TARGET_SIGSEGV);
+    return 0;
 }
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 01de433e3a..a8d1f7a284 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -237,7 +237,7 @@ int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset)
     return 0;
 }
 
-#if !defined(TARGET_OPENRISC) && !defined(TARGET_NIOS2)
+#if !defined(TARGET_NIOS2)
 /* Just set the guest's signal mask to the specified value; the
  * caller is assumed to have called block_signals() already.
  */
diff --git a/target/openrisc/cpu.c b/target/openrisc/cpu.c
index d1ef4c737c..7648a74636 100644
--- a/target/openrisc/cpu.c
+++ b/target/openrisc/cpu.c
@@ -28,6 +28,7 @@ static void openrisc_cpu_set_pc(CPUState *cs, vaddr value)
     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
 
     cpu->env.pc = value;
+    cpu->env.dflag = 0;
 }
 
 static bool openrisc_cpu_has_work(CPUState *cs)
-- 
2.17.0

[Qemu-devel] [PATCH 2/2] linux-user: Fix struct sigaltstack for openrisc

[Richard Henderson]

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/openrisc/target_signal.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/linux-user/openrisc/target_signal.h b/linux-user/openrisc/target_signal.h
index 2a4e00b035..901097972a 100644
--- a/linux-user/openrisc/target_signal.h
+++ b/linux-user/openrisc/target_signal.h
@@ -7,8 +7,8 @@
 
 typedef struct target_sigaltstack {
     abi_long ss_sp;
+    abi_int ss_flags;
     abi_ulong ss_size;
-    abi_long ss_flags;
 } target_stack_t;
 
 /* sigaltstack controls  */
-- 
2.17.0

Re: [Qemu-devel] [PATCH 2/2] linux-user: Fix struct sigaltstack for openrisc

[Laurent Vivier]

Le 31/05/2018 à 06:18, Richard Henderson a écrit :
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/openrisc/target_signal.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/linux-user/openrisc/target_signal.h b/linux-user/openrisc/target_signal.h
> index 2a4e00b035..901097972a 100644
> --- a/linux-user/openrisc/target_signal.h
> +++ b/linux-user/openrisc/target_signal.h
> @@ -7,8 +7,8 @@
>  
>  typedef struct target_sigaltstack {
>      abi_long ss_sp;
> +    abi_int ss_flags;
>      abi_ulong ss_size;
> -    abi_long ss_flags;
>  } target_stack_t;
>  
>  /* sigaltstack controls  */
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>

Re: [Qemu-devel] [PATCH 1/2] linux-user: Implement signals for openrisc

[Laurent Vivier]

Le 31/05/2018 à 06:18, Richard Henderson a écrit :
> All of the existing code was boilerplate from elsewhere,
> and would crash the guest upon the first signal.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/openrisc/target_syscall.h |  23 +--
>  linux-user/openrisc/signal.c         | 210 +++++++++++----------------
>  linux-user/signal.c                  |   2 +-
>  target/openrisc/cpu.c                |   1 +
>  4 files changed, 87 insertions(+), 149 deletions(-)
> 
> diff --git a/linux-user/openrisc/target_syscall.h b/linux-user/openrisc/target_syscall.h
> index 03104f80af..f21fab3192 100644
> --- a/linux-user/openrisc/target_syscall.h
> +++ b/linux-user/openrisc/target_syscall.h
> @@ -2,26 +2,9 @@
>  #define OPENRISC_TARGET_SYSCALL_H
>  
>  struct target_pt_regs {
> -    union {
> -        struct {
> -            /* Named registers */
> -            uint32_t sr;       /* Stored in place of r0 */
> -            target_ulong sp;   /* r1 */
> -        };
> -        struct {
> -            /* Old style */
> -            target_ulong offset[2];
> -            target_ulong gprs[30];
> -        };
> -        struct {
> -            /* New style */
> -            target_ulong gpr[32];
> -        };
> -    };
> -    target_ulong pc;
> -    target_ulong orig_gpr11;   /* For restarting system calls */
> -    uint32_t syscallno;        /* Syscall number (used by strace) */
> -    target_ulong dummy;     /* Cheap alignment fix */
> +    abi_ulong gpr[32];
> +    abi_ulong pc;
> +    abi_ulong sr;
>  };

>From where is this coming from?

In linux/arch/openrisc/include/asm/ptrace.h, we have the definition you
remove.

Thanks,
Laurent

Re: [Qemu-devel] [PATCH 1/2] linux-user: Implement signals for openrisc

[Richard Henderson]

On 06/01/2018 12:59 PM, Laurent Vivier wrote:
> Le 31/05/2018 à 06:18, Richard Henderson a écrit :
>> All of the existing code was boilerplate from elsewhere,
>> and would crash the guest upon the first signal.
>>
>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
>> ---
>>  linux-user/openrisc/target_syscall.h |  23 +--
>>  linux-user/openrisc/signal.c         | 210 +++++++++++----------------
>>  linux-user/signal.c                  |   2 +-
>>  target/openrisc/cpu.c                |   1 +
>>  4 files changed, 87 insertions(+), 149 deletions(-)
>>
>> diff --git a/linux-user/openrisc/target_syscall.h b/linux-user/openrisc/target_syscall.h
>> index 03104f80af..f21fab3192 100644
>> --- a/linux-user/openrisc/target_syscall.h
>> +++ b/linux-user/openrisc/target_syscall.h
>> @@ -2,26 +2,9 @@
>>  #define OPENRISC_TARGET_SYSCALL_H
>>  
>>  struct target_pt_regs {
>> -    union {
>> -        struct {
>> -            /* Named registers */
>> -            uint32_t sr;       /* Stored in place of r0 */
>> -            target_ulong sp;   /* r1 */
>> -        };
>> -        struct {
>> -            /* Old style */
>> -            target_ulong offset[2];
>> -            target_ulong gprs[30];
>> -        };
>> -        struct {
>> -            /* New style */
>> -            target_ulong gpr[32];
>> -        };
>> -    };
>> -    target_ulong pc;
>> -    target_ulong orig_gpr11;   /* For restarting system calls */
>> -    uint32_t syscallno;        /* Syscall number (used by strace) */
>> -    target_ulong dummy;     /* Cheap alignment fix */
>> +    abi_ulong gpr[32];
>> +    abi_ulong pc;
>> +    abi_ulong sr;
>>  };
> 
> From where is this coming from?
> 
> In linux/arch/openrisc/include/asm/ptrace.h, we have the definition you
> remove.

I'm using the one from .../include/uapi/asm/ptrace.h.
I now see that they have two different names -- this one is struct
user_regs_struct -- but this is also what is used by sigcontext.

I should fix the names too to avoid confusion.


r~

Re: [Qemu-devel] [PATCH 1/2] linux-user: Implement signals for openrisc

[Laurent Vivier]

Le 31/05/2018 à 06:18, Richard Henderson a écrit :
> All of the existing code was boilerplate from elsewhere,
> and would crash the guest upon the first signal.
> 
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/openrisc/target_syscall.h |  23 +--
>  linux-user/openrisc/signal.c         | 210 +++++++++++----------------
>  linux-user/signal.c                  |   2 +-
>  target/openrisc/cpu.c                |   1 +
>  4 files changed, 87 insertions(+), 149 deletions(-)
> 
...
> @@ -148,11 +102,8 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
>                      target_siginfo_t *info,
>                      target_sigset_t *set, CPUOpenRISCState *env)
>  {
...
> @@ -160,47 +111,32 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
>          goto give_sigsegv;
>      }
>  
> -    info_addr = frame_addr + offsetof(struct target_rt_sigframe, info);
> -    __put_user(info_addr, &frame->pinfo);
> -    uc_addr = frame_addr + offsetof(struct target_rt_sigframe, uc);
> -    __put_user(uc_addr, &frame->puc);
> +    tswap_siginfo(&frame->info, info);
>  
> -    if (ka->sa_flags & SA_SIGINFO) {
> -        tswap_siginfo(&frame->info, info);
> -    }

Why do you remove the "ka->sa_flags & SA_SIGINFO"?

> -    /*err |= __clear_user(&frame->uc, offsetof(ucontext_t, uc_mcontext));*/
>      __put_user(0, &frame->uc.tuc_flags);
>      __put_user(0, &frame->uc.tuc_link);
> +
>      target_save_altstack(&frame->uc.tuc_stack, env);
> -    setup_sigcontext(&frame->sc, env, set->sig[0]);
> +    setup_sigcontext(&frame->uc.tuc_mcontext, env);
>  
> -    /*err |= copy_to_user(frame->uc.tuc_sigmask, set, sizeof(*set));*/

other targets have something like:

    for (i = 0; i < TARGET_NSIG_WORDS; i++) {
        __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
    }

to match kernel

        err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));

Do we need it?

Thanks,
Laurent

Re: [Qemu-devel] [PATCH 1/2] linux-user: Implement signals for openrisc

[Richard Henderson]

On 06/01/2018 01:45 PM, Laurent Vivier wrote:
> Le 31/05/2018 à 06:18, Richard Henderson a écrit :
>> All of the existing code was boilerplate from elsewhere,
>> and would crash the guest upon the first signal.
>>
>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
>> ---
>>  linux-user/openrisc/target_syscall.h |  23 +--
>>  linux-user/openrisc/signal.c         | 210 +++++++++++----------------
>>  linux-user/signal.c                  |   2 +-
>>  target/openrisc/cpu.c                |   1 +
>>  4 files changed, 87 insertions(+), 149 deletions(-)
>>
> ...
>> @@ -148,11 +102,8 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
>>                      target_siginfo_t *info,
>>                      target_sigset_t *set, CPUOpenRISCState *env)
>>  {
> ...
>> @@ -160,47 +111,32 @@ void setup_rt_frame(int sig, struct target_sigaction *ka,
>>          goto give_sigsegv;
>>      }
>>  
>> -    info_addr = frame_addr + offsetof(struct target_rt_sigframe, info);
>> -    __put_user(info_addr, &frame->pinfo);
>> -    uc_addr = frame_addr + offsetof(struct target_rt_sigframe, uc);
>> -    __put_user(uc_addr, &frame->puc);
>> +    tswap_siginfo(&frame->info, info);
>>  
>> -    if (ka->sa_flags & SA_SIGINFO) {
>> -        tswap_siginfo(&frame->info, info);
>> -    }
> 
> Why do you remove the "ka->sa_flags & SA_SIGINFO"?

I thought it was unconditional for rt signals, which are the only ones that
openrisc has.  It's definitely odd, since the kernel also checks that flag, but
unconditionally points r4 to the (possibly uninitialized) siginfo_t.

>> -    /*err |= copy_to_user(frame->uc.tuc_sigmask, set, sizeof(*set));*/
> 
> other targets have something like:
> 
>     for (i = 0; i < TARGET_NSIG_WORDS; i++) {
>         __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
>     }
> 
> to match kernel
> 
>         err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
> 
> Do we need it?

Yes, this is my mistake.


r~