[PATCH] linux-user/hppa: Detect glibc ABORT_INSTRUCTION and EXCP_BREAK handler

[PATCH] linux-user/hppa: Detect glibc ABORT_INSTRUCTION and EXCP_BREAK handler

[Helge Deller]

The glibc on the hppa platform uses the "iitlbp %r0,(%sr0, %r0)"
assembler instruction as ABORT_INSTRUCTION.
If this (in userspace context) illegal assembler statement is found,
dump the registers and report the failure to userspace the same way as
the Linux kernel on physical hardware.

For other illegal instructions report TARGET_ILL_ILLOPC instead of
TARGET_ILL_ILLOPN as si_code.

Additionally add the missing EXCP_BREAK exception handler which occurs
when the "break x,y" assembler instruction is executed and report
EXCP_ASSIST traps.

Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/linux-user/hppa/cpu_loop.c b/linux-user/hppa/cpu_loop.c
index 98c51e9b8b..a42c34e549 100644
--- a/linux-user/hppa/cpu_loop.c
+++ b/linux-user/hppa/cpu_loop.c
@@ -196,15 +196,20 @@ void cpu_loop(CPUHPPAState *env)
             force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, env->iaoq_f);
             break;
         case EXCP_ILL:
-            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
-            force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->iaoq_f);
+            EXCP_DUMP(env, "qemu: EXCP_ILL exception %#x\n", trapnr);
+            force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
             break;
         case EXCP_PRIV_OPR:
-            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
-            force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
+            /* check for glibc ABORT_INSTRUCTION "iitlbp %r0,(%sr0, %r0)" */
+            EXCP_DUMP(env, "qemu: EXCP_PRIV_OPR exception %#x\n", trapnr);
+            if (env->cr[CR_IIR] == 0x04000000) {
+		    force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
+            } else {
+		    force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
+            }
             break;
         case EXCP_PRIV_REG:
-            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
+            EXCP_DUMP(env, "qemu: EXCP_PRIV_REG exception %#x\n", trapnr);
             force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVREG, env->iaoq_f);
             break;
         case EXCP_OVERFLOW:
@@ -216,6 +221,10 @@ void cpu_loop(CPUHPPAState *env)
         case EXCP_ASSIST:
             force_sig_fault(TARGET_SIGFPE, 0, env->iaoq_f);
             break;
+        case EXCP_BREAK:
+            EXCP_DUMP(env, "qemu: EXCP_BREAK exception %#x\n", trapnr);
+            force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f & ~3);
+            break;
         case EXCP_DEBUG:
             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f);
             break;

Re: [PATCH] linux-user/hppa: Detect glibc ABORT_INSTRUCTION and EXCP_BREAK handler

[Laurent Vivier]

Le 27/10/2022 à 08:58, Helge Deller a écrit :
> The glibc on the hppa platform uses the "iitlbp %r0,(%sr0, %r0)"
> assembler instruction as ABORT_INSTRUCTION.
> If this (in userspace context) illegal assembler statement is found,
> dump the registers and report the failure to userspace the same way as
> the Linux kernel on physical hardware.
> 
> For other illegal instructions report TARGET_ILL_ILLOPC instead of
> TARGET_ILL_ILLOPN as si_code.
> 
> Additionally add the missing EXCP_BREAK exception handler which occurs
> when the "break x,y" assembler instruction is executed and report
> EXCP_ASSIST traps.
> 
> Signed-off-by: Helge Deller <deller@gmx.de>
> 
> diff --git a/linux-user/hppa/cpu_loop.c b/linux-user/hppa/cpu_loop.c
> index 98c51e9b8b..a42c34e549 100644
> --- a/linux-user/hppa/cpu_loop.c
> +++ b/linux-user/hppa/cpu_loop.c
> @@ -196,15 +196,20 @@ void cpu_loop(CPUHPPAState *env)
>               force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, env->iaoq_f);
>               break;
>           case EXCP_ILL:
> -            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
> -            force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->iaoq_f);
> +            EXCP_DUMP(env, "qemu: EXCP_ILL exception %#x\n", trapnr);
> +            force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
>               break;
>           case EXCP_PRIV_OPR:
> -            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
> -            force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
> +            /* check for glibc ABORT_INSTRUCTION "iitlbp %r0,(%sr0, %r0)" */
> +            EXCP_DUMP(env, "qemu: EXCP_PRIV_OPR exception %#x\n", trapnr);
> +            if (env->cr[CR_IIR] == 0x04000000) {
> +		    force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
> +            } else {
> +		    force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
> +            }
>               break;
>           case EXCP_PRIV_REG:
> -            EXCP_DUMP(env, "qemu: got CPU exception 0x%x - aborting\n", trapnr);
> +            EXCP_DUMP(env, "qemu: EXCP_PRIV_REG exception %#x\n", trapnr);
>               force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVREG, env->iaoq_f);
>               break;
>           case EXCP_OVERFLOW:
> @@ -216,6 +221,10 @@ void cpu_loop(CPUHPPAState *env)
>           case EXCP_ASSIST:
>               force_sig_fault(TARGET_SIGFPE, 0, env->iaoq_f);
>               break;
> +        case EXCP_BREAK:
> +            EXCP_DUMP(env, "qemu: EXCP_BREAK exception %#x\n", trapnr);
> +            force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f & ~3);
> +            break;
>           case EXCP_DEBUG:
>               force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f);
>               break;
> 

Applied to my linux-user-for-7.2 branch.

Thanks,
Laurent