[PATCH] target/hppa: Fix random 32-bit linux-user crashes

[PATCH] target/hppa: Fix random 32-bit linux-user crashes

[Helge Deller]

The linux-user hppa target crashes randomly for me since commit
081a0ed188d8 ("target/hppa: Do not mask in copy_iaoq_entry").

That commit dropped the masking of the IAOQ addresses while copying them
from other registers and instead keeps them with all 64 bits up until
the full gva is formed with the help of hppa_form_gva_psw().

So, when running in linux-user mode on an emulated 64-bit CPU, we need
to mask to a 32-bit address space at the very end in hppa_form_gva_psw()
if the PSW-W flag isn't set (which is the case for linux-user on hppa).

Fixes: 081a0ed188d8 ("target/hppa: Do not mask in copy_iaoq_entry")
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/target/hppa/cpu.h b/target/hppa/cpu.h
index 2bcb3b602b..56d9568d6c 100644
--- a/target/hppa/cpu.h
+++ b/target/hppa/cpu.h
@@ -319,7 +319,7 @@ static inline target_ulong hppa_form_gva_psw(target_ulong psw, uint64_t spc,
                                              target_ulong off)
 {
 #ifdef CONFIG_USER_ONLY
-    return off;
+    return off & gva_offset_mask(psw);
 #else
     return spc | (off & gva_offset_mask(psw));
 #endif

Re: [PATCH] target/hppa: Fix random 32-bit linux-user crashes

[Richard Henderson]

On 9/3/24 09:41, Helge Deller wrote:
> The linux-user hppa target crashes randomly for me since commit
> 081a0ed188d8 ("target/hppa: Do not mask in copy_iaoq_entry").
> 
> That commit dropped the masking of the IAOQ addresses while copying them
> from other registers and instead keeps them with all 64 bits up until
> the full gva is formed with the help of hppa_form_gva_psw().
> 
> So, when running in linux-user mode on an emulated 64-bit CPU, we need
> to mask to a 32-bit address space at the very end in hppa_form_gva_psw()
> if the PSW-W flag isn't set (which is the case for linux-user on hppa).
> 
> Fixes: 081a0ed188d8 ("target/hppa: Do not mask in copy_iaoq_entry")
> Signed-off-by: Helge Deller <deller@gmx.de>
> 
> diff --git a/target/hppa/cpu.h b/target/hppa/cpu.h
> index 2bcb3b602b..56d9568d6c 100644
> --- a/target/hppa/cpu.h
> +++ b/target/hppa/cpu.h
> @@ -319,7 +319,7 @@ static inline target_ulong hppa_form_gva_psw(target_ulong psw, uint64_t spc,
>                                                target_ulong off)
>   {
>   #ifdef CONFIG_USER_ONLY
> -    return off;
> +    return off & gva_offset_mask(psw);
>   #else
>       return spc | (off & gva_offset_mask(psw));
>   #endif

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~