Re: [PATCH 1/2] target/hppa: Fix proberi instruction emulation for linux-user

[Helge Deller]

Thank you Denis,

Btw, this patch was already pulled by Richard...

Helge

On 8/22/22 12:31, Denis V. Lunev wrote:
> From: Helge Deller <deller@gmx.de>
>
> The proberi assembler instruction checks the read/write access rights
> for the page of a given address and shall return a value of 1 if the
> test succeeds and a value of 0 on failure in the target register.
>
> But when run in linux-user mode, qemu currently simply returns the
> return code of page_check_range() which returns 0 on success and -1 on
> failure, which is the opposite of what proberi should return.
>
> Fix it by checking the return code of page_check_range() and return the
> expected return value.
>
> The easiest way to reproduce the issue is by running
> "/lib/ld.so.1 --version" in a chroot which fails without this patch.
> At startup of ld.so the __canonicalize_funcptr_for_compare() function is
> used to resolve the function address out of a function descriptor, which
> fails because proberi (due to the wrong return code) seems to indicate
> that the given address isn't accessible.
>
> Signed-off-by: Helge Deller <deller@gmx.de>
> ---
>  target/hppa/op_helper.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/hppa/op_helper.c b/target/hppa/op_helper.c
> index cd304f051e..fbd80e4248 100644
> --- a/target/hppa/op_helper.c
> +++ b/target/hppa/op_helper.c
> @@ -170,7 +170,7 @@ target_ureg HELPER(probe)(CPUHPPAState *env, target_ulong 
> addr,
>                            uint32_t level, uint32_t want)
>  {
>  #ifdef CONFIG_USER_ONLY
> -    return page_check_range(addr, 1, want);
> +    return (page_check_range(addr, 1, want) == 0) ? 1 : 0;
>  #else
>      int prot, excp;
>      hwaddr phys;