Re: [Qemu-devel] [PATCH] linux-user/mmap.c: Set prot page flags for the correct region in mmap_frag()

[Chen Gang <chengang@emindsoft.com.cn>]

Oh, sorry, for the coding style issues. Also the typo in the comments. I
shall send patch v2, next.

This fix patch can let the old ACDSee.exe, and the latest WinRAR.exe
setup programs run successfully under real WinXP system dlls.

Thanks.

On 2015年12月31日 15:14, chengang@emindsoft.com.cn wrote:
> From: Chen Gang <chengang@emindsoft.com.cn>
> 
> mmap() size in mmap_frag() is qemu_host_page_size, but the outside calls
> page_set_flags() may be not with qemu_host_page_size. So after mmap(),
> call page_set_flags() in time.
> 
> Also let addr increasing step be TARGET_PAGE_SIZE, just like another
> areas have done.
> 
> Also remote redundant varialbe p.
> 
> Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
> ---
>  linux-user/mmap.c |   10 ++++++----
>  1 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/linux-user/mmap.c b/linux-user/mmap.c
> index 445e8c6..7920c5e 100644
> --- a/linux-user/mmap.c
> +++ b/linux-user/mmap.c
> @@ -151,17 +151,19 @@ static int mmap_frag(abi_ulong real_start,
>  
>      /* get the protection of the target pages outside the mapping */
>      prot1 = 0;
> -    for(addr = real_start; addr < real_end; addr++) {
> +    for(addr = real_start; addr < real_end; addr += TARGET_PAGE_SIZE) {
>          if (addr < start || addr >= end)
>              prot1 |= page_get_flags(addr);
>      }
>  
>      if (prot1 == 0) {
>          /* no page was there, so we allocate one */
> -        void *p = mmap(host_start, qemu_host_page_size, prot,
> -                       flags | MAP_ANONYMOUS, -1, 0);
> -        if (p == MAP_FAILED)
> +        if (mmap(host_start, qemu_host_page_size, prot, flags | MAP_ANONYMOUS,
> +                 -1, 0) == MAP_FAILED) {
>              return -1;
> +        }
> +        page_set_flags(real_start, real_start + qemu_host_page_size,
> +                       prot | PAGE_VALID);
>          prot1 = prot;
>      }
>      prot1 &= PAGE_BITS;
> 

-- 
Chen Gang (陈刚)

Open, share, and attitude like air, water, and life which God blessed