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Re: [Qemu-devel] [PATCH] linux-user/syscall.c: Notice about lock bitmask
From: |
Chen Gang |
Subject: |
Re: [Qemu-devel] [PATCH] linux-user/syscall.c: Notice about lock bitmask translation for fcntl |
Date: |
Fri, 18 Dec 2015 14:51:38 +0800 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 |
I found this issue during my working time, it is about sw_64 (almost the
same as alpha) host running i386 wine programs.
I also found another issue, but I am not quite sure whether it is worth
enough for our upstream: The related fix patch is below, which will let
the initialization slower, but for most archs, they have no this issue.
linux-user/mmap.c: Always zero MAP_ANONYMOUS memory in target_mmap()
In some architectures, they have no policy to zero MAP_ANONYMOUS memory,
which will cause issue for qemu target_mmap.
Signed-off-by: Chen Gang <address@hidden>
diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index 7b459d5..9c9152d 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -567,6 +567,10 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int
prot,
printf("\n");
#endif
tb_invalidate_phys_range(start, start + len);
+ if ((prot & PROT_WRITE) && (flags & MAP_ANONYMOUS)
+ && ((flags & MAP_PRIVATE) || (fd == -1))) {
+ memset(g2h(start), 0, len);
+ }
mmap_unlock();
return start;
fail:
Thanks.
On 2015年12月18日 14:26, Chen Gang wrote:
>
> For fcntl, it always needs to notice about it, just like do_fcntl() has
> done, or it will cause issue (e.g. alpha host run i386 guest).
>
> Signed-off-by: Chen Gang <address@hidden>
> ---
> linux-user/syscall.c | 18 ++++++++++++------
> 1 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 0f8adeb..1a60e6f 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -9007,7 +9007,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> if (((CPUARMState *)cpu_env)->eabi) {
> if (!lock_user_struct(VERIFY_READ, target_efl, arg3, 1))
> goto efault;
> - fl.l_type = tswap16(target_efl->l_type);
> + fl.l_type =
> target_to_host_bitmask(tswap16(target_fl->l_type),
> + flock_tbl);
> fl.l_whence = tswap16(target_efl->l_whence);
> fl.l_start = tswap64(target_efl->l_start);
> fl.l_len = tswap64(target_efl->l_len);
> @@ -9018,7 +9019,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> {
> if (!lock_user_struct(VERIFY_READ, target_fl, arg3, 1))
> goto efault;
> - fl.l_type = tswap16(target_fl->l_type);
> + fl.l_type =
> target_to_host_bitmask(tswap16(target_fl->l_type),
> + flock_tbl);
> fl.l_whence = tswap16(target_fl->l_whence);
> fl.l_start = tswap64(target_fl->l_start);
> fl.l_len = tswap64(target_fl->l_len);
> @@ -9031,7 +9033,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> if (((CPUARMState *)cpu_env)->eabi) {
> if (!lock_user_struct(VERIFY_WRITE, target_efl, arg3,
> 0))
> goto efault;
> - target_efl->l_type = tswap16(fl.l_type);
> + target_efl->l_type = host_to_target_bitmask(
> + tswap16(fl.l_type),
> flock_tbl);
> target_efl->l_whence = tswap16(fl.l_whence);
> target_efl->l_start = tswap64(fl.l_start);
> target_efl->l_len = tswap64(fl.l_len);
> @@ -9042,7 +9045,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> {
> if (!lock_user_struct(VERIFY_WRITE, target_fl, arg3, 0))
> goto efault;
> - target_fl->l_type = tswap16(fl.l_type);
> + target_fl->l_type = host_to_target_bitmask(
> + tswap16(fl.l_type),
> flock_tbl);
> target_fl->l_whence = tswap16(fl.l_whence);
> target_fl->l_start = tswap64(fl.l_start);
> target_fl->l_len = tswap64(fl.l_len);
> @@ -9058,7 +9062,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> if (((CPUARMState *)cpu_env)->eabi) {
> if (!lock_user_struct(VERIFY_READ, target_efl, arg3, 1))
> goto efault;
> - fl.l_type = tswap16(target_efl->l_type);
> + fl.l_type =
> target_to_host_bitmask(tswap16(target_fl->l_type),
> + flock_tbl);
> fl.l_whence = tswap16(target_efl->l_whence);
> fl.l_start = tswap64(target_efl->l_start);
> fl.l_len = tswap64(target_efl->l_len);
> @@ -9069,7 +9074,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> {
> if (!lock_user_struct(VERIFY_READ, target_fl, arg3, 1))
> goto efault;
> - fl.l_type = tswap16(target_fl->l_type);
> + fl.l_type =
> target_to_host_bitmask(tswap16(target_fl->l_type),
> + flock_tbl);
> fl.l_whence = tswap16(target_fl->l_whence);
> fl.l_start = tswap64(target_fl->l_start);
> fl.l_len = tswap64(target_fl->l_len);
>
--
Chen Gang (陈刚)
Open, share, and attitude like air, water, and life which God blessed