Re: [PATCH v2 1/1] linux-user/signal: Decode waitid si_code

From: Laurent Vivier <laurent@vivier.eu>
To: Alistair Francis <alistair.francis@wdc.com>,
	qemu-devel@nongnu.org, qemu-riscv@nongnu.org,
	dilfridge@gentoo.org
Cc: alistair23@gmail.com, bmeng.cn@gmail.com, palmer@dabbelt.com
Subject: Re: [PATCH v2 1/1] linux-user/signal: Decode waitid si_code
Date: Sat, 13 Feb 2021 17:15:52 +0100	[thread overview]
Message-ID: <3f824b7e-2de3-1bc1-6393-433824085119@vivier.eu> (raw)
In-Reply-To: <1fb2d56aa23a81f4473e638abe9e2d78c09a3d5b.1611080607.git.alistair.francis@wdc.com>

Le 19/01/2021 à 19:24, Alistair Francis a écrit :
> When mapping the host waitid status to the target status we previously
> just used decoding information in the status value. This doesn't follow
> what the waitid documentation describes, which instead suggests using
> the si_code value for the decoding. This results in the incorrect values
> seen when calling waitid. This is especially apparent on RV32 where all
> wait calls use waitid (see the bug case).
> 
> This patch just passes the waitid status directly back to the guest.
> 
> Buglink: https://bugs.launchpad.net/qemu/+bug/1906193
> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
> ---
> v2:
>  - Set tinfo->_sifields._sigchld._status directly from status
> 
>  linux-user/signal.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/linux-user/signal.c b/linux-user/signal.c
> index 73de934c65..7eecec46c4 100644
> --- a/linux-user/signal.c
> +++ b/linux-user/signal.c
> @@ -349,8 +349,7 @@ static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo,
>          case TARGET_SIGCHLD:
>              tinfo->_sifields._sigchld._pid = info->si_pid;
>              tinfo->_sifields._sigchld._uid = info->si_uid;
> -            tinfo->_sifields._sigchld._status
> -                = host_to_target_waitstatus(info->si_status);
> +            tinfo->_sifields._sigchld._status = info->si_status;
>              tinfo->_sifields._sigchld._utime = info->si_utime;
>              tinfo->_sifields._sigchld._stime = info->si_stime;
>              si_type = QEMU_SI_CHLD;
> 

Applied to my linux-user-for-6.0 branch.

Thanks,
Laurent