From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58904) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9wds-0000PU-Jj for qemu-devel@nongnu.org; Fri, 18 Dec 2015 10:08:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a9wdp-0004N0-C8 for qemu-devel@nongnu.org; Fri, 18 Dec 2015 10:08:24 -0500 Received: from mout.kundenserver.de ([212.227.17.24]:60833) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a9wdp-0004Mh-3G for qemu-devel@nongnu.org; Fri, 18 Dec 2015 10:08:21 -0500 References: <1448275106-21493-1-git-send-email-laurent@vivier.eu> From: Laurent Vivier Message-ID: <56742158.3020903@vivier.eu> Date: Fri, 18 Dec 2015 16:08:08 +0100 MIME-Version: 1.0 In-Reply-To: <1448275106-21493-1-git-send-email-laurent@vivier.eu> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH] linux-user, sh4: fix signal retcode address List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: riku.voipio@iki.fi, glaubitz@physik.fu-berlin.de Ping ? Le 23/11/2015 11:38, Laurent Vivier a écrit : > To return from a signal, setup_frame() puts an instruction to > be executed in the stack. This sequence calls the syscall sigreturn(). > > The address of the instruction must be set in the PR register > to be executed. > > This patch fixes this: the current code sets the register to the address > of the instruction in the host address space (which can be 64bit whereas > PR is only 32bit), but the virtual CPU can't access this address space, > so we put in PR the address of the instruction in the guest address space. > > This patch also removes an useless variable (ret) in the modified functions. > > Signed-off-by: Laurent Vivier > --- > linux-user/signal.c | 16 ++++++---------- > 1 file changed, 6 insertions(+), 10 deletions(-) > > diff --git a/linux-user/signal.c b/linux-user/signal.c > index 55e5405..5e8f6d8 100644 > --- a/linux-user/signal.c > +++ b/linux-user/signal.c > @@ -3215,7 +3215,6 @@ static void setup_frame(int sig, struct target_sigaction *ka, > struct target_sigframe *frame; > abi_ulong frame_addr; > int i; > - int err = 0; > > frame_addr = get_sigframe(ka, regs->gregs[15], sizeof(*frame)); > if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) > @@ -3233,15 +3232,14 @@ static void setup_frame(int sig, struct target_sigaction *ka, > regs->pr = (unsigned long) ka->sa_restorer; > } else { > /* Generate return code (system call to sigreturn) */ > + abi_ulong retcode_addr = frame_addr + > + offsetof(struct target_sigframe, retcode); > __put_user(MOVW(2), &frame->retcode[0]); > __put_user(TRAP_NOARG, &frame->retcode[1]); > __put_user((TARGET_NR_sigreturn), &frame->retcode[2]); > - regs->pr = (unsigned long) frame->retcode; > + regs->pr = (unsigned long) retcode_addr; > } > > - if (err) > - goto give_sigsegv; > - > /* Set up registers for signal handler */ > regs->gregs[15] = frame_addr; > regs->gregs[4] = sig; /* Arg for signal handler */ > @@ -3264,7 +3262,6 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka, > struct target_rt_sigframe *frame; > abi_ulong frame_addr; > int i; > - int err = 0; > > frame_addr = get_sigframe(ka, regs->gregs[15], sizeof(*frame)); > if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) > @@ -3293,15 +3290,14 @@ static void setup_rt_frame(int sig, struct target_sigaction *ka, > regs->pr = (unsigned long) ka->sa_restorer; > } else { > /* Generate return code (system call to sigreturn) */ > + abi_ulong retcode_addr = frame_addr + > + offsetof(struct target_rt_sigframe, retcode); > __put_user(MOVW(2), &frame->retcode[0]); > __put_user(TRAP_NOARG, &frame->retcode[1]); > __put_user((TARGET_NR_rt_sigreturn), &frame->retcode[2]); > - regs->pr = (unsigned long) frame->retcode; > + regs->pr = (unsigned long) retcode_addr; > } > > - if (err) > - goto give_sigsegv; > - > /* Set up registers for signal handler */ > regs->gregs[15] = frame_addr; > regs->gregs[4] = sig; /* Arg for signal handler */ >