From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932933AbcFLMfa (ORCPT ); Sun, 12 Jun 2016 08:35:30 -0400 Received: from szxga04-in.huawei.com ([119.145.14.52]:52206 "EHLO szxga04-in.huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1750964AbcFLMf2 (ORCPT ); Sun, 12 Jun 2016 08:35:28 -0400 Subject: Re: [PATCH 21/23] arm64: ilp32: introduce ilp32-specific handlers for sigframe and ucontext To: Yury Norov , , , , , , , , References: <1464048292-30136-1-git-send-email-ynorov@caviumnetworks.com> <1464048292-30136-22-git-send-email-ynorov@caviumnetworks.com> <5752BCC8.7080205@huawei.com> CC: , , , , , , , , , , , , , , "Andrew Pinski" , Andrew Pinski , Hanjun Guo , "Zhangjian (Bamvor)" From: "Zhangjian (Bamvor)" Message-ID: <575D56DF.8080203@huawei.com> Date: Sun, 12 Jun 2016 20:34:39 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <5752BCC8.7080205@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.111.72.170] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.575D56EE.008E,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 17951ba79ac8b4969aa89c8fe62dfbac Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ping On 2016/6/4 19:34, Zhangjian (Bamvor) wrote: > Hi, > > I found an issue of unwind with the following code. The correct backtrace > should be: > (gdb) where > #0 0x004004d0 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func2 (num=0) at test_force3.c:22 > #3 0x00400540 in func1 (num=1) at test_force3.c:28 > #4 0x00400574 in main (argc=1, argv=0xffd7bc04) at test_force3.c:33 > > Without my patch, the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > With my patch which fix the wrong frame pointer(setup_return calculate the offset > of fp through ilp32_sigframe instead of sigfreame), the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func1 () at test_force3.c:28 > #3 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > I am not sure there is still some issue in kernel. But it seem that the gdb of ilp32 > does not work correctly when unwind without framepointer. > > The test code is: > > #include > #include > #include > #include > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > > void func2() > { > *(int *)0 = 0x0; > } > > void func1() > { > func2(); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(); > return 0; > } > > > The full patch is as follows: > > From 7e364a765097f57aed2d73f94c1688c2e7343e79 Mon Sep 17 00:00:00 2001 > From: Bamvor Jian Zhang > Date: Sat, 4 Jun 2016 14:30:05 +0800 > Subject: [PATCH] arm64: ilp32: fix for wrong fp offset when calculate the > new fp > > ILP32 define its own sigframe(ilp32_sigframe) because of the > difference uc_context. setup_return do not use ilp32 specific > sigframe to calculate the new offset of fp which lead to wrong > fp in signal handler. At this circumstance, gdb backtrace will miss > one item: > (gdb) where > > It should be: > (gdb) where > > The test code is as follows: > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > void func2(int num) > { > printf("%s: %d\n", __FUNCTION__, num); > *(int *)0 = 0x0; > func2(num-1); > } > > void func1(int num) > { > printf("%s\n", __FUNCTION__); > func2(num - 1); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(argc); > return 0; > } > > This patch fix this by passing the correct offset of fp to > setup_return. > Test pass on both ILP32 and LP64 in aarch64 EE. > > Signed-off-by: Bamvor Jian Zhang > --- > arch/arm64/include/asm/signal_common.h | 3 ++- > arch/arm64/kernel/signal.c | 9 +++++---- > arch/arm64/kernel/signal_ilp32.c | 4 ++-- > 3 files changed, 9 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/include/asm/signal_common.h b/arch/arm64/include/asm/signal_common.h > index de93c71..a5d7b63 100644 > --- a/arch/arm64/include/asm/signal_common.h > +++ b/arch/arm64/include/asm/signal_common.h > @@ -29,6 +29,7 @@ int setup_sigcontex(struct sigcontext __user *uc_mcontext, > struct pt_regs *regs); > int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sf); > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig); > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig); > > #endif /* __ASM_SIGNAL_COMMON_H */ > diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c > index 038bebe..e66a6e9 100644 > --- a/arch/arm64/kernel/signal.c > +++ b/arch/arm64/kernel/signal.c > @@ -256,14 +256,14 @@ static struct rt_sigframe __user *get_sigframe(struct ksignal *ksig, > } > > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig) > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig) > { > __sigrestore_t sigtramp; > > regs->regs[0] = usig; > regs->sp = (unsigned long)frame; > - regs->regs[29] = regs->sp + sigframe_off + > - offsetof(struct sigframe, fp); > + regs->regs[29] = regs->sp + sigframe_off + fp_off; > regs->pc = (unsigned long)ka->sa.sa_handler; > > if (ka->sa.sa_flags & SA_RESTORER) > @@ -294,7 +294,8 @@ static int setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set, > err |= setup_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct rt_sigframe, sig), usig); > + offsetof(struct rt_sigframe, sig), > + offsetof(struct sigframe, fp), usig); > if (ksig->ka.sa.sa_flags & SA_SIGINFO) { > err |= copy_siginfo_to_user(&frame->info, &ksig->info); > regs->regs[1] = (unsigned long)&frame->info; > diff --git a/arch/arm64/kernel/signal_ilp32.c b/arch/arm64/kernel/signal_ilp32.c > index a8ea73e..9030f14 100644 > --- a/arch/arm64/kernel/signal_ilp32.c > +++ b/arch/arm64/kernel/signal_ilp32.c > @@ -147,7 +147,6 @@ static struct ilp32_rt_sigframe __user *ilp32_get_sigframe(struct ksignal *ksig, > struct ilp32_rt_sigframe __user *frame; > > sp = sp_top = sigsp(regs->sp, ksig); > - > sp = (sp - sizeof(struct ilp32_rt_sigframe)) & ~15; > frame = (struct ilp32_rt_sigframe __user *)sp; > > @@ -183,7 +182,8 @@ int ilp32_setup_rt_frame(int usig, struct ksignal *ksig, > err |= setup_ilp32_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct ilp32_rt_sigframe, sig), usig); > + offsetof(struct ilp32_rt_sigframe, sig), > + offsetof(struct ilp32_sigframe, fp), usig); > regs->regs[1] = (unsigned long)&frame->info; > regs->regs[2] = (unsigned long)&frame->sig.uc; > } From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zhangjian (Bamvor)" Subject: Re: [PATCH 21/23] arm64: ilp32: introduce ilp32-specific handlers for sigframe and ucontext Date: Sun, 12 Jun 2016 20:34:39 +0800 Message-ID: <575D56DF.8080203@huawei.com> References: <1464048292-30136-1-git-send-email-ynorov@caviumnetworks.com> <1464048292-30136-22-git-send-email-ynorov@caviumnetworks.com> <5752BCC8.7080205@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5752BCC8.7080205@huawei.com> Sender: linux-doc-owner@vger.kernel.org List-Archive: List-Post: To: Yury Norov , arnd@arndb.de, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, libc-alpha@sourceware.org Cc: schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, pinskia@gmail.com, broonie@kernel.org, joseph@codesourcery.com, christoph.muellner@theobroma-systems.com, szabolcs.nagy@arm.com, klimov.linux@gmail.com, Nathan_Lynch@mentor.com, agraf@suse.de, Prasun.Kapoor@caviumnetworks.com, kilobyte@angband.pl, geert@linux-m68k.org, philipp.tomsich@theobroma-systems.com, Andrew Pinski , Andrew Pinski , Hanjun Guo , "Zhangjian (Bamvor)" List-ID: ping On 2016/6/4 19:34, Zhangjian (Bamvor) wrote: > Hi, > > I found an issue of unwind with the following code. The correct backtrace > should be: > (gdb) where > #0 0x004004d0 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func2 (num=0) at test_force3.c:22 > #3 0x00400540 in func1 (num=1) at test_force3.c:28 > #4 0x00400574 in main (argc=1, argv=0xffd7bc04) at test_force3.c:33 > > Without my patch, the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > With my patch which fix the wrong frame pointer(setup_return calculate the offset > of fp through ilp32_sigframe instead of sigfreame), the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func1 () at test_force3.c:28 > #3 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > I am not sure there is still some issue in kernel. But it seem that the gdb of ilp32 > does not work correctly when unwind without framepointer. > > The test code is: > > #include > #include > #include > #include > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > > void func2() > { > *(int *)0 = 0x0; > } > > void func1() > { > func2(); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(); > return 0; > } > > > The full patch is as follows: > > From 7e364a765097f57aed2d73f94c1688c2e7343e79 Mon Sep 17 00:00:00 2001 > From: Bamvor Jian Zhang > Date: Sat, 4 Jun 2016 14:30:05 +0800 > Subject: [PATCH] arm64: ilp32: fix for wrong fp offset when calculate the > new fp > > ILP32 define its own sigframe(ilp32_sigframe) because of the > difference uc_context. setup_return do not use ilp32 specific > sigframe to calculate the new offset of fp which lead to wrong > fp in signal handler. At this circumstance, gdb backtrace will miss > one item: > (gdb) where > > It should be: > (gdb) where > > The test code is as follows: > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > void func2(int num) > { > printf("%s: %d\n", __FUNCTION__, num); > *(int *)0 = 0x0; > func2(num-1); > } > > void func1(int num) > { > printf("%s\n", __FUNCTION__); > func2(num - 1); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(argc); > return 0; > } > > This patch fix this by passing the correct offset of fp to > setup_return. > Test pass on both ILP32 and LP64 in aarch64 EE. > > Signed-off-by: Bamvor Jian Zhang > --- > arch/arm64/include/asm/signal_common.h | 3 ++- > arch/arm64/kernel/signal.c | 9 +++++---- > arch/arm64/kernel/signal_ilp32.c | 4 ++-- > 3 files changed, 9 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/include/asm/signal_common.h b/arch/arm64/include/asm/signal_common.h > index de93c71..a5d7b63 100644 > --- a/arch/arm64/include/asm/signal_common.h > +++ b/arch/arm64/include/asm/signal_common.h > @@ -29,6 +29,7 @@ int setup_sigcontex(struct sigcontext __user *uc_mcontext, > struct pt_regs *regs); > int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sf); > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig); > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig); > > #endif /* __ASM_SIGNAL_COMMON_H */ > diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c > index 038bebe..e66a6e9 100644 > --- a/arch/arm64/kernel/signal.c > +++ b/arch/arm64/kernel/signal.c > @@ -256,14 +256,14 @@ static struct rt_sigframe __user *get_sigframe(struct ksignal *ksig, > } > > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig) > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig) > { > __sigrestore_t sigtramp; > > regs->regs[0] = usig; > regs->sp = (unsigned long)frame; > - regs->regs[29] = regs->sp + sigframe_off + > - offsetof(struct sigframe, fp); > + regs->regs[29] = regs->sp + sigframe_off + fp_off; > regs->pc = (unsigned long)ka->sa.sa_handler; > > if (ka->sa.sa_flags & SA_RESTORER) > @@ -294,7 +294,8 @@ static int setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set, > err |= setup_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct rt_sigframe, sig), usig); > + offsetof(struct rt_sigframe, sig), > + offsetof(struct sigframe, fp), usig); > if (ksig->ka.sa.sa_flags & SA_SIGINFO) { > err |= copy_siginfo_to_user(&frame->info, &ksig->info); > regs->regs[1] = (unsigned long)&frame->info; > diff --git a/arch/arm64/kernel/signal_ilp32.c b/arch/arm64/kernel/signal_ilp32.c > index a8ea73e..9030f14 100644 > --- a/arch/arm64/kernel/signal_ilp32.c > +++ b/arch/arm64/kernel/signal_ilp32.c > @@ -147,7 +147,6 @@ static struct ilp32_rt_sigframe __user *ilp32_get_sigframe(struct ksignal *ksig, > struct ilp32_rt_sigframe __user *frame; > > sp = sp_top = sigsp(regs->sp, ksig); > - > sp = (sp - sizeof(struct ilp32_rt_sigframe)) & ~15; > frame = (struct ilp32_rt_sigframe __user *)sp; > > @@ -183,7 +182,8 @@ int ilp32_setup_rt_frame(int usig, struct ksignal *ksig, > err |= setup_ilp32_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct ilp32_rt_sigframe, sig), usig); > + offsetof(struct ilp32_rt_sigframe, sig), > + offsetof(struct ilp32_sigframe, fp), usig); > regs->regs[1] = (unsigned long)&frame->info; > regs->regs[2] = (unsigned long)&frame->sig.uc; > } From mboxrd@z Thu Jan 1 00:00:00 1970 From: bamvor.zhangjian@huawei.com (Zhangjian (Bamvor)) Date: Sun, 12 Jun 2016 20:34:39 +0800 Subject: [PATCH 21/23] arm64: ilp32: introduce ilp32-specific handlers for sigframe and ucontext In-Reply-To: <5752BCC8.7080205@huawei.com> References: <1464048292-30136-1-git-send-email-ynorov@caviumnetworks.com> <1464048292-30136-22-git-send-email-ynorov@caviumnetworks.com> <5752BCC8.7080205@huawei.com> Message-ID: <575D56DF.8080203@huawei.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org ping On 2016/6/4 19:34, Zhangjian (Bamvor) wrote: > Hi, > > I found an issue of unwind with the following code. The correct backtrace > should be: > (gdb) where > #0 0x004004d0 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func2 (num=0) at test_force3.c:22 > #3 0x00400540 in func1 (num=1) at test_force3.c:28 > #4 0x00400574 in main (argc=1, argv=0xffd7bc04) at test_force3.c:33 > > Without my patch, the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > With my patch which fix the wrong frame pointer(setup_return calculate the offset > of fp through ilp32_sigframe instead of sigfreame), the backtrace is: > (gdb) where > #0 0x00400490 in my_sig (sig=11) at test_force3.c:16 > #1 > #2 func1 () at test_force3.c:28 > #3 0x004004e4 in main (argc=1, argv=0xffe6f8f4) at test_force3.c:33 > > I am not sure there is still some issue in kernel. But it seem that the gdb of ilp32 > does not work correctly when unwind without framepointer. > > The test code is: > > #include > #include > #include > #include > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > > void func2() > { > *(int *)0 = 0x0; > } > > void func1() > { > func2(); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(); > return 0; > } > > > The full patch is as follows: > > From 7e364a765097f57aed2d73f94c1688c2e7343e79 Mon Sep 17 00:00:00 2001 > From: Bamvor Jian Zhang > Date: Sat, 4 Jun 2016 14:30:05 +0800 > Subject: [PATCH] arm64: ilp32: fix for wrong fp offset when calculate the > new fp > > ILP32 define its own sigframe(ilp32_sigframe) because of the > difference uc_context. setup_return do not use ilp32 specific > sigframe to calculate the new offset of fp which lead to wrong > fp in signal handler. At this circumstance, gdb backtrace will miss > one item: > (gdb) where > > It should be: > (gdb) where > > The test code is as follows: > > void my_sig(int sig) > { > printf("sig=%d\n", sig); > *(int *)0 = 0x0; > } > > void func2(int num) > { > printf("%s: %d\n", __FUNCTION__, num); > *(int *)0 = 0x0; > func2(num-1); > } > > void func1(int num) > { > printf("%s\n", __FUNCTION__); > func2(num - 1); > } > > int main(int argc, char **argv) > { > signal(11, my_sig); > func1(argc); > return 0; > } > > This patch fix this by passing the correct offset of fp to > setup_return. > Test pass on both ILP32 and LP64 in aarch64 EE. > > Signed-off-by: Bamvor Jian Zhang > --- > arch/arm64/include/asm/signal_common.h | 3 ++- > arch/arm64/kernel/signal.c | 9 +++++---- > arch/arm64/kernel/signal_ilp32.c | 4 ++-- > 3 files changed, 9 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/include/asm/signal_common.h b/arch/arm64/include/asm/signal_common.h > index de93c71..a5d7b63 100644 > --- a/arch/arm64/include/asm/signal_common.h > +++ b/arch/arm64/include/asm/signal_common.h > @@ -29,6 +29,7 @@ int setup_sigcontex(struct sigcontext __user *uc_mcontext, > struct pt_regs *regs); > int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sf); > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig); > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig); > > #endif /* __ASM_SIGNAL_COMMON_H */ > diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c > index 038bebe..e66a6e9 100644 > --- a/arch/arm64/kernel/signal.c > +++ b/arch/arm64/kernel/signal.c > @@ -256,14 +256,14 @@ static struct rt_sigframe __user *get_sigframe(struct ksignal *ksig, > } > > void setup_return(struct pt_regs *regs, struct k_sigaction *ka, > - void __user *frame, off_t sigframe_off, int usig) > + void __user *frame, off_t sigframe_off, off_t fp_off, > + int usig) > { > __sigrestore_t sigtramp; > > regs->regs[0] = usig; > regs->sp = (unsigned long)frame; > - regs->regs[29] = regs->sp + sigframe_off + > - offsetof(struct sigframe, fp); > + regs->regs[29] = regs->sp + sigframe_off + fp_off; > regs->pc = (unsigned long)ka->sa.sa_handler; > > if (ka->sa.sa_flags & SA_RESTORER) > @@ -294,7 +294,8 @@ static int setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set, > err |= setup_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct rt_sigframe, sig), usig); > + offsetof(struct rt_sigframe, sig), > + offsetof(struct sigframe, fp), usig); > if (ksig->ka.sa.sa_flags & SA_SIGINFO) { > err |= copy_siginfo_to_user(&frame->info, &ksig->info); > regs->regs[1] = (unsigned long)&frame->info; > diff --git a/arch/arm64/kernel/signal_ilp32.c b/arch/arm64/kernel/signal_ilp32.c > index a8ea73e..9030f14 100644 > --- a/arch/arm64/kernel/signal_ilp32.c > +++ b/arch/arm64/kernel/signal_ilp32.c > @@ -147,7 +147,6 @@ static struct ilp32_rt_sigframe __user *ilp32_get_sigframe(struct ksignal *ksig, > struct ilp32_rt_sigframe __user *frame; > > sp = sp_top = sigsp(regs->sp, ksig); > - > sp = (sp - sizeof(struct ilp32_rt_sigframe)) & ~15; > frame = (struct ilp32_rt_sigframe __user *)sp; > > @@ -183,7 +182,8 @@ int ilp32_setup_rt_frame(int usig, struct ksignal *ksig, > err |= setup_ilp32_sigframe(&frame->sig, regs, set); > if (err == 0) { > setup_return(regs, &ksig->ka, frame, > - offsetof(struct ilp32_rt_sigframe, sig), usig); > + offsetof(struct ilp32_rt_sigframe, sig), > + offsetof(struct ilp32_sigframe, fp), usig); > regs->regs[1] = (unsigned long)&frame->info; > regs->regs[2] = (unsigned long)&frame->sig.uc; > }