Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: Question: livepatch failed for new fork() task stack unreliable
To:     Josh Poimboeuf <jpoimboe@redhat.com>
CC:     <huawei.libin@huawei.com>, <xiexiuqi@huawei.com>,
        <cj.chengjian@huawei.com>, <mingo@redhat.com>, <x86@kernel.org>,
        <linux-kernel@vger.kernel.org>, <live-patching@vger.kernel.org>,
        <mbenes@suse.cz>, <devel@etsukata.com>, <viro@zeniv.linux.org.uk>,
        <esyr@redhat.com>
References: <20200529174433.wpkknhypx2bmjika@treble>
 <a9ed9157-f3cf-7d2c-7a8e-56150a2a114e@huawei.com>
 <20200601180538.o5agg5trbdssqken@treble>
 <a5e0f476-02b5-cc44-8d4e-d33ff2138143@huawei.com>
 <20200602131450.oydrydelpdaval4h@treble>
 <1353648b-f3f7-5b8d-f0bb-28bdb1a66f0f@huawei.com>
 <20200603153358.2ezz2pgxxxld7mj7@treble>
 <2225bc83-95f2-bf3d-7651-fdd10a3ddd00@huawei.com>
 <20200604024051.6ovbr6tbrowwg6jr@treble>
 <c3a81224-bea1-116b-7528-f03f90be5264@huawei.com>
 <20200605015142.w65uu5wxfmrun2ro@treble>
From:   "Wangshaobo (bobo)" <bobo.shaobowang@huawei.com>
Message-ID: <e914bcd6-009c-0a89-bc59-b9a87a9c552d@huawei.com>
Date:   Tue, 30 Jun 2020 21:04:12 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101
 Thunderbird/68.1.0
MIME-Version: 1.0
In-Reply-To: <20200605015142.w65uu5wxfmrun2ro@treble>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


在 2020/6/5 9:51, Josh Poimboeuf 写道:
> On Fri, Jun 05, 2020 at 09:26:42AM +0800, Wangshaobo (bobo) wrote:
>>>> So, I want to ask is there any side effects if i modify like this ? this
>>>> modification is based on
>>>>
>>>> your fix. It looks like ok with proper test.
>>>>
>>>> diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
>>>> index e9cc182aa97e..ecce5051e8fd 100644
>>>> --- a/arch/x86/kernel/unwind_orc.c
>>>> +++ b/arch/x86/kernel/unwind_orc.c
>>>> @@ -620,6 +620,7 @@ void __unwind_start(struct unwind_state *state, struct
>>>> task_struct *task,
>>>>                   state->sp = task->thread.sp;
>>>>                   state->bp = READ_ONCE_NOCHECK(frame->bp);
>>>>                   state->ip = READ_ONCE_NOCHECK(frame->ret_addr);
>>>> +              state->signal = ((void *)state->ip == ret_from_fork);
>>>>           }
>>>>
>>>> diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
>>>> index 7f969b2d240f..d7396431261a 100644
>>>> --- a/arch/x86/kernel/unwind_orc.c
>>>> +++ b/arch/x86/kernel/unwind_orc.c
>>>> @@ -540,7 +540,7 @@ bool unwind_next_frame(struct unwind_state *state)
>>>>            state->sp = sp;
>>>>            state->regs = NULL;
>>>>            state->prev_regs = NULL;
>>>> -        state->signal = ((void *)state->ip == ret_from_fork);
>>>> +        state->signal = false;
>>>>            break;
>>> Yes that's correct.
>> Hi, josh
>>
>> Could i ask when are you free to send the patch, all the tests are passed
>> by.
> I want to run some regression tests, so it will probably be next week.

Hi, josh

did you send this patch, I haven't received it up to now, so i ask u to 
confirm again.

thanks,

Wang ShaoBo