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Date: Thu, 07 Jun 2007 19:15:04 +0900
Message-ID: <87tztk9il3.wl%takeuchi_satoru@jp.fujitsu.com>
From: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
To: Roland McGrath <roland@redhat.com>
Cc: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>,
       Linux Kernel <linux-kernel@vger.kernel.org>,
       Linus Torvalds <torvalds@osdl.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Oleg Nesterov <oleg@tv-sign.ru>
Subject: Re: [BUG] 2.6.22-rc4: wait4() waiting for SIGSTOP may not return if the target process is ptraced
In-Reply-To: <20070607095432.559744D0597@magilla.localdomain>
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Hi,

At Thu,  7 Jun 2007 02:54:32 -0700 (PDT),
Roland McGrath wrote:
> 
> The bug is in strace (and is being fixed).  It needs to use tgkill instead
> of kill to send that SIGSTOP to the right thread only.  

You mean kill() to specifig thread is fundamentally wrong? If so, current
kill() is wrong because it can receive pid of non main thread.

Thanks,

Satoru