From mboxrd@z Thu Jan 1 00:00:00 1970 From: kristof@sigsegv.be (Kristof Provost) Date: Wed, 14 May 2014 14:14:06 +0200 Subject: hook SIGSEGV In-Reply-To: References: Message-ID: <20140514121405.GW2613@vega.codepro.be> To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org On 2014-05-10 21:46:01 (+0800), net.study.sea at gmail.com wrote: > I want to know is it possible to hook SIGSEGV to restart the > thread which the signal is sent to,without restart the whole > process? And record the place where has caused this signal? > Yes, as others have already pointed out, you can hook SIGSEGV like any other signal. You're not going to be able to save the process any more, but you can still collect some useful information. I've found it very useful to have a SIGSEGV (and SIGPIPE, SIGABRT, SIGFPE, SIGILL) handler which logs a backtrace (look at 'man backtrace') to syslog. Very useful for debugging on targets where core dumps are impractical. Others have also pointed out that it might no longer be safe to call printf() or malloc() there. That's true, but usually it's OK, and if it turns out that it wasn't ... Well, you were crashing anyway. Regards, Kristof