[PATCH 1/1] mm: call force_sig_info before prints

Wed Dec 21 01:21:59 PST 2016

This is unreadable.  Sorry.

On Wed, Dec 21, 2016 at 05:59:11AM +0000, AMIT NAGAL wrote:
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> <P>Hello,</P><PRE>On Mon, Dec 19, 2016 at 04:07:12PM +0530, Maninder Singh wrote:
> >> prints can delay queuing of signal, so better to print
> >>after force_sig_info.
> >> 
> >> Let's say process generated SIGSEGV , and some other thread sends
> >> SIGKILL to crashing process and it gets queued before SIGSEGV becuase
> >> of little delay due to prints so in this case coredump might not generate.
> 
> > In any case, that's going to be a race - you can't predict exactly when
> > the "other thread" will send the SIGKILL in relation to the SIGSEGV.
> 
> > So, I don't see the point of this change.</PRE><PRE>Actually SIGSEGV queueing gets delayed in __do_user_fault as logs are printed first(show_pte , show_regs).</PRE><PRE>meanwhile if SIGKILL gets queued , SIGSEGV wont be serviced first and coredump will be skipped . </PRE><PRE>so our intention is to queue the SIGSEGV as early as possible . so that the probability of race between</PRE><PRE>SIGKILL and SIGSEGV can be minimized .</PRE><PRE>Amit</PRE><PRE> </PRE><table id=bannersignimg><tr><td><div id="cafe-note-contents" style="margin:10px;font-family:Arial;font-size:10pt;"><p> </p></div></td></tr></table><table id=confidentialsignimg><tr><td><div id="cafe-note-contents" style="margin:10px;font-family:Arial;font-size:10pt;"><p><img unselectable="on" data-cui-image="true" style="display: inline-block; border: 0px solid; width: 520px; height: 144px;" src="cid:cafe_image_0 at s-core.co.kr"><br></p></div></td></tr></table></BODY></HTML><img src='http://ext.samsung.net/mail/ext/v1/external/status/update?userid=amit.nagal&do=bWFpbElEPTIwMTYxMjIxMDU1OTExZXBjbXM1cDExNDZjZWU5MjEyY2MxN2ZhOGQ1YjE4YzQ5YTA4NWRlZiZyZWNpcGllbnRBZGRyZXNzPWxpbnV4QGFybWxpbnV4Lm9yZy51aw__' border=0 width=0 height=0 style='display:none'>

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