From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 10 May 2019 14:07:09 +0900 From: Sergey Senozhatsky Subject: Re: [PATCH] vsprintf: Do not break early boot with probing addresses Message-ID: <20190510050709.GA1831@jagdpanzerIV> References: <20190509121923.8339-1-pmladek@suse.com> <20190510043200.GC15652@jagdpanzerIV> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-arch-owner@vger.kernel.org Message-ID: <20190510050709.ugUsmdWEg2-_zeuhzXY9dG3VOFvC7DcdjoUsQ1gSOxk@z> List-Archive: List-Post: To: Linus Torvalds Cc: Sergey Senozhatsky , Petr Mladek , Andy Shevchenko , Rasmus Villemoes , "Tobin C . Harding" , Michal Hocko , Sergey Senozhatsky , Steven Rostedt , linux-kernel@vger.kernel.org, Michael Ellerman , linuxppc-dev@lists.ozlabs.org, Russell Currey , Christophe Leroy , Stephen Rothwell , Heiko Carstens , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Martin Schwidefsky List-ID: On (05/09/19 21:47), Linus Torvalds wrote: > [ Sorry about html and mobile crud, I'm not at the computer right now ] > How about we just undo the whole misguided probe_kernel_address() thing? But the problem will remain - %pS/%pF on PPC (and some other arch-s) do dereference_function_descriptor(), which calls probe_kernel_address(). So if probe_kernel_address() starts to dump_stack(), then we are heading towards stack overflow. Unless I'm totally missing something. -ss