From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCHV5 3/3] x86, ras: Add __mcsafe_copy() function to recover from machine checks Date: Sun, 27 Dec 2015 11:09:19 +0100 Message-ID: <20151227100919.GA19398@nazgul.tnic> References: <20151224214632.GF4128@pd.tnic> <20151225114937.GA862@pd.tnic> <5FBC1CF1-095B-466D-85D6-832FBFA98364@intel.com> <20151226103252.GA21988@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Tony Luck , Andy Lutomirski Cc: linux-nvdimm , X86 ML , "elliott@hpe.com" , "linux-mm@kvack.org" , Andrew Morton , "Williams, Dan J" , Ingo Molnar , "linux-kernel@vger.kernel.org" List-Id: linux-mm.kvack.org On Sat, Dec 26, 2015 at 10:57:26PM -0800, Tony Luck wrote: > ... will get the right value. Maybe this would still work out > if the fixup is a 31-bit value plus a flag, but the external > tool thinks it is a 32-bit value? I'd have to ponder that. I still fail to see why do we need to make it so complicated and can't do something like: fixup_exception: ... #ifdef CONFIG_MCE_KERNEL_RECOVERY if (regs->ip >= (unsigned long)__mcsafe_copy && regs->ip <= (unsigned long)__mcsafe_copy_end) run_special_handler(); #endif and that special handler does all the stuff we want. And we pass X86_TRAP* etc through fixup_exception along with whatever else we need from the trap handler... Hmmm? -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. --