From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: In-Reply-To: <20070323120619.GA7472@localhost.localdomain> References: <1174544624.10836.24.camel@localhost.localdomain> <94d8e19d4b061504fcfd08d1ab70cc78@kernel.crashing.org> <20070323120619.GA7472@localhost.localdomain> Mime-Version: 1.0 (Apple Message framework v623) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: From: Segher Boessenkool Subject: Re: [PATCH] force -mno-string option on cell Date: Fri, 23 Mar 2007 13:56:51 +0100 To: Akinobu Mita Cc: linuxppc-dev list , Paul Mackerras , cbe-oss-dev@ozlabs.org, Arnd Bergmann List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > GCC may generate inline copy loop to handle memcpy() function > instead of kernel defined memcpy() with -mstring or -Os. > But this inlined version of memcpy() caused an alignment interrupt > when copying from SPU local store on PS3. > (http://ozlabs.org/pipermail/cbe-oss-dev/2007-March/001348.html) > > This patch deletes -mstring option on all powerpc and force -mno-string > option on Cell. Please split into two patches, the first half (deleting -mstring) we can all agree on and "the other half". What your patch does is setting -mno-string for all files if your kernel is configured to support Cell. It would be better to set this option (and all other options needed, -mno-multiple and -mno-algebraic come to mind, and that last compiler option doesn't even exist yet) unconditionally on the few Cell-specific files that are affected, not on the whole kernel: CFLAGS_whatever.o := -msome-flags It would be even better to not lie to the compiler by telling it it can use the LS area as normal memory, since evidently it cannot :-) Segher