From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Subject: Re: [PATCH -tip v14 01/12] x86: instruction decoder API Date: Thu, 20 Aug 2009 15:01:25 -0400 Message-ID: <4A8D9D85.50809@redhat.com> References: <20090813203403.31965.20973.stgit@localhost.localdomain> <20090813203413.31965.49709.stgit@localhost.localdomain> <20090819234227.GJ4972@nowhere> <20090820002113.GK4972@nowhere> <4A8D65CC.8030205@redhat.com> <20090820152549.GD6389@nowhere> <4A8D76C5.9060008@redhat.com> <20090820180737.GA6229@nowhere> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Cc: Ingo Molnar , Steven Rostedt , lkml , systemtap , kvm , DLE , Jim Keniston , "H. Peter Anvin" , Ananth N Mavinakayanahalli , Avi Kivity , Andi Kleen , Christoph Hellwig , "Frank Ch. Eigler" , Jason Baron , "K.Prasad" , Lai Jiangshan , Li Zefan , =?UTF-8?B?UHJ6ZW15c8WCYXdQYXdlxYJjenlr?= , Roland McGrath , Sam Ravnborg , Srikar Dronamraju Return-path: In-Reply-To: <20090820180737.GA6229@nowhere> List-Unsubscribe: List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org List-Id: kvm.vger.kernel.org Frederic Weisbecker wrote: > On Thu, Aug 20, 2009 at 12:16:05PM -0400, Masami Hiramatsu wrote: >> Frederic Weisbecker wrote: >>> On Thu, Aug 20, 2009 at 11:03:40AM -0400, Masami Hiramatsu wrote: >>>> Frederic Weisbecker wrote: >>>>> On Thu, Aug 20, 2009 at 01:42:31AM +0200, Frederic Weisbecker wrote: >>>>>> On Thu, Aug 13, 2009 at 04:34:13PM -0400, Masami Hiramatsu wrote: >>>>>>> Add x86 instruction decoder to arch-specific libraries. This decoder >>>>>>> can decode x86 instructions used in kernel into prefix, opcode, modrm, >>>>>>> sib, displacement and immediates. This can also show the length of >>>>>>> instructions. >>>>>>> >>>>>>> This version introduces instruction attributes for decoding instructions. >>>>>>> The instruction attribute tables are generated from the opcode map file >>>>>>> (x86-opcode-map.txt) by the generator script(gen-insn-attr-x86.awk). >>>>>>> >>>>>>> Currently, the opcode maps are based on opcode maps in Intel(R) 64 and >>>>>>> IA-32 Architectures Software Developers Manual Vol.2: Appendix.A, >>>>>>> and consist of below two types of opcode tables. >>>>>>> >>>>>>> 1-byte/2-bytes/3-bytes opcodes, which has 256 elements, are >>>>>>> written as below; >>>>>>> >>>>>>> Table: table-name >>>>>>> Referrer: escaped-name >>>>>>> opcode: mnemonic|GrpXXX [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] >>>>>>> (or) >>>>>>> opcode: escape # escaped-name >>>>>>> EndTable >>>>>>> >>>>>>> Group opcodes, which has 8 elements, are written as below; >>>>>>> >>>>>>> GrpTable: GrpXXX >>>>>>> reg: mnemonic [operand1[,operand2...]] [(extra1)[,(extra2)...] [| 2nd-mnemonic ...] >>>>>>> EndTable >>>>>>> >>>>>>> These opcode maps include a few SSE and FP opcodes (for setup), because >>>>>>> those opcodes are used in the kernel. >>>>>>> >>>>>> >>>>>> >>>>>> I'm getting the following build error on an old K7 box: >>>>>> >>>>>> arch/x86/lib/inat.c: In function ‘inat_get_opcode_attribute’: >>>>>> arch/x86/lib/inat.c:29: erreur: ‘inat_primary_table’ undeclared (first use in this function) >>>>>> arch/x86/lib/inat.c:29: erreur: (Each undeclared identifier is reported only once >>>>>> arch/x86/lib/inat.c:29: erreur: for each function it appears in.) >>>>>> >>>>>> >>>>>> I've attached my config. I haven't such problem on a dual x86-64 box. >>>>> >>>>> >>>>> Actually I have the same problem in x86-64 >>>>> The content of my arch/x86/lib/inat-tables.c: >>>>> >>>>> /* x86 opcode map generated from x86-opcode-map.txt */ >>>>> /* Do not change this code. */ >>>>> /* Table: one byte opcode */ >>>>> /* Escape opcode map array */ >>>>> const insn_attr_t const *inat_escape_tables[INAT_ESC_MAX + 1][INAT_LPREFIX_MAX + 1] = { >>>>> }; >>>>> >>>>> /* Group opcode map array */ >>>>> const insn_attr_t const *inat_group_tables[INAT_GRP_MAX + 1][INAT_LPREFIX_MAX + 1] = { >>>>> }; >>>>> >>>>> >>>>> I guess there is a problem with the generation of this file. >>>> >>>> Aah, you may use mawk on Ubuntu 9.04, right? >>>> If so, unfortunately, mawk is still under development. >>>> >>>> http://invisible-island.net/mawk/CHANGES >>> >>> >>> >>> Aargh... >>> >>> >>>>> 20090727 >>>>> add check/fix to prevent gsub from recurring to modify on a substring >>>>> of the current line when the regular expression is anchored to the >>>>> beginning of the line; fixes gawk's anchgsub testcase. >>>>> >>>>> add check for implicit concatenation mistaken for exponent; fixes >>>>> gawk's hex testcase. >>>>> >>>>> add character-classes to built-in regular expressions. >>>> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >>>> Look, this means we can't use char-class expressions like >>>> [:lower:] until this version... >>>> >>>> And I've found another bug in mawk-1.3.3-20090728(the latest one). >>>> it almost works, but; >>>> >>>> $ mawk 'BEGIN {printf("0x%x\n", 0)}' >>>> 0x1 >>> >>> >>> Ouch, indeed. >>> >>> >>> >>>> $ gawk 'BEGIN {printf("0x%x\n", 0)}' >>>> 0x0 >>>> >>>> This bug skips an array element index 0x0 in inat-tables.c :( >>>> >>>> So, I recommend you to install gawk instead mawk until that >>>> supports all posix-awk features, since I don't think it is >>>> good idea to avoid all those bugs which depends on >>>> implementation (not specification). >>>> >>>> >>>> Thank you, >>> >>> >>> >>> Yeah, indeed. May be add a warning (or build error) in case the user uses >>> mawk? >> >> Hmm, it is possible that mawk will fix those bugs and catch up soon, >> so, I think checking mawk is not a good idea. >> (and since there will be other awk implementations, it's not fair.) >> >> I think what all I can do now is reporting bugs to >> mawk and ubuntu people.:-) > > > > Yeah, but without your tip I couldn't be able to find the origin > before some time. > And the kernel couldn't build anyway. > > At least we should do something with this version of mawk. Hm, indeed. Maybe, we can run additional sanity check script before using awk, like this; --- res=`echo a | $AWK '/[[:lower:]]+/{print "OK"}'` [ "$res" != "OK" ] && exit 1 res=`$AWK 'BEGIN {printf("%x", 0)}'` [ "$res" != "0" ] && exit 1 exit 0 --- Thanks, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@redhat.com