i686 quirk for AMD Geode
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From: Matteo Croce on 6 Nov 2009 10:00 On Sat, Oct 3, 2009 at 8:21 AM, Ingo Molnar <mingo(a)elte.hu> wrote: > > * Matteo Croce <technoboy85(a)gmail.com> wrote: > >> Hi, >> >> the AMD GEode LX has an x86 id of 5 (i586) tought it's technically an i686: >> >> root(a)alix:/usr/src# cat /proc/cpuinfo >> processor � � � : 0 >> vendor_id � � � : AuthenticAMD >> cpu family � � �: 5 >> model � � � � � : 10 >> model name � � �: Geode(TM) Integrated Processor by AMD PCS >> stepping � � � �: 2 >> cpu MHz � � � � : 498.060 >> cache size � � �: 128 KB >> fdiv_bug � � � �: no >> hlt_bug � � � � : no >> f00f_bug � � � �: no >> coma_bug � � � �: no >> fpu � � � � � � : yes >> fpu_exception � : yes >> cpuid level � � : 1 >> wp � � � � � � �: yes >> flags � � � � � : fpu de pse tsc msr cx8 sep pge cmov clflush mmx >> mmxext 3dnowext 3dnow >> bogomips � � � �: 996.12 >> clflush size � �: 32 >> cache_alignment : 32 >> address sizes � : 32 bits physical, 32 bits virtual >> power management: >> >> indeed it has mmx, mmxext and cmov. >> So I added the quirk below and I can confirm that the system is running fine. >> I did an x264 encode to trigger any SIGILL due to missing opcodes, but >> it worked. >> >> I also did this simple test which gives a ~2.5x speed boost: >> http://pastebin.ca/1590089 >> >> I wish some feedback from someone, I really dunno why AMD set the >> cpuid value to 5 >> >> --- a/arch/x86/kernel/cpu/bugs.c � � �2009-10-03 03:43:02.399323313 +0200 >> +++ b/arch/x86/kernel/cpu/bugs.c � � �2009-10-03 03:54:22.582205090 +0200 >> @@ -151,6 +151,12 @@ >> �#endif >> �} >> >> +static void __init check_geode_i586(void) >> +{ >> + � � if(boot_cpu_data.x86_vendor == X86_VENDOR_AMD && >> + � � � �boot_cpu_data.x86_model == 10 && boot_cpu_data.x86 == 5) >> + � � � � � � boot_cpu_data.x86 = 6; >> +} >> >> �void __init check_bugs(void) >> �{ >> @@ -163,6 +169,7 @@ >> � � � check_fpu(); >> � � � check_hlt(); >> � � � check_popad(); >> + � � check_geode_i586(); >> � � � init_utsname()->machine[1] = >> � � � � � � � '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86); >> � � � alternative_instructions(); > > Looks good, but your signoff line is missing. > > � � � �Ingo > The AMD Geode LX has an x86 id of 5 (i586) tought it's technically an i686: root(a)alix:~# egrep '^(cpu family|model name|flags)' /proc/cpuinfo cpu family : 5 model name : Geode(TM) Integrated Processor by AMD PCS flags : fpu de pse tsc msr cx8 sep pge cmov clflush mmx mmxext 3dnowext 3dnow indeed it has MMX, MMXEXT and CMOV, just lacks the long NOP instruction (NOPL). This patch adds a quirck to promote the Geode to an i686 and emulates the NOPL in the do_invalid_op trap, so the userspace never notices. Emulating the NOPL has minimum performance loss, emulating a NOPL takes 0.5 usecs and they are rarely used in x86 Signed-off-by: Matteo Croce <technoboy85(a)gmail.com> --- a/arch/x86/kernel/Makefile 2009-11-06 15:06:52.246223989 +0100 +++ b/arch/x86/kernel/Makefile 2009-11-06 15:07:04.294054613 +0100 @@ -89,7 +89,7 @@ obj-$(CONFIG_HPET_TIMER) += hpet.o obj-$(CONFIG_K8_NB) += k8.o -obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o +obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o nopl_emu.o obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o --- a/arch/x86/kernel/cpu/amd.c 2009-11-06 15:06:52.254223805 +0100 +++ b/arch/x86/kernel/cpu/amd.c 2009-11-06 15:07:04.294054613 +0100 @@ -138,8 +138,10 @@ } if (c->x86_model == 10) { - /* AMD Geode LX is model 10 */ - /* placeholder for any needed mods */ + /* Geode only lacks the NOPL instruction to be i686, + but we can emulate it in the exception handler + and promote it to a class 6 cpu */ + boot_cpu_data.x86 = 6; return; } } --- a/arch/x86/kernel/entry_32.S 2009-11-06 15:06:52.258224172 +0100 +++ b/arch/x86/kernel/entry_32.S 2009-11-06 15:07:04.306230613 +0100 @@ -901,7 +901,11 @@ RING0_INT_FRAME pushl $0 CFI_ADJUST_CFA_OFFSET 4 +#ifdef CONFIG_MGEODE_LX + pushl $do_nopl_emu +#else pushl $do_invalid_op +#endif CFI_ADJUST_CFA_OFFSET 4 jmp error_code CFI_ENDPROC --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ b/arch/x86/kernel/nopl_emu.c 2009-11-06 15:07:33.537723795 +0100 @@ -0,0 +1,102 @@ +/* + * linux/arch/x86/kernel/nopl_emu.c + * + * Copyright (C) 2002 Willy Tarreau + * Copyright (C) 2009 Matteo Croce + */ + +#include <linux/sched.h> +#include <linux/linkage.h> +#include <linux/preempt.h> +#include <linux/types.h> + +void do_invalid_op(struct pt_regs *regs, long error_code); + +/* This code can be used to allow the AMD Geode to hopefully correctly execute + * some code which was originally compiled for an i686, by emulating NOPL, + * the only missing i686 instruction in the CPU + * + * Willy Tarreau <willy(a)meta-x.org> + * Matteo Croce <technoboy85(a)gmail.com> + */ + +static inline int do_1f(u8 *ip) +{ + int length = 3; + switch(*ip) { + case 0x84:if(!ip[5]) + length++; + else + return 0; + case 0x80:if(!ip[4] && !ip[3]) + length += 2; + else + return 0; + case 0x44:if(!ip[2]) + length++; + else + return 0; + case 0x40:if(!ip[1]) + length++; + else + return 0; + case 0x00:return length; + default: return 0; + } + return length; +} + +static inline int do_0f(u8 *ip) +{ + if(*ip == 0x1f) + return do_1f(ip + 1); + return 0; +} + +static inline int do_66(u8 *ip) +{ + if(*ip == 0x90) + return 2; + if(*ip == 0x0f) { + int res = do_0f(ip + 1); + if(res) + return res + 1; + else + return 0; + } + return 0; +} + +static inline int do_start(u8 *ip) +{ + if(*ip == 0x0f) + return do_0f(ip + 1); + if(*ip == 0x66) + return do_66(ip + 1); + return 0; +} + +/* [do_nopl_emu] is called by exception 6 after an invalid opcode has been + * encountered. It will try to emulate it by doing nothing, + * and will send a SIGILL or SIGSEGV to the process if not possible. + * the NOPL can have variable length opcodes: + +bytes number opcode + 2 66 90 + 3 0f 1f 00 + 4 0f 1f 40 00 + 5 0f 1f 44 00 00 + 6 66 0f 1f 44 00 00 + 7 0f 1f 80 00 00 00 00 + 8 0f 1f 84 00 00 00 00 00 + 9 66 0f 1f 84 00 00 00 00 00 +*/ +void do_nopl_emu(struct pt_regs *regs, long error_code) +{ + int res = do_start((u8*)regs->ip); + + if(res) + regs->ip += res; + else + do_invalid_op(regs, error_code); +} -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Martin Schleier on 6 Nov 2009 10:50 On Fri, 6 Nov 2009 15:59:16 +0100 Matteo Croce wrote: > On Sat, Oct 3, 2009 at 8:21 AM, Ingo Molnar <mingo(a)elte.hu> wrote: > > > > * Matteo Croce <technoboy85(a)gmail.com> wrote: [snip] > > Looks good, but your signoff line is missing. > > > > Ingo > > > > The AMD Geode LX has an x86 id of 5 (i586) tought it's technically an > i686: > > root(a)alix:~# egrep '^(cpu family|model name|flags)' /proc/cpuinfo > cpu family : 5 > model name : Geode(TM) Integrated Processor by AMD PCS > flags : fpu de pse tsc msr cx8 sep pge cmov clflush mmx > mmxext 3dnowext 3dnow > > indeed it has MMX, MMXEXT and CMOV, just lacks the long NOP instruction > (NOPL). > This patch adds a quirck to promote the Geode to an i686 and emulates > the NOPL in the do_invalid_op trap, so the userspace never notices. > Emulating the NOPL has minimum performance loss, emulating a NOPL > takes 0.5 usecs > and they are rarely used in x86 > > Signed-off-by: Matteo Croce <technoboy85(a)gmail.com> > > --- a/arch/x86/kernel/Makefile 2009-11-06 15:06:52.246223989 +0100 > +++ b/arch/x86/kernel/Makefile 2009-11-06 15:07:04.294054613 +0100 > @@ -89,7 +89,7 @@ > obj-$(CONFIG_HPET_TIMER) += hpet.o > > obj-$(CONFIG_K8_NB) += k8.o > -obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o > +obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o nopl_emu.o > obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o > obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o > > --- a/arch/x86/kernel/cpu/amd.c 2009-11-06 15:06:52.254223805 +0100 > +++ b/arch/x86/kernel/cpu/amd.c 2009-11-06 15:07:04.294054613 +0100 > @@ -138,8 +138,10 @@ > } > > if (c->x86_model == 10) { > - /* AMD Geode LX is model 10 */ > - /* placeholder for any needed mods */ > + /* Geode only lacks the NOPL instruction to be i686, > + but we can emulate it in the exception handler > + and promote it to a class 6 cpu */ > + boot_cpu_data.x86 = 6; > return; > } > } > --- a/arch/x86/kernel/entry_32.S 2009-11-06 15:06:52.258224172 +0100 > +++ b/arch/x86/kernel/entry_32.S 2009-11-06 15:07:04.306230613 +0100 > @@ -901,7 +901,11 @@ > RING0_INT_FRAME > pushl $0 > CFI_ADJUST_CFA_OFFSET 4 > +#ifdef CONFIG_MGEODE_LX > + pushl $do_nopl_emu > +#else > pushl $do_invalid_op > +#endif > CFI_ADJUST_CFA_OFFSET 4 > jmp error_code > CFI_ENDPROC > --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > +++ b/arch/x86/kernel/nopl_emu.c 2009-11-06 15:07:33.537723795 +0100 > @@ -0,0 +1,102 @@ > +/* > + * linux/arch/x86/kernel/nopl_emu.c > + * > + * Copyright (C) 2002 Willy Tarreau > + * Copyright (C) 2009 Matteo Croce > + */ > + > +#include <linux/sched.h> > +#include <linux/linkage.h> > +#include <linux/preempt.h> > +#include <linux/types.h> > + > +void do_invalid_op(struct pt_regs *regs, long error_code); > + > +/* This code can be used to allow the AMD Geode to hopefully correctly > execute > + * some code which was originally compiled for an i686, by emulating > NOPL, > + * the only missing i686 instruction in the CPU > + * > + * Willy Tarreau <willy(a)meta-x.org> > + * Matteo Croce <technoboy85(a)gmail.com> > + */ > + > +static inline int do_1f(u8 *ip) > +{ > + int length = 3; > + switch(*ip) { > + case 0x84:if(!ip[5]) > + length++; > + else > + return 0; > + case 0x80:if(!ip[4] && !ip[3]) > + length += 2; > + else > + return 0; > + case 0x44:if(!ip[2]) > + length++; > + else > + return 0; > + case 0x40:if(!ip[1]) > + length++; > + else > + return 0; > + case 0x00:return length; > + default: return 0; > + } > + return length; > +} > + > +static inline int do_0f(u8 *ip) > +{ > + if(*ip == 0x1f) > + return do_1f(ip + 1); > + return 0; > +} > + > +static inline int do_66(u8 *ip) > +{ > + if(*ip == 0x90) > + return 2; > + if(*ip == 0x0f) { > + int res = do_0f(ip + 1); > + if(res) > + return res + 1; > + else > + return 0; > + } > + return 0; > +} > + > +static inline int do_start(u8 *ip) > +{ > + if(*ip == 0x0f) > + return do_0f(ip + 1); > + if(*ip == 0x66) > + return do_66(ip + 1); > + return 0; > +} > + > +/* [do_nopl_emu] is called by exception 6 after an invalid opcode has > been > + * encountered. It will try to emulate it by doing nothing, > + * and will send a SIGILL or SIGSEGV to the process if not possible. > + * the NOPL can have variable length opcodes: > + > +bytes number opcode > + 2 66 90 > + 3 0f 1f 00 > + 4 0f 1f 40 00 > + 5 0f 1f 44 00 00 > + 6 66 0f 1f 44 00 00 > + 7 0f 1f 80 00 00 00 00 > + 8 0f 1f 84 00 00 00 00 00 > + 9 66 0f 1f 84 00 00 00 00 00 > +*/ > +void do_nopl_emu(struct pt_regs *regs, long error_code) > +{ > + int res = do_start((u8*)regs->ip); > + > + if(res) > + regs->ip += res; > + else > + do_invalid_op(regs, error_code); > +} > -- Looks good? checkpatch.pl has a very different opinion. WARNING: externs should be avoided in .c files #56: FILE: arch/x86/kernel/nopl_emu.c:13: +void do_invalid_op(struct pt_regs *regs, long error_code); ERROR: switch and case should be at the same indent #69: FILE: arch/x86/kernel/nopl_emu.c:26: + switch(*ip) { + case 0x84:if(!ip[5]) [...] + case 0x80:if(!ip[4] && !ip[3]) [...] + case 0x44:if(!ip[2]) [...] + case 0x40:if(!ip[1]) [...] + case 0x00:return length; + default: return 0; ERROR: space required before the open parenthesis '(' #69: FILE: arch/x86/kernel/nopl_emu.c:26: + switch(*ip) { ERROR: space required before the open parenthesis '(' #70: FILE: arch/x86/kernel/nopl_emu.c:27: + case 0x84:if(!ip[5]) ERROR: trailing statements should be on next line #70: FILE: arch/x86/kernel/nopl_emu.c:27: + case 0x84:if(!ip[5]) ERROR: space required before the open parenthesis '(' #74: FILE: arch/x86/kernel/nopl_emu.c:31: + case 0x80:if(!ip[4] && !ip[3]) ERROR: trailing statements should be on next line #74: FILE: arch/x86/kernel/nopl_emu.c:31: + case 0x80:if(!ip[4] && !ip[3]) ERROR: space required before the open parenthesis '(' #78: FILE: arch/x86/kernel/nopl_emu.c:35: + case 0x44:if(!ip[2]) ERROR: trailing statements should be on next line #78: FILE: arch/x86/kernel/nopl_emu.c:35: + case 0x44:if(!ip[2]) ERROR: space required before the open parenthesis '(' #82: FILE: arch/x86/kernel/nopl_emu.c:39: + case 0x40:if(!ip[1]) ERROR: trailing statements should be on next line #82: FILE: arch/x86/kernel/nopl_emu.c:39: + case 0x40:if(!ip[1]) ERROR: space required before the open parenthesis '(' #94: FILE: arch/x86/kernel/nopl_emu.c:51: + if(*ip == 0x1f) ERROR: space required before the open parenthesis '(' #101: FILE: arch/x86/kernel/nopl_emu.c:58: + if(*ip == 0x90) ERROR: space required before the open parenthesis '(' #103: FILE: arch/x86/kernel/nopl_emu.c:60: + if(*ip == 0x0f) { ERROR: space required before the open parenthesis '(' #105: FILE: arch/x86/kernel/nopl_emu.c:62: + if(res) ERROR: space required before the open parenthesis '(' #115: FILE: arch/x86/kernel/nopl_emu.c:72: + if(*ip == 0x0f) ERROR: space required before the open parenthesis '(' #117: FILE: arch/x86/kernel/nopl_emu.c:74: + if(*ip == 0x66) ERROR: "(foo*)" should be "(foo *)" #139: FILE: arch/x86/kernel/nopl_emu.c:96: + int res = do_start((u8*)regs->ip); ERROR: space required before the open parenthesis '(' #141: FILE: arch/x86/kernel/nopl_emu.c:98: + if(res) ERROR: Missing Signed-off-by: line(s) total: 19 errors, 1 warnings, 133 lines checked This patch has style problems, please review. If any of these errors are false positives report them to the maintainer, see CHECKPATCH in MAINTAINERS. -- DSL-Preisknaller: DSL Komplettpakete von GMX schon f�r 16,99 Euro mtl.!* Hier klicken: http://portal.gmx.net/de/go/dsl02 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Alan Cox on 6 Nov 2009 11:00 > Looks good? checkpatch.pl has a very different opinion. Firstly please learn to trim your email Secondly Ingo knows how to operate checkpatch and trivial style bits like that are irrelevant to meaningful discussion about code Alan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Matteo Croce on 6 Nov 2009 11:50 On Fri, Nov 6, 2009 at 4:59 PM, Alan Cox <alan(a)lxorguk.ukuu.org.uk> wrote: >> Looks good? checkpatch.pl has a very different opinion. > > Firstly please learn to trim your email > Secondly Ingo knows how to operate checkpatch and trivial style bits like > that are irrelevant to meaningful discussion about code > > > Alan > I fixed the style issues with checkpatch.pl, here is it. The AMD Geode LX has an x86 id of 5 (i586) tought it's technically an i686: root(a)alix:~# egrep '^(cpu family|model name|flags)' /proc/cpuinfo cpu family : 5 model name : Geode(TM) Integrated Processor by AMD PCS flags : fpu de pse tsc msr cx8 sep pge cmov clflush mmx mmxext 3dnowext 3dnow indeed it has MMX, MMXEXT and CMOV, just lacks the long NOP instruction (NOPL). This patch adds a quirck to promote the Geode to an i686 and emulates the NOPL in the do_invalid_op trap, so the userspace never notices. Emulating the NOPL has minimum performance loss, emulating a NOPL takes 0.5 usecs and they are rarely used in x86 Signed-off-by: Matteo Croce <technoboy85(a)gmail.com> --- a/arch/x86/kernel/Makefile 2009-11-06 15:06:52.246223989 +0100 +++ b/arch/x86/kernel/Makefile 2009-11-06 15:07:04.294054613 +0100 @@ -89,7 +89,7 @@ obj-$(CONFIG_HPET_TIMER) += hpet.o obj-$(CONFIG_K8_NB) += k8.o -obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o +obj-$(CONFIG_MGEODE_LX) += geode_32.o mfgpt_32.o nopl_emu.o obj-$(CONFIG_DEBUG_RODATA_TEST) += test_rodata.o obj-$(CONFIG_DEBUG_NX_TEST) += test_nx.o --- a/arch/x86/kernel/cpu/amd.c 2009-11-06 15:06:52.254223805 +0100 +++ b/arch/x86/kernel/cpu/amd.c 2009-11-06 15:07:04.294054613 +0100 @@ -138,8 +138,10 @@ } if (c->x86_model == 10) { - /* AMD Geode LX is model 10 */ - /* placeholder for any needed mods */ + /* Geode only lacks the NOPL instruction to be i686, + but we can emulate it in the exception handler + and promote it to a class 6 cpu */ + boot_cpu_data.x86 = 6; return; } } --- a/arch/x86/kernel/entry_32.S 2009-11-06 15:06:52.258224172 +0100 +++ b/arch/x86/kernel/entry_32.S 2009-11-06 15:07:04.306230613 +0100 @@ -901,7 +901,11 @@ RING0_INT_FRAME pushl $0 CFI_ADJUST_CFA_OFFSET 4 +#ifdef CONFIG_MGEODE_LX + pushl $do_nopl_emu +#else pushl $do_invalid_op +#endif CFI_ADJUST_CFA_OFFSET 4 jmp error_code CFI_ENDPROC --- /dev/null 1970-01-01 00:00:00.000000000 +0000 +++ b/arch/x86/kernel/nopl_emu.c 2009-11-06 17:36:40.684361766 +0100 @@ -0,0 +1,106 @@ +/* + * linux/arch/x86/kernel/nopl_emu.c + * + * Copyright (C) 2002 Willy Tarreau + * Copyright (C) 2009 Matteo Croce + */ + +#include <linux/sched.h> +#include <linux/linkage.h> +#include <linux/preempt.h> +#include <linux/types.h> + +void do_invalid_op(struct pt_regs *regs, long error_code); + +/* This code can be used to allow the AMD Geode to hopefully correctly execute + * some code which was originally compiled for an i686, by emulating NOPL, + * the only missing i686 instruction in the CPU + * + * Willy Tarreau <willy(a)meta-x.org> + * Matteo Croce <technoboy85(a)gmail.com> + */ + +static inline int do_1f(u8 *ip) +{ + int length = 3; + switch (*ip) { + case 0x84: + if (!ip[5]) + length++; + else + return 0; + case 0x80: + if (!ip[4] && !ip[3]) + length += 2; + else + return 0; + case 0x44: + if (!ip[2]) + length++; + else + return 0; + case 0x40: + if (!ip[1]) + length++; + else + return 0; + case 0x00:return length; + default: return 0; + } + return length; +} + +static inline int do_0f(u8 *ip) +{ + if (*ip == 0x1f) + return do_1f(ip + 1); + return 0; +} + +static inline int do_66(u8 *ip) +{ + if (*ip == 0x90) + return 2; + if (*ip == 0x0f) { + int res = do_0f(ip + 1); + if (res) + return res + 1; + else + return 0; + } + return 0; +} + +static inline int do_start(u8 *ip) +{ + if (*ip == 0x0f) + return do_0f(ip + 1); + if (*ip == 0x66) + return do_66(ip + 1); + return 0; +} + +/* [do_nopl_emu] is called by exception 6 after an invalid opcode has been + * encountered. It will try to emulate it by doing nothing, + * and will send a SIGILL or SIGSEGV to the process if not possible. + * the NOPL can have variable length opcodes: + +bytes number opcode + 2 66 90 + 3 0f 1f 00 + 4 0f 1f 40 00 + 5 0f 1f 44 00 00 + 6 66 0f 1f 44 00 00 + 7 0f 1f 80 00 00 00 00 + 8 0f 1f 84 00 00 00 00 00 + 9 66 0f 1f 84 00 00 00 00 00 +*/ +void do_nopl_emu(struct pt_regs *regs, long error_code) +{ + int res = do_start((u8 *)regs->ip); + + if (res) + regs->ip += res; + else + do_invalid_op(regs, error_code); +} -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: H. Peter Anvin on 6 Nov 2009 11:50
On 11/06/2009 06:59 AM, Matteo Croce wrote: > indeed it has MMX, MMXEXT and CMOV, just lacks the long NOP instruction (NOPL). MMX and MMXEXT are hardly hallmarks of i686, which leaves only cmov. I'm somewhat wondering about the general value of this patch; is i686 code really that much faster on Geode that it's worth it? -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |