lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 26 Nov 2008 17:45:11 +0100 From: Andi Kleen <andi@...stfloor.org> To: eranian@...il.com Cc: Thomas Gleixner <tglx@...utronix.de>, linux-kernel@...r.kernel.org, akpm@...ux-foundation.org, mingo@...e.hu, x86@...nel.org, andi@...stfloor.org, sfr@...b.auug.org.au Subject: Re: [patch 21/24] perfmon: Intel architectural PMU support (x86) > Both perfmon_intel_arch.c and perfmon_amd64.c are supposed to be kernel modules. > They are hardcoded right now to make the patch simpler. Have PMU description be > modules is a key features because it allows adding new processor support without > necessarily patch the core kernel or rebooting. This has been working To install the new processor in the first place you have to reboot anyways. Also typically at least for new families (which tend to be the only ones with radically new performance counters) it's typically needed to change some things in the core kernel anyways. So this doesn't seem like a really useful feature. > nicely on Itanium. > With the introduction of Intel architectural Perfmon (IA32 SDM chapter > 18), this becomes > possible on Intel X86 as well. It becomes possible, but without having to use any modules. It should just work. Probably even without it worked -- at least if you limit yourself to family 6 -- because the register layout all stayed the same too. That said having modular PMUs is probably a good thing for distribution kernels, but there is really no need for any code compromises just to avoid a core kernel patch now and then. -Andi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists