| 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: Thu, 01 Mar 2012 10:19:39 -0300 From: Mauro Carvalho Chehab <mchehab@...hat.com> To: Borislav Petkov <bp@...64.org> CC: "Luck, Tony" <tony.luck@...el.com>, Ingo Molnar <mingo@...e.hu>, EDAC devel <linux-edac@...r.kernel.org>, LKML <linux-kernel@...r.kernel.org> Subject: Re: [PATCH 1/3] mce: Add a msg string to the MCE tracepoint Em 01-03-2012 08:29, Borislav Petkov escreveu: > On Wed, Feb 29, 2012 at 05:33:51PM +0000, Luck, Tony wrote: >>> IOW, we want to assume that cores 0, 1, 2 ... k-1 are on node 0; k, k+1 >>> ... 2k-1 belong to node 1, etc., where k is the number of cores on a >>> socket and thus we have a regular core enumeration on the box. >> >> Sounds dubious: >> >> Booting Node 0, Processors #1 #2 #3 #4 #5 #6 #7 Ok. >> Booting Node 1, Processors #8 #9 #10 #11 #12 #13 #14 #15 Ok. >> Booting Node 0, Processors #16 #17 #18 #19 #20 #21 #22 #23 Ok. >> Booting Node 1, Processors #24 #25 #26 #27 #28 #29 #30 #31 >> Brought up 32 CPUs >> >> Now those are logical cpu numbers, and we brought up the first HT >> thread on each core first, and then came around for a 2nd pass >> bringing up the other HT thread. This order is determined by >> how the BIOS lists the cpus (and in this case it seems to be >> doing so according to recommendations) - so here our core numbers >> will match what you said. But the BIOS could do something >> strange and list logical cpus alternating between sockets. In >> which case cores 0, 2, 4, 6 ... would be on node 0, and cores >> 1, 3, 5, 7, ... on node 1. > > Ok, the example above actually confirms my fear that you won't be always > able to map back to a physical socket from the CPU number. So, we'll > need the ->socketid field which is the physical processor ID we get from > CPUID leafs. > > Then, mapping back the socketid to the silkscreen labels on the boards > should be easy because on the boxes I have here, they go like this: P0, > P1, ..., where P0 is the socket containing the BSP, P1 is the second > socket etc. I'm guessing this is similar on Intel boards...? The mapping from socket id to silkscreen label is motherboard-dependent. I did some tests with a few different machines: [root@...l-pe1950-05 ~]# dmidecode | grep -i "Processor Information" -A10 Processor Information Socket Designation: CPU1 Type: Central Processor Family: Xeon Manufacturer: Intel ID: F6 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 6 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: CPU2 Type: Central Processor Family: Xeon Manufacturer: Intel ID: F6 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 6 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) [root@...dl580g5-01 ~]# dmidecode | grep -i "Processor Information" -A10 Processor Information Socket Designation: Proc 1 Type: Central Processor Family: Xeon MP Manufacturer: Intel ID: FB 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 11 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: Proc 2 Type: Central Processor Family: Xeon MP Manufacturer: Intel ID: FB 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 11 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: Proc 3 Type: Central Processor Family: Xeon MP Manufacturer: Intel ID: FB 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 11 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: Proc 4 Type: Central Processor Family: Xeon MP Manufacturer: Intel ID: FB 06 00 00 FF FB EB BF Signature: Type 0, Family 6, Model 15, Stepping 11 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) dmidecode | grep -i "Processor Information" -A10 Processor Information Socket Designation: CPU 1 Type: Central Processor Family: Pentium M Manufacturer: Intel ID: A4 06 01 00 FF FB EB BF Signature: Type 0, Family 6, Model 26, Stepping 4 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: CPU 2 Type: Central Processor Family: Pentium M Manufacturer: Intel ID: A4 06 01 00 FF FB EB BF Signature: Type 0, Family 6, Model 26, Stepping 4 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) [root@...bl260cg5-01 ~]# dmidecode | grep "Processor Information" -A10 Processor Information Socket Designation: Proc 1 Type: Central Processor Family: Xeon Manufacturer: Intel ID: 76 06 01 00 FF FB EB BF Signature: Type 0, Family 6, Model 23, Stepping 6 Flags: FPU (Floating-point unit on-chip) VME (Virtual mode extension) DE (Debugging extension) -- Processor Information Socket Designation: Proc 2 Type: Central Processor Family: Xeon Manufacturer: Intel ID: 00 00 00 00 00 00 00 00 Signature: Type 0, Family 0, Model 0, Stepping 0 Flags: None Version: Not Specified Voltage: 1.1 V External Clock: 200 MHz On all the above, the socket label starts on 1, but I bet we'll find cases where it start from 0. Regards, Mauro -- 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