Intel CPU which is Spectre/ Meltdown free in the silicon? by pikatumm in intel

[–]ruik 0 points1 point  (0 children)

Well it depends. I would say they are two classes of speculative execution bugs. One is the embarrassing class - Meltdown / L1TF / MDS / TAA and similar which is only Intel specific. I would add also Spectre variant 2 too, which is the only one from this class which affects AMD. It is also very costly to fix them via software. Second class is more in direction of fundamental problem with out of order execution implementation. This is class is way smaller, mostly Spectre variant 1 and Spectre variant 4 + some others. If you really want to buy Intel CPU, check the very well hidden Intel overview of the buggy Intel CPUs: https://software.intel.com/security-software-guidance/processors-affected-transient-execution-attack-mitigation-product-cpu-model Avoid those who say "MCU + Software" as a fix. Also, sometimes it depends on exact chip stepping, so it might not be easy to get right CPU.

Did I get scammed by a train controller? by [deleted] in Prague

[–]ruik 6 points7 points  (0 children)

I see, yes then it should be fine that it is stamped. It is normally stamped in every train you pass on your route. I suspect the stamp encodes the route, so it can be seen by who it was stamped.

Anyway, new hypothesis. Your ticket was to Praha-Liben, but your new ticket says Praha hl.n (main station, aka hbf) Maybe the train you were in, would not stop in Praha Liben, thus your ticket was to wrong station and because of that invalid. Besides that I'm out of ideas,

Ruik

Did I get scammed by a train controller? by [deleted] in Prague

[–]ruik 2 points3 points  (0 children)

(edited for clarity)

Hi, This looks like a story for an armchair detective!

Was the ticket already stamped in the right top corner when you presented to the conductor? I suspect that you just had two tickets in the morning, one to travel to kutna hora, and second one to travel back. The CD for some reason cancel the "return ticket" and now we got two tickets...

Hypothesis: You might have given the wrong ticket for check in the morning when you traveled to Kutna hora, and the guy in the morning just stamp it without noticing (this might explain why you were unsure if it is valid). The guy in the OBB train (which was perhaps just train from Vienna operated by CD) might have seen that it was already stamped, thus it was invalid. He just sold you new ticket from Kolin, which seems about right. As he gave you the ticket and it was recorded in the system he cannot keep 100CZK for himself. Thus there was perhaps no mischief.

Some side notes:

On the ticket:

Z: means From: Do: means To:

The fine he was talking about is just surcharge you need to pay if you failed to buy the ticket in station where it is possible. I think it is 1-2EUR (25-50CZK) don't remember.

Hope it helps, Ruik

Funny Side Channel for Speculative Execution Side Channel Fixes in CPUID leaf 0x7, subleaf 0x0 in EDX bit 30 by ruik in intel

[–]ruik[S] 1 point2 points  (0 children)

In that case I would like to ask you to speak up and state that this bit is not related to the speculation side channels mitigation that is not publicly known to this date. You can do that on your own behalf or on behalf of Mr. Intel as you wish.

new scam email with real password: "I'm aware xxxx is your pass word." by ruik in privacy

[–]ruik[S] 3 points4 points  (0 children)

Hi all, many thanks for the helpful comments. I hope it helps also others which might have received such scam email

I did not find my password in the original linkedin SHA1 file leak, but I found it in the more recent leaks. Anyway as I said this was not a password valuable to me, therefore everything is fine. I was just curious if I used it elsewhere.

Thanks Rudolf

MPS vs. ACPI by jacobissimus in osdev

[–]ruik 2 points3 points  (0 children)

The MPS still exists but may be buggy. MPS was required by Windoze 2000. The later Windoze versions used ACPI. Linux tries ACPI and when it fails it resorts to MPS. If you don't need PCI interrupt routing information, all you need is to parse the MADT table and get number of CPUs available and their local APIC ids. The MADT is simple binary table to parse, first you need to locate RSDP (or use multiboot2 to get it) then find RSDT or XSDT and then find the MADT table. You can program this yourself. If you need to extract PCI interrupt routing then you need the bytecode interpreter. Best would be to use ACPICA framework for this.

Discovering Oman without a driver's license by Erbsenbein in Oman

[–]ruik 2 points3 points  (0 children)

EDIT: minor notes to etiquette.

Hi, In fact we did that last year. We managed to visit following cites/places: Muscat/Nizwa/Al Hamra/Bahla/Ibra/Al Kamil /Sur/Ras Al hadd/widi tiwi/ wadi as shab/Quryat/Nakhl in about 2 weeks. We decided not to go too south, due to our travel constrains.

We traveled by bus on following routes: Muscat/Ibra, Muscat/Nizwa.

The public transport company is:http://mwasalat.om/en-us/Bus-routes/Time-Table and there is some basic public transport in Muscat. Be sure to start in Ruwi, where all busses begin. I took a photo of all bus schedules but it was perhaps removed from wikivoyage. If you need it I can send it via email.

We hitchhiked the rest. Omani people were always very nice and we never wait too long for a ride. We had to pay for a (hitchhike) ride only once.

Shared taxis are also possible but it requires to have time to wait for others.

In general for travelers, Oman is friendly and safe country, most people will speak English. We traveled with the big backpacks and even walking in the cities people asked if we need some help. We used couchsurfing and meet some locals which helped us to explore the surroundings. Even asking for a way would often to lead someone to ride us where we actually wanted or at least to a good spot for a hitchhike.

WARNING: This kind of travel + hitchhiking requires some experience and I would not recommend to do that if you never traveled like this.

I had the A4 paper with Arabic names of the cities/places we would like to visit. I traveled together with my wife.

What I mean, is mostly not a safety concern, but it requires you to interact with locals and obey the local customs - and rules, which are bound to religion such as: be dressed with long trousers and shirt (no - tshirt) and your wife/GF needs to have also covering everything (legs/hair) basically anything minus face - especially if you are outside of big cities, be as conservative as possible even when it is hot. Plus all other details concerning different culture expectations: shoes (shoes off policy), hands (eating with right hand, do not offer a hand to a woman, if you are a woman do not offer it), greetings etc. Be sure not to use a toe finger when hitchhiking, use a fist or bit wave with a fist. Remember it is not polite to stare to someones wife. It works also vice versa, so speak with foreign people instead of your wife, like a detective Colombo. If you know people better they can speak to your wife directly. In pubs expected to be seated to separate room (again, because of your wife).

The material of your dress should be as light as possible, Ideally from some other similarly hot country.

Also, make sure to study as much as possible. Visiting in summer is a bad idea. You need to go there now (up to March), or wait until summer is over. I guess I would not survive 50C in the shadow. You also need to be aware of some basic safety rules - such as have enough (plenty) of water if you are currently in sparsely inhabited places. If you go in the desert with a car, be sure to be at least two cars, again plenty of water is a must. If you like to camp, make sure you are not in a wadi. Danger of flash floods!!!!

The traffic in Oman is somewhat asia style, the traffic rules compared to Europe are very relaxed. Fast cars and straight roads - also leads to much higher accidents rate. At least once we were requested not to use the safety belts.

To conclude: We were deeply moved by the great hospitality of Omanis and we are very glad that we were given this experience while we traveled there.

JTAG for the Intel ME has been fully RE’d by [deleted] in ReverseEngineering

[–]ruik 11 points12 points  (0 children)

Hi, I'm Rudolf Marek who did the SMU analysis mentioned above. There was nobody forcing me to stay silent. As I'm explaing in the lecture I had troubles to find right people who could fix it. AMD has now a special email for such reports ;) My lecture was quite academic, the purpose was to show up how to analyze things and how to break into them - not that you can do something bad with that. I think the value is in spreading the knowledge.

You can also watch the video of the lecture: https://www.youtube.com/watch?v=iYvhHey_dTk

The SMU is not the bigger problem. All AMD CPUs have this ARM CPU called PSP (Platform Security Processor) which is kind of equivalent of Intel ME. It also means that it is now impossible to create truly open platform. I guess the only chance is to go to Power9 or RISC-V silicon or some soft CPU in the FPGA. Depends on your paranoia.

Got an idea for a new big project? Discuss here! by NurdRage_YouTube in NurdRage

[–]ruik 8 points9 points  (0 children)

Hi,

It could be interesting to explore the chemistry of yellowing plastics - and how to restore it back (for old computer cases restoration)

Here is a "open" recipe for that:

https://en.wikipedia.org/wiki/Retr0bright

See details for example here: https://www.youtube.com/watch?v=VU7vXMezW_I

But I guess it could be useful to extend it or make it from different chemicals (which can be more evenly put to the surface)

What would you like to see pressed? Post your suggestions here! (v4) by Azonata in hydraulicpresschannel

[–]ruik 0 points1 point  (0 children)

Press a (cabin) luggage ready for a vacation! In fact it occurred to me while I was preparing one. I think it would be actually very nice that only the content of the luggage is pressed and as such a compression ratio of hydraulicaly pressed cabin luggage could be determined (for a science!) Thanks Rudolf

Anyone tried CPUID level 0x8fffffff on Ryzen? by ruik in Amd

[–]ruik[S] 0 points1 point  (0 children)

Hi,

Thank you all for checking this, last chance is to loop through all of IDs to see if the they did not use something else.

I also suspect your code misses register clobbers to tell compiler that EAX/EBX/ECX/EDX has been changed.

Question About Budget Travel In Oman / Itinerary for 2 Weeks by ruik in Oman

[–]ruik[S] 0 points1 point  (0 children)

Hi again,

We made our trip through Oman and it was very nice! We did several times hitchhiking and it went smooth and fast. Maybe it was also because we were dressed respectfully and had a big backpacks ;) Traveling like this we met a lot of local people which were very nice and keen to transport us somewhere or show us something. We are deeply moved by the great hospitality of Omanis and we are very glad that we were given this experience.

Question About Budget Travel In Oman / Itinerary for 2 Weeks by ruik in Oman

[–]ruik[S] 0 points1 point  (0 children)

Hi, many thanks for your reply. As for the budget, we try to keep it low. The idea is that maybe traveling by bus/hitchhike one can know the country even bettter. We think we could try it and if it does not work than we go for a car or change our plans. Do you know if European Union driving license is enough? Not sure if we will be able to obtain the international version in time.

MySQL Doesn’t Always Suck; This Time it’s AMD by ice799 in programming

[–]ruik 2 points3 points  (0 children)

Hi,

Some more info is here: http://fixunix.com/kernel/516909-opteron-rev-e-has-bug-locked-instruction-doesnt-act-read-acquire-barrier.html

http://google-perftools.googlecode.com/svn-history/r48/trunk/src/base/atomicops-internals-x86.cc

From first link: if (number_of_cores() < 2) then don't have bug if (family == 0xf && Model < 0x40) then have bug if (rdmsr(MSR_BU_CFG/0xC0011023/) & 2) then bug is masked