Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8 • Hacker News Board

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#41

Post by sliken » Fri, Nov 03, 2023, 4:27 PM UTC

galangalalgol wrote: post #29

mikae1 wrote: post #22

Earlier quoted context omitted.

Writing this from a Pixel running GrapheneOS. I've been away from Graphene (using Lineage) since the CopperheadOS days. Coming back I can safely say I will be buying Pixels as long as GrapheneOS is around. The robustness a finish is just amazing. To anyone using a Pixel: install and donate (if you can)! The web installer[1] is basically a few clicks on a web page. So damned impressed. [1] https://grapheneos.org/insta…

Do you lose the whole play store? Does it even make sense if I use gmail? I like the idea at least. And my 4a isn't getting updates now(on graphene either apparently) which is a shame because I still like it. I used to ise lineage on Samsung devices.

Play store is available, just not installed by default. It also lives in a sandbox so has to ask for permission more than it does under standard android.

I never realized how many permissions the play store had, until I ran it under graphene.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#42

Post by CuriousCosmic » Fri, Nov 03, 2023, 4:41 PM UTC

jchw wrote: post #32

piaste wrote: post #30

Earlier quoted context omitted.

> What I'd hope to hear is that Daniel Micay is in better mental health, but they made the almost-certainly wise choice to stop engaging with social media, and I can't find much information about what actually went down, so I guess it's a question mark. I mean, it sounds like you have pretty much all the relevant information already? strcat's technical chops were AFAIK never in question, but he had a tendency to pick…

I was curious if that actually happened or not. However, I didn't actually see anything about GrapheneOS's leadership structure, or any kind of blog or anything where news like this would be announced. So if it happened, who replaced them? Are they trustworthy? At least in my cursory searching, I didn't figure out an answer to that. I assume the answer is actually out there, but I don't have it. > Whether he still lu…

> So if it happened, who replaced them? Are they trustworthy? At least in my cursory searching, I didn't figure out an answer to that.

https://github.com/thestinger/daniel.micay.dev/commit/79e44b...

They just stepped down as the official head and stopped making public comments. They still are a major developer for the project and still seem to own/run parts of the project.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#43

Post by CuriousCosmic » Fri, Nov 03, 2023, 4:43 PM UTC

vzaliva wrote: post #37

I would love to hear a first-hand report of running in this mode from a week or two. Any bugs? Performance isses?

GrapheneOS runs with MTE on by default and it works great. I can't speak to issues with stock AOSP or Pixel roms but if there are issues, the GrapheneOS team has patched over them well enough that I haven't noticed one yet

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#44

Post by j1elo » Fri, Nov 03, 2023, 5:00 PM UTC

tuukkah wrote: post #20

j1elo wrote: post #18

Earlier quoted context omitted.

Sadly they contain some options which ought to be part of the normal system settings, but they aren't. Such as animation speed. I hate _so much_ all the wobblyness of the GUI! Everything bouncing, sliding, and hovering around. Thankfully one can enable Developer options and set all that stuff to 0x, which effectively disables everything and now the system becomes crisp and instant, as it should be. Another essential…

Also, configure "Smallest width" to a high dp value to fit more content on the screen.

For sure! that one is a very good candidate for basic option to tune on any phone. I always up it a bit to gain more screen estate.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#45

Post by jchw » Fri, Nov 03, 2023, 5:26 PM UTC

CuriousCosmic wrote: post #42

jchw wrote: post #32

Earlier quoted context omitted.

I was curious if that actually happened or not. However, I didn't actually see anything about GrapheneOS's leadership structure, or any kind of blog or anything where news like this would be announced. So if it happened, who replaced them? Are they trustworthy? At least in my cursory searching, I didn't figure out an answer to that. I assume the answer is actually out there, but I don't have it. > Whether he still lu…

> So if it happened, who replaced them? Are they trustworthy? At least in my cursory searching, I didn't figure out an answer to that. https://github.com/thestinger/daniel.micay.dev/commit/79e44b... They just stepped down as the official head and stopped making public comments. They still are a major developer for the project and still seem to own/run parts of the project.

That's an orphaned commit on their personal website (and that text doesn't appear anywhere on it), and still nobody seems to have any idea who has taken their place. I don't believe that someone should be eternally punished because of making poor decisions, and with time even a pattern of poor decisions can be forgiven, but as it stands from the outside there's zero clarity on what, if anything, actually happened, no apologies, and ultimately no way to know who you're trusting when you install GrapheneOS.

On one hand, the track record for the actual OS is still completely fine as far as anyone knows. On the other hand, the stuff said and done on record is pretty tough to swallow for someone you are investing a lot of trust into, for an OS that is meant to be privacy and security focused.

Like. It's one thing if you are a casual user running random ROMs off XDA, the risk is high and the only real assurance you get is online reputation and the normal assurances of social pressure. But this is software endorsed by Edward Snowden and many others whose opinions regarding security and privacy are well-regarded. The stakes could be quite high for some users. In the light of that, I really don't like the situation here at all.

Dismiss it if you want to, but there's really absolutely no good reason for this to simply remain effectively unaddressed indefinitely.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#46

Post by LoganDark » Fri, Nov 03, 2023, 7:52 PM UTC

akyuu wrote: post #11

LoganDark wrote: post #7

Earlier quoted context omitted.

Is this the outcome of the Morello project? Honestly sounds nice.

No, AFAIK Morello project is about designing an Arm CPU with CHERI, a hardware architecture with extra security capabilities that is still WIP: https://tratt.net/laurie/blog/2023/two_stories_for_what_is_c...

I've been trying to get a Morello board for months, but they only offer them to large research institutions, not individuals who just want a hobby project. I'm aware of CHERI being different from this, but it still seems similar.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#47

Post by hmry » Fri, Nov 03, 2023, 8:50 PM UTC

pjmlp wrote: post #40

soulbadguy wrote: post #15

Sounds very useful. Even just for testing. Does x86 have something comparable?

They did, MPX, however the design was buggy and eventually removed. Currently x86 is the only mainstrem architecture without a plan for hardware memory tagging. Even RISC-V has an ongoing discussion for hardware memory tagging extensions.

If AMD and Intel drag their feet long enough, CHERI will be production ready before then.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#48

Post by _ea1k » Fri, Nov 03, 2023, 8:56 PM UTC

I just wish there were a great virtual machine manager for Pixels. Apparently it is now possible without root, but only nestbox is available, AFAIK. It might be ok, but the monthly fee isn't a great deal, IMO.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#49

Post by jetbalsa » Fri, Nov 03, 2023, 9:30 PM UTC

piaste wrote: post #31

galangalalgol wrote: post #29

Earlier quoted context omitted.

Do you lose the whole play store? Does it even make sense if I use gmail? I like the idea at least. And my 4a isn't getting updates now(on graphene either apparently) which is a shame because I still like it. I used to ise lineage on Samsung devices.

One of GrapheneOS's absolute best features is the sandboxed Google Play Services. Basically, where other privacy AOSP forks typically offer up to three choices... - no Google at all - root and install an extremely fragile FOSS alternative GPS implementation (MicroG) - root and install the full Google Play Services binary blobs ... GrapheneOS offers option #4: you can install Google Play Services in a sandbox so that…

One of the things that Graphene doesn't support is Android Auto -- They have stated they will never support it due to the sheer rootkit levels that Android Auto does to the OS. Its a shame they have not found a good work around for it yet.

Re: Enable ARMv9 Memory Tagging Extension (MTE) on Pixel 8

#50

Post by muricula » Fri, Nov 03, 2023, 9:32 PM UTC

maxloh wrote: post #2

Why isn't it enabled by default?

There is almost certainly a performance and battery life hit. Each pointer dereference will trigger a lookup in the MTE tag table, and a comparison between the pointer's tag and the table's tag.

So you have a decently sized chunk of RAM set aside for the tag table, more memory bandwidth used up by table lookups, and the cost of the actual tag checks.