8 ms·

Apparently it's about software, not hardware - Qualcomm recommends running Android under a virtual machine (which lacks nested virtualization support).

by fulafel 9mo ago

deleted 9mo ago
[deleted]
superb_dev 9mo ago
Is this for real? Do you have any more info on this? It seems crazy to me given how popular their chips are and how many problems I’d imagine this creates
- asutor 9mo ago
  Using an S24 here and yeah, not available with Android 16
  - wolvoleo 9mo ago
    But the S24 wasn't Qualcomm but Exynos. Weird.
- pierrec 9mo ago
  It shouldn't be problematic if the processor supports it well. For example modern Windows is always running as a VM and people are barely aware of that.
  - superb_dev 9mo ago
    That’s a good point, I forgot windows typically runs on top of hyperV
- fulafel 9mo ago
  Some more info in this comment and good search terms for further research as well. https://news.ycombinator.com/item?id=38091082 https://news.ycombinator.com/item?id=38091082
- user_7832 9mo ago
  The other HN comment already has some info, but from what I remember from r/android threads, it's because qualcomm doesn't allow unsecure (sic? unencrypted?) VMs, which, ironically, are needed to run nested Linux. Disclaimer, my memory on the exact terminology is extremely fuzzy. But pixels with tensor can run it just fine. And it's purely a software thing too, btw.
- jeroenhd 9mo ago
  It should work fine for any Android phone with pKVM support. It runs Debian in a VM, with some kind of Wayland trick (using virgl for GPU acceleration) to get GUI support. pKVM requires a) a compatible CPU (most CPUs will do, probably), b) compatible firmware/bootloader software, and c) a compatible Android build The latter two parts are the most likely reason why not all phones have support for this.
mcbridematt 9mo ago
IIRC Qualcomm smartphone SoCs have always run some kind of hypervisor, I believe it's to allow partitioning of the CPU cores with the modem/DSP. They used to (mid-late 2000s) use an L4 derivative ("REX"?), with the more recent chips (including the 'X' series for PCs) using their homegrown "Gunyah" hypervisor (https://github.com/quic/gunyah-hypervisor https://github.com/quic/gunyah-hypervisor)
- fulafel 9mo ago
  Would be interesting if you know of any evidence about being an architectural hw limitation. Though of course the practical difference may be small if the DRM bootloader enforces loading the hypervisor through cryptographic checksums. But I guess if a customer asked they would allow it and the hardware could do it.

Apparently it's about software, not hardware - Qualcomm recommends running Android under a virtual machine (which lacks nested virtualization support).

by fulafel 9mo ago

Apparently it's about software, not hardware - Qualcomm recommends running Android under a virtual machine (which lacks nested virtualization support).

deleted 9mo ago

[deleted]

superb_dev 9mo ago

Is this for real? Do you have any more info on this? It seems crazy to me given how popular their chips are and how many problems I’d imagine this creates

asutor 9mo ago
Using an S24 here and yeah, not available with Android 16
- wolvoleo 9mo ago
  But the S24 wasn't Qualcomm but Exynos. Weird.
pierrec 9mo ago
It shouldn't be problematic if the processor supports it well. For example modern Windows is always running as a VM and people are barely aware of that.
- superb_dev 9mo ago
  That’s a good point, I forgot windows typically runs on top of hyperV
fulafel 9mo ago
Some more info in this comment and good search terms for further research as well. https://news.ycombinator.com/item?id=38091082 https://news.ycombinator.com/item?id=38091082
user_7832 9mo ago
The other HN comment already has some info, but from what I remember from r/android threads, it's because qualcomm doesn't allow unsecure (sic? unencrypted?) VMs, which, ironically, are needed to run nested Linux. Disclaimer, my memory on the exact terminology is extremely fuzzy. But pixels with tensor can run it just fine. And it's purely a software thing too, btw.
jeroenhd 9mo ago
It should work fine for any Android phone with pKVM support. It runs Debian in a VM, with some kind of Wayland trick (using virgl for GPU acceleration) to get GUI support. pKVM requires a) a compatible CPU (most CPUs will do, probably), b) compatible firmware/bootloader software, and c) a compatible Android build The latter two parts are the most likely reason why not all phones have support for this.

mcbridematt 9mo ago

IIRC Qualcomm smartphone SoCs have always run some kind of hypervisor, I believe it's to allow partitioning of the CPU cores with the modem/DSP. They used to (mid-late 2000s) use an L4 derivative ("REX"?), with the more recent chips (including the 'X' series for PCs) using their homegrown "Gunyah" hypervisor (https://github.com/quic/gunyah-hypervisor https://github.com/quic/gunyah-hypervisor)

fulafel 9mo ago
Would be interesting if you know of any evidence about being an architectural hw limitation. Though of course the practical difference may be small if the DRM bootloader enforces loading the hypervisor through cryptographic checksums. But I guess if a customer asked they would allow it and the hardware could do it.