ARMv8 - Running legacy 32 bit Applications on 64 bit OS

linux arm arm64
MS. picture MS. · Mar 17, 2014 · Viewed 9k times · Source

Going thru the ARMv8 manual, I have the following questions to help understand the big picture.

  1. Can legacy 32 bit app. (ARMv7 or earlier) run as is on the ARMv8 OS?

  2. If the legacy applications need to be rebuilt for ARMv8 and assuming that I rebuild the application as 32 bit (Aarch32), does this need 32 bit OS underlying support? (It is interesting to know how the addressing mechanism works here.)

Please provide references wherever possible.

PS: I am targeting Linux OS with Aarch64 support (3.7 and later)

Answer

Marcin Juszkiewicz picture Marcin Juszkiewicz · Apr 12, 2014

Aarch64 platform may run 32bit ARM but this compatibility is optional.

To run AArch32 binaries you need all libraries application would use in 32bit versions. Same as with i686 binaries on x86-64 systems.

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