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Orange Pi H3 soc images doesn't have lpae enabled in kernel


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Currently I receive rustc crashes after memory usage get to 3GB (1GB RAM + 2GB SWAP) when building firefox. After looking around why, I found that kernel isn't build with lpae extension.

Although H3 soc supports lpae (Large Physical Address Extension), but kernel has CONFIG_ARM_LPAE flag not set and so we can't use more than 3GB of memory (1GB is reserved for kernel).

(Processors that implement the ARMv7-A Large Physical Address Extension (LPAE), expand the range of accessible physical addresses from 4GB (232 bytes) to 1024GB (240 bytes) a terabyte, by translating 32-bit virtual memory addresses into 40-bit physical memory addresses.)


After looking around I found that there isn't any armbian release where this flag is enabled, but other distros have this correctly enabled by default,

debian https://wiki.debian.org/DebianKernel/ARMMP



I also wonder if used build options are generic or did they make use of CPU extensions. H3 also supports VFPv4 or VFPv4-D32
for H3 example:  -march=armv7ve -mtune=cortex-a7 -mfloat-abi=hard -mfpu=neon-vfpv4


my output from
cat /proc/cpuinfo

    processor       : 3
    model name      : ARMv7 Processor rev 5 (v7l)
    BogoMIPS        : 65.14
    Features        : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm
    CPU implementer : 0x41
    CPU architecture: 7
    CPU variant     : 0x0
    CPU part        : 0xc07
    CPU revision    : 5





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With LPAE enabled, the kernel would be able to work with an overall pool of RAM+SWAP greater than the 32-bit barrier; however, each individual running process would still only have a 32-bit virtual address space and so its slice of the overall pie would still be limited.


Are you certain that it's even possible to compile Firefox in an environment where each individual process cannot grow beyond the bounds of a 32-bit virtual address space? In the official Firefox development docs, the only documented workflow for compiling a 32-bit Linux target specifies that it should be cross-compiled from a 64-bit host.

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