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2025-10-28.log

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<laurenth>cosinusoidally: This PR replaces mmap syscalls with brk: https://github.com/udem-dlteam/pnut/pull/209. Pnut-exe now only needs the brk, open, close, read, write and exit syscalls
<Googulator>Besides builder-hex0, is there any other kernel (that matters today) that doesn't support Linux's anonymous MMAP in a compatible way?
<Googulator>I'd much rather have the bootstrap standardize on mmap-anon than on brk, given that brk is considered completely obsolete by POSIX
<Googulator>OTOH mmap-anon is just plain absent from POSIX standards, which instead say that the memory allocation interface is standardized at libc level only
<Googulator>but IMO it seems easier to lobby for standardizing the anonymous argument to mmap than for undeprecating brk, which was actually deprecated for a very good reason (to allow POSIX compliance of systems that can't physically have a flat memory map in user mode)
<matrix_bridge><Andrius Štikonas> Googulator: posix runner possibly
<matrix_bridge><Andrius Štikonas> On uefi
<Googulator>didn't we have the opposite issue with posix-runner, i.e. that UEFI can only implement the equivalent of mmap, not brk?
<matrix_bridge><Andrius Štikonas> Uefi itself yes
<matrix_bridge><Andrius Štikonas> Anyway, probably mmap can be implemented but we would need to set up paging
<matrix_bridge><Andrius Štikonas> Right now it pre-reserves huge chunk of memory from uefi and then uses it as brk region
<matrix_bridge><Andrius Štikonas> https://git.stikonas.eu/andrius/stage0-uefi/src/commit/8a3c3b6b009fe53fea8b847e8dc667e390164e59/posix-runner/posix-runner.c#L221