darwin,linux: more conservative minimum stack size

uv_thread_create() inspects min(PTHREAD_STACK_MIN, RLIMIT_STACK) to
find out the minimum allowed stack size. After spelunking through
kernel and libc code, I came to the conclusion that allowing such
small stacks does not mix well with signals.

Musl's PTHREAD_STACK_MIN is 2 KB but signal handlers on many
architectures need at least 1 KB to store the signal context,
making it almost impossible to do anything on the thread without
signal delivery overflowing the stack.

Therefore, increase the lower bound to 8 KB. That corresponds to
PTHREAD_STACK_MIN + MINSIGSTKSZ on arm64, which has the largest
MINSIGSTKSZ of the architectures that musl supports.

PR-URL: https://github.com/libuv/libuv/pull/2310
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

0 files changed, 0 insertions, 0 deletions