for BIT in $(seq 0 31); do make clean && rm -f objs.txt && BIT=$BIT make -j9 && cp arch/x86/boot/bzImage kernel_${BIT}.bzimg && mv objs.txt objs_${BIT}.txt ; donehttps://twitter.com/marcan42/status/928571175210323968 …
Show this thread
-
Surprise, it's Go's fault. Turns out 104 bytes of stack space is not enough when GCC decides to do a 4K stack probe. And stack probes are *exactly* what would cause nondeterministic corruption if another thread races that address!https://github.com/golang/go/issues/20427#issuecomment-343255844 …
Show this thread
So my second time stumbling upon and debugging a Go runtime bug *again* winds up being a problem with Go->C interop. Still not a fan of Go.
-
-
Go doesn't do guard pages?
-
Nope. They do dynamic stack copying/reallocation. Except then they call into C, which doesn't.
End of conversation
New conversation -
-
-
Among the people who use Go daily it's sort of well known that using cgo can be quirky due to all sorts of vague reasons; one learns to expect to pay a performance penalty at best. That runtime VDSO isn't really cgo and that's ok because it makes sense to optimize its performance
-
It's not cgo and that's why it crashes: because it makes assumptions about the vDSO that are not guaranteed by the C ABI that it will play nicely with Go's stack layout. You can't have your cake (funny stacks) and eat it too (call C code on them).
End of conversation
New conversation -
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.