docs/emulation: expand warning about semihosting
A surprising feature of calls like SYS_READC is this can cause QEMU to
indefinitely block as there is no handling for EOF.
Clarifies: https://gitlab.com/qemu-project/qemu/-/issues/1963
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231120150833.2552739-8-alex.bennee@linaro.org>
diff --git a/docs/about/emulation.rst b/docs/about/emulation.rst
index 0ad0b86..a2eefe3 100644
--- a/docs/about/emulation.rst
+++ b/docs/about/emulation.rst
@@ -129,8 +129,9 @@
.. warning::
Semihosting inherently bypasses any isolation there may be between
the guest and the host. As a result a program using semihosting can
- happily trash your host system. You should only ever run trusted
- code with semihosting enabled.
+ happily trash your host system. Some semihosting calls (e.g.
+ ``SYS_READC``) can block execution indefinitely. You should only
+ ever run trusted code with semihosting enabled.
Redirection
~~~~~~~~~~~
