From: Alex Bennée Date: Mon, 20 Nov 2023 15:08:26 +0000 (+0000) Subject: docs/emulation: expand warning about semihosting X-Git-Tag: qemu-xen-4.20.0~398^2~7 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=ef073ebd329aecc5f31a3a9d6e355e367f5bfb99;p=qemu-xen.git 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 Signed-off-by: Alex Bennée Message-Id: <20231120150833.2552739-8-alex.bennee@linaro.org> --- diff --git a/docs/about/emulation.rst b/docs/about/emulation.rst index 0ad0b86f0d..a2eefe3f3f 100644 --- a/docs/about/emulation.rst +++ b/docs/about/emulation.rst @@ -129,8 +129,9 @@ causing most hypervisors to trap and fault on them. .. 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 ~~~~~~~~~~~