tcg_region_init() calls one of qemu_mprotect_rwx(),
qemu_mprotect_rw(), and mprotect(), then reports failure with
error_setg_errno(&error_fatal, errno, ...).
The use of &error_fatal is undesirable. qapi/error.h advises:
* Please don't error_setg(&error_fatal, ...), use error_report() and
* exit(), because that's more obvious.
The use of errno is wrong. qemu_mprotect_rwx() and qemu_mprotect_rw()
wrap around qemu_mprotect__osdep(). qemu_mprotect__osdep() calls
mprotect() on POSIX, VirtualProtect() on Windows, and reports failure
with error_report(). VirtualProtect() doesn't set errno. mprotect()
does, but error_report() may clobber it.
Fix tcg_region_init() to report errors only when it calls mprotect(),
and rely on qemu_mprotect_rwx()'s and qemu_mprotect_rw()'s error
reporting otherwise. Use error_report(), not error_setg().
Fixes: 22c6a9938f (tcg: Merge buffer protection and guard page protection)
Fixes: 6bc144237a (tcg: Use Error with alloc_code_gen_buffer)
Cc: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250923091000.3180122-3-armbru@redhat.com>
Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Markus Armbruster
82b5e6cc30