From fac862ffa605f6fa41f52033b27346d26a96bea5 Mon Sep 17 00:00:00 2001 From: Eduardo Habkost Date: Thu, 12 Nov 2015 15:29:54 -0200 Subject: osdep: Change default value of qemu_hw_version() to "2.5+" There are two issues with qemu_hw_version() today: 1) If a machine has hw_version set, the value returned by it is not very useful, because it is not the actual QEMU version. 2) If a machine does't set hw_version, the return value of qemu_hw_version() is broken, because it will change when upgrading QEMU. For those reasons, using qemu_hw_version() is strongly discouraged, and should be used only in code that used QEMU_VERSION in the past and needs to keep compatibility. To fix (2), instead of making every machine broken by default unless they set hw_version, make qemu_hw_version() simply return "2.5+" if qemu_set_hw_version() is not called. Suggested-by: Michael S. Tsirkin Signed-off-by: Eduardo Habkost Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- include/hw/boards.h | 5 +++++ include/qemu/osdep.h | 4 ++++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/hw/boards.h b/include/hw/boards.h index 24eb6f0..5da4fb0 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -51,6 +51,11 @@ bool machine_mem_merge(MachineState *machine); * used to provide @cpu_index to socket number mapping, allowing * a machine to group CPU threads belonging to the same socket/package * Returns: socket number given cpu_index belongs to. + * @hw_version: + * Value of QEMU_VERSION when the machine was added to QEMU. + * Set only by old machines because they need to keep + * compatibility on code that exposed QEMU_VERSION to guests in + * the past (and now use qemu_hw_version()). */ struct MachineClass { /*< private >*/ diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index 861d84b..84e84ac 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -256,6 +256,10 @@ static inline void qemu_timersub(const struct timeval *val1, void qemu_set_cloexec(int fd); +/* QEMU "hardware version" setting. Used to replace code that exposed + * QEMU_VERSION to guests in the past and need to keep compatibilty. + * Do not use qemu_hw_version() in new code. + */ void qemu_set_hw_version(const char *); const char *qemu_hw_version(void); -- cgit v1.1