On 6/6/24 16:08, Zhao Liu wrote:
Currently, the Q35 supports up to 4096 vCPUs (since v9.0), but for TCG
cases, if x2APIC is not actively enabled to boot more than 255 vCPUs (
e.g., qemu-system-i386 -M pc-q35-9.0 -smp 666), the following error is
reported:

Unexpected error in apic_common_set_id() at ../hw/intc/apic_common.c:449:
qemu-system-i386: APIC ID 255 requires x2APIC feature in CPU
Aborted (core dumped)

This error can be resolved by setting x2apic=on in -cpu. In order to
better help users deal with this scenario, add the error hint to
instruct users on how to enable the x2apic feature.

Why not automatically set x2apic=on in this case instead?

Then, the error
report becomes the following:

Unexpected error in apic_common_set_id() at ../hw/intc/apic_common.c:448:
qemu-system-i386: APIC ID 255 requires x2APIC feature in CPU
Try x2apic=on in -cpu.
Aborted (core dumped)

Note since @errp is &error_abort, error_append_hint() can't be applied
on @errp. And in order to separate the exact error message from the
(perhaps effectively) hint, adding a hint via error_append_hint() is
also necessary. Therefore, introduce @local_error in
apic_common_set_id() to handle both the error message and the error
hint.

Suggested-by: Philippe Mathieu-Daudé <phi...@linaro.org>
Signed-off-by: Zhao Liu <zhao1....@intel.com>
---
  hw/intc/apic_common.c | 7 ++++++-
  1 file changed, 6 insertions(+), 1 deletion(-)

Reviewed-by: Philippe Mathieu-Daudé <phi...@linaro.org>


Reply via email to