On Mon, 27 May 2024 11:13:33 +0800
Chuang Xu <xuchuangxc...@bytedance.com> wrote:
> When QEMU is started with:
> -cpu host,host-cache-info=on,l3-cache=off \
> -smp 2,sockets=1,dies=1,cores=1,threads=2
> Guest can't acquire maximum number of addressable IDs for processor cores in
> the physical package from CPUID[04H].
please add commit message, what you are actually seeing
and expected values as well.
And if guest complains about it also include related dmesg output.
> This bug was introduced in commit d7caf13b5fcf742e5680c1d3448ba070fc811644.
> Fix it by changing the judgement condition to a >= 1.
>
> Signed-off-by: Chuang Xu <xuchuangxc...@bytedance.com>
> Signed-off-by: Guixiong Wei <weiguixi...@bytedance.com>
> Signed-off-by: Yipeng Yin <yinyip...@bytedance.com>
> ---
> target/i386/cpu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
> index cd16cb893d..0369c01153 100644
> --- a/target/i386/cpu.c
> +++ b/target/i386/cpu.c
> @@ -6097,7 +6097,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t index,
> uint32_t count,
> if (*eax & 31) {
> int host_vcpus_per_cache = 1 + ((*eax & 0x3FFC000) >> 14);
> int vcpus_per_socket = cs->nr_cores * cs->nr_threads;
in light of dies and recent modules shouldn't we also account for them here?
> - if (cs->nr_cores > 1) {
> + if (cs->nr_cores >= 1) {
> *eax &= ~0xFC000000;
> *eax |= (pow2ceil(cs->nr_cores) - 1) << 26;
> }
above and also following condition
if (host_vcpus_per_cache > vcpus_per_socket) {
...
*eax |= (pow2ceil(vcpus_per_socket) - 1) << 14;
Makes me think, do we really have to have both conditionals,
Why not just drop conditions and always encode both values
to ones configured on '-smp' CLI?
