[PATCH v2] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-07-02 Thread Alexandre Chartre
lable (and enabled by default) on older versions of i440fx/q35 machines. Suggested-by: Zhao Liu Resolves: https://gitlab.com/qemu-project/qemu/-/issues/3001 Signed-off-by: Alexandre Chartre --- hw/i386/pc.c | 4 +++- target/i386/cpu.c | 18 ++ target/i386/cpu.h

Re: [PATCH] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-07-02 Thread Alexandre Chartre
On 7/2/25 07:01, Zhao Liu wrote: Thanks Igor for looking here and thanks Konrad's explanation. On 7/1/2025 6:26 PM, Zhao Liu wrote: unless it was explicitly requested by the user. But this could still break Windows, just like issue #3001, which enables arch-capabilities for EPYC-Genoa. This

Re: [PATCH] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-07-01 Thread Alexandre Chartre
On 7/1/25 12:26, Zhao Liu wrote: (I'd like to CC Sean again to discuss the possibility of user space removing arch-capabilities completely for AMD) On Mon, Jun 30, 2025 at 03:30:25PM +0200, Alexandre Chartre wrote: Date: Mon, 30 Jun 2025 15:30:25 +0200 From: Alexandre Chartre Su

Re: [PATCH] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-07-01 Thread Alexandre Chartre
On 7/1/25 13:12, Xiaoyao Li wrote: On 7/1/2025 6:26 PM, Zhao Liu wrote: unless it was explicitly requested by the user. But this could still break Windows, just like issue #3001, which enables arch-capabilities for EPYC-Genoa. This fact shows that even explicitly turning on arch-capabilities

Re: [PATCH] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-07-01 Thread Alexandre Chartre
On 7/1/25 10:23, Xiaoyao Li wrote: On 6/30/2025 9:30 PM, Alexandre Chartre wrote: KVM emulates the ARCH_CAPABILITIES on x86 for both Intel and AMD cpus, although the IA32_ARCH_CAPABILITIES MSR is an Intel-specific MSR and it makes no sense to emulate it on AMD. As a consequence, VMs created

[PATCH] i386/cpu: ARCH_CAPABILITIES should not be advertised on AMD

2025-06-30 Thread Alexandre Chartre
vided by explicitly setting arch-capabilities=on. Signed-off-by: Alexandre Chartre --- target/i386/cpu.c | 14 ++ 1 file changed, 14 insertions(+) diff --git a/target/i386/cpu.c b/target/i386/cpu.c index 0d35e95430..7e136c48df 100644 --- a/target/i386/cpu.c +++ b/target/i386/