On 7/11/2025 3:46 AM, Babu Moger wrote:
Transient Scheduler Attacks (TSA) are new speculative side channel attacks related to the execution timing of instructions under specific microarchitectural conditions. In some cases, an attacker may be able to use this timing information to infer data from other contexts, resulting in information leakage. AMD has identified two sub-variants two variants of TSA. CPUID Fn8000_0021 ECX[1] (TSA_SQ_NO). If this bit is 1, the CPU is not vulnerable to TSA-SQ. CPUID Fn8000_0021 ECX[2] (TSA_L1_NO). If this bit is 1, the CPU is not vulnerable to TSA-L1. Add the new feature word FEAT_8000_0021_ECX and corresponding bits to detect TSA variants. Link: https://www.amd.com/content/dam/amd/en/documents/resources/bulletin/technical-guidance-for-mitigating-transient-scheduler-attacks.pdf Co-developed-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
Reviewed-by: Xiaoyao Li <xiaoyao.li@xxxxxxxxx>
