On 6/24/25 17:16, Yazen Ghannam wrote:
The __mcheck_cpu_init_early() function was introduced so that some vendor-specific features are detected before the first MCA polling event done in __mcheck_cpu_init_generic(). Currently, __mcheck_cpu_init_early() is only used on AMD-based systems and additional code will be needed to support various system configurations. However, the current and future vendor-specific code should be done during vendor init. This keeps all the vendor code in a common location and simplifies the generic init flow. Move all the __mcheck_cpu_init_early() code into mce_amd_feature_init(). Also, move __mcheck_cpu_init_generic() after __mcheck_cpu_init_prepare_banks() so that MCA is enabled after the first MCA polling event. Additionally, this brings the MCA init flow closer to what is described in the x86 docs. The AMD PPRs say "The operating system must initialize the MCA_CONFIG registers prior to initialization of the MCA_CTL registers. The MCA_CTL registers must be initialized prior to enabling the error reporting banks in MCG_CTL". However, the Intel SDM "Machine-Check Initialization Pseudocode" says MCG_CTL first then MCi_CTL. But both agree that CR4.MCE should be set last. Reviewed-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx> Tested-by: Tony Luck <tony.luck@xxxxxxxxx> Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx> Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
IMO the change which moves __mcheck_cpu_init_generic should be in a separate patch so that in the changelog it's abundantly clear that it's a "world switch" function and its invocation timing is important.
<snip> In any case: Reviewed-by: Nikolay Borisov <nik.borisov@xxxxxxxx>
