Re: [Xen-devel] [PATCH] x86/spec-ctrl: Fix the parsing of xpti= on fixed Intel hardware

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 23.07.18 at 16:22, <jgross@xxxxxxxx> wrote:
> On 23/07/18 15:48, Andrew Cooper wrote:
>> The calls to xpti_init_default() in parse_xpti() are buggy.  The CPUID data
>> hasn't been fetched that early, and boot_cpu_has(X86_FEATURE_ARCH_CAPS) will
>> always evaluate false.
>> 
>> As a result, the default case won't disable XPTI on Intel hardware which
>> advertises ARCH_CAPABILITIES_RDCL_NO.
>> 
>> Simplify parse_xpti() to solely the setting of opt_xpti according to the
>> passed string, and have init_speculation_mitigations() call
>> xpti_init_default() if appropiate.  Drop the force parameter, and pass caps
>> instead, to avoid redundant re-reading of MSR_ARCH_CAPS.
>> 
>> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> 
> Reviewed-by: Juergen Gross <jgross@xxxxxxxx>

Acked-by: Jan Beulich <jbeulich@xxxxxxxx>



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel