[MODERATED] Re: Re: [PATCH v7 04/10] TAAv7 4

On Tue, Oct 22, 2019 at 10:44:52AM -0700, speck for Pawan Gupta wrote:
> There is a small problem with this, it will set
> 
> 	taa_mitigation = TAA_MITIGATION_TSX_DISABLE;
> 
> when there is no X86_BUG_TAA.

And?

When the CPU doesn't support TSX, then this practically is "Mitigation:
TSX disabled" because, well, TSX *is* disabled.

Also, from all the possible settings:

        [TAA_MITIGATION_OFF]            = "Vulnerable",
        [TAA_MITIGATION_UCODE_NEEDED]   = "Vulnerable: Clear CPU buffers attempted, no microcode",
        [TAA_MITIGATION_VERW]           = "Mitigation: Clear CPU buffers",
        [TAA_MITIGATION_TSX_DISABLE]    = "Mitigation: TSX disabled",

TAA_MITIGATION_TSX_DISABLE is the one that fits best for the !RTM case,
no?

> goto will cause it to differ from other mitigations that don't print
> individual mitigation status when mitigations are turned off globally
> (when cpu_mitigations_off() is true).

Well, I'd prefer to have a confirmation in dmesg that mitigations were
off but we have that in sysfs already. And the other mitigations don't
print anything, as you say, so yeah, I guess let's not fall out of line
here.

Thx.

-- 
Regards/Gruss,
    Boris.

SUSE Software Solutions Germany GmbH, GF: Felix Imendörffer, HRB 36809, AG Nürnberg
--