On Thursday, 7 June 2018 08:37:41 BST zless wrote: > Hello, > > I just finished installing kernel 4.14.48 on two > Intel laptops and I have different results for > > /sys/devices/system/cpu/vulnerabilities/spec_store_bypass > > On one of them it looks nice: > "Mitigation: Speculative Store Bypass disabled via prctl and seccomp" > but on the other it still says "Vulnerable". > > Any idea on what might influence this? The kernel configs are fairly > similar, the only thing that's different is the microcode, which is from > 2017 for the "vulnerable" one. > > Thanks
I would think it is cause by the microcode. I have two really old Intel laptops and despite announcements to the contrary I noticed the latest (stable) sys-firmware/intel-microcode-20180527-r1 changed the Intel microcode version being loaded on both PCs, after I rebuilt the kernel (4.9.95) to incorporate it (no initrd on either of them). I see this for Spectre V2 which now includes IBPB and IBRS_FW: $ dmesg | grep Spectre [ 0.011385] Spectre V2 : Mitigation: Full generic retpoline [ 0.011507] Spectre V2 : Spectre v2 mitigation: Enabling Indirect Branch Prediction Barrier [ 0.011645] Spectre V2 : Enabling Restricted Speculation for firmware calls After you updated sys-firmware/intel-microcode did you rebuild and reboot the *rebuilt* kernel on both PCs? PS. For good measure I ran make clean first, but I'm not sure if this affects the firmware. -- Regards, Mick
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