I want to upgrade my system to mitigate Spectre and Meltdown exploits.
The relevant Ubuntu page states that I need to update microcodes: "From a guest and non-hypervisor bare-metal perspective, as of the Feb 21 kernel updates, as far as we are aware, the mitigations for Spectre and Meltdown on 64-bit amd64, ppc64el and s390x are feature-complete as long as all microcode, firmware and hypervisor updates underneath the system are done. ..."
I have intel-microcode and iucode-tool installed and updated, however running dmesg | grep -i microcode and grep -i microcode /var/log/syslog* return nothing which makes me think that either the cpu microcode doesn't get updated or something else is wrong.
Packages are up to date and there have been restarts since the last update.
operating system: Lubuntu 16.04
CPU: Intel N3700 (Braswell)
enabled software repos: main, universe
enabled updates: xenial-security
Edit:
The output of grep name /proc/cpuinfo | sort -u is
model name : Intel(R) Pentium(R) CPU N3700 @ 1.60GHz
My processor is not Skylake, nor Kaby lake.
In /proc/cpuinfo hyper-threading shows up as supported, but this Intel page says it is not supported:
https://ark.intel.com/products/87261/Intel-Pentium-Processor-N3700-2M-Cache-up-to-2_40-GHz
Edit 2:
I ran sudo update-initramfs -u and rebooted. The outputs are still the same.
Output of /usr/sbin/iucode_tool -tb -lS /lib/firmware/intel-ucode/*:
/usr/sbin/iucode_tool: system has processor(s) with signature 0x000406c3
selected microcodes:
It seems that there is no updated microcode for my cpu, which is interesting since there was a selectable microcode in the Additional Drivers tab previously (late 2017); now, there isn't.
Edit 3:
Output of apt list --installed | grep intel-microcode:
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
intel-microcode/xenial-security,now 3.20180108.0+really20170707ubuntu16.04.1 amd64 [installed]
Edit 4:
Now I understand that there is no update for the cpu microcode, which means that the original problem is solved, and I will leave it as it is.
However, dmesg and journalctl -b should still output lines about microcode version, I believe.
I also noticed that these boot logs start at "5" instead of the tipical 1 or 0, and that there is a repeating error message which makes them truncated (dmesg says nothing about truncation, but journalctl says there are 371635 missed kernel messages, see below). I will ignore this for now.
March 19 06:36:40 NN systemd-journald[266]: Runtime journal (/run/log/journal/) is 8.0M, max 78.9M, 70.9M free.
March 19 06:36:40 NN systemd-journald[266]: Missed 371635 kernel messages
March 19 06:36:40 NN kernel: handle_bad_irq+0x0/0x230
March 19 06:36:40 NN kernel: ->irq_data.chip(): ffffffffbb172c40,
March 19 06:36:40 NN kernel: chv_gpio_irqchip+0x0/0x120
March 19 06:36:40 NN kernel: ->action(): (null)
March 19 06:36:40 NN kernel: IRQ_NOPROBE set
March 19 06:36:40 NN kernel: irq 115, desc: ffff9b91f5df8200, depth: 1, count: 0, unhandled: 0
March 19 06:36:40 NN kernel: ->handle_irq(): ffffffffb9ee8f70,
March 19 06:36:40 NN kernel: handle_bad_irq+0x0/0x230
March 19 06:36:40 NN kernel: ->irq_data.chip(): ffffffffbb172c40,
March 19 06:36:40 NN kernel: chv_gpio_irqchip+0x0/0x120
March 19 06:36:40 NN kernel: ->action(): (null)
March 19 06:36:40 NN kernel: IRQ_NOPROBE set
March 19 06:36:40 NN kernel: irq 115, desc: ffff9b91f5df8200, depth: 1, count: 0, unhandled: 0
March 19 06:36:40 NN kernel: ->handle_irq(): ffffffffb9ee8f70,
March 19 06:36:40 NN kernel: handle_bad_irq+0x0/0x230
March 19 06:36:40 NN kernel: ->irq_data.chip(): ffffffffbb172c40,
March 19 06:36:40 NN kernel: chv_gpio_irqchip+0x0/0x120
March 19 06:36:40 NN kernel: ->action(): (null)
March 19 06:36:40 NN kernel: IRQ_NOPROBE set
March 19 06:36:40 NN kernel: irq 115, desc: ffff9b91f5df8200, depth: 1, count: 0, unhandled: 0
March 19 06:36:40 NN kernel: ->handle_irq(): ffffffffb9ee8f70,
March 19 06:36:40 NN kernel: handle_bad_irq+0x0/0x230
March 19 06:36:40 NN kernel: ->irq_data.chip(): ffffffffbb172c40,
March 19 06:36:40 NN kernel: chv_gpio_irqchip+0x0/0x120
