diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-06-05 10:55:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-06-05 10:55:23 -0700 |
| commit | 9784edd73a08ea08d0ce5606e1f0f729df688c59 (patch) | |
| tree | a9247155727c093f98a62af876a476db1a69219f /arch/x86/Kconfig | |
| parent | a925128092d8dd5c2ea8644e1dddd510b7ebc9c7 (diff) | |
| parent | 0c0fe08c76485fe0178ebb0fa1a2052c727abe94 (diff) | |
Merge tag 'x86-microcode-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode updates from Thomas Gleixner:
- Disable late microcode loading by default. Unless the HW people get
their act together and provide a required minimum version in the
microcode header for making a halfways informed decision its just
lottery and broken.
- Warn and taint the kernel when microcode is loaded late
- Remove the old unused microcode loader interface
- Remove a redundant perf callback from the microcode loader
* tag 'x86-microcode-2022-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/microcode: Remove unnecessary perf callback
x86/microcode: Taint and warn on late loading
x86/microcode: Default-disable late loading
x86/microcode: Rip out the OLD_INTERFACE
Diffstat (limited to 'arch/x86/Kconfig')
| -rw-r--r-- | arch/x86/Kconfig | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7df2a9ef3662..9783ebc4e021 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1358,17 +1358,16 @@ config MICROCODE_AMD If you select this option, microcode patch loading support for AMD processors will be enabled. -config MICROCODE_OLD_INTERFACE - bool "Ancient loading interface (DEPRECATED)" +config MICROCODE_LATE_LOADING + bool "Late microcode loading (DANGEROUS)" default n depends on MICROCODE help - DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface - which was used by userspace tools like iucode_tool and microcode.ctl. - It is inadequate because it runs too late to be able to properly - load microcode on a machine and it needs special tools. Instead, you - should've switched to the early loading method with the initrd or - builtin microcode by now: Documentation/x86/microcode.rst + Loading microcode late, when the system is up and executing instructions + is a tricky business and should be avoided if possible. Just the sequence + of synchronizing all cores and SMT threads is one fragile dance which does + not guarantee that cores might not softlock after the loading. Therefore, + use this at your own risk. Late loading taints the kernel too. config X86_MSR tristate "/dev/cpu/*/msr - Model-specific register support" |