AMD issued an advisory that having fTPM enabled and utilizing certain functionality can cause stuttering in the OS. This was a Windows specific problem initially, but commit b006c439d58db ("hwrng: core - start hwrng kthread also for untrusted sources") exposed it for Linux as well. This issue has been fixed by newer fTPM firmware, but not many system designers have rolled out the fix, so to avoid triggering it check AMD's fTPM implementation version to decide whether to register the fTPM RNG. As this regression was reported by many users and escalated by Thorsten as tracking the regressions it's being sent directly to Linus to try to catch 6.2 release. Mario Limonciello (1): tpm: disable hwrng for fTPM on some AMD designs drivers/char/tpm/tpm-chip.c | 62 ++++++++++++++++++++++++++++++- drivers/char/tpm/tpm.h | 73 +++++++++++++++++++++++++++++++++++++ 2 files changed, 134 insertions(+), 1 deletion(-) -- 2.25.1