On Thu, Jul 14, 2022 at 09:11:18PM -0300, Thadeu Lima de Souza Cascardo wrote:
On Thu, Jul 14, 2022 at 04:15:35PM -0700, Pawan Gupta wrote:
IBRS mitigation for spectre_v2 forces write to MSR_IA32_SPEC_CTRL at
every kernel entry/exit. On Enhanced IBRS parts setting
MSR_IA32_SPEC_CTRL[IBRS] only once at boot is sufficient. MSR writes at
every kernel entry/exit incur unnecessary performance loss.
When Enhanced IBRS feature is present, print a warning about this
unnecessary performance loss.
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx>
Reviewed-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Thanks for the review.
Pawan
