Commit c18956e6 authored by Laurent Dufour's avatar Laurent Dufour Committed by Michael Ellerman
Browse files

powerpc/pseries: Fix update of LPAR security flavor after LPM 



After LPM, when migrating from a system with security mitigation enabled
to a system with mitigation disabled, the security flavor exposed in
/proc is not correctly set back to 0.

Do not assume the value of the security flavor is set to 0 when entering
init_cpu_char_feature_flags(), so when called after a LPM, the value is
set correctly even if the mitigation are not turned off.

Fixes: 6ce56e1a ("powerpc/pseries: export LPAR security flavor in lparcfg")
Cc: stable@vger.kernel.org # v5.13+
Signed-off-by: default avatarLaurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210805152308.33988-1-ldufour@linux.ibm.com
parent 82414615

arch/powerpc/platforms/pseries/setup.c

+3 −2
Original line number Diff line number Diff line
@@ -539,9 +539,10 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result) 
	 * H_CPU_BEHAV_FAVOUR_SECURITY_H could be set only if

	 * H_CPU_BEHAV_FAVOUR_SECURITY is.

	 */

	if (!(result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY))

	if (!(result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)) {

		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);

	else if (result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY_H)

		pseries_security_flavor = 0;

	} else if (result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY_H)

		pseries_security_flavor = 1;

	else

		pseries_security_flavor = 2;