[PATCH 4/4] powerpc/powernv: Remove POWER9 PVR version check for entry and uaccess flushes

Nicholas Piggin npiggin at gmail.com
Mon May 3 23:02:43 AEST 2021


These aren't necessarily POWER9 only, and it's not to say some new
vulnerability may not get discovered on other processors for which
we would like the flexibility of having the workaround enabled by
firmware.

Remove the restriction that they only apply to POWER9.

Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
 arch/powerpc/platforms/powernv/setup.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index a8db3f153063..6ec67223f8c7 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -122,15 +122,6 @@ static void pnv_setup_security_mitigations(void)
 			type = L1D_FLUSH_ORI;
 	}
 
-	/*
-	 * If we are non-Power9 bare metal, we don't need to flush on kernel
-	 * entry or after user access: they fix a P9 specific vulnerability.
-	 */
-	if (!pvr_version_is(PVR_POWER9)) {
-		security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
-		security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
-	}
-
 	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
 		 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)   || \
 		  security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
-- 
2.23.0



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