Patch "powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()" has been added to the 4.14-stable tree

[gregkh at linuxfoundation.org]

This is a note to let you know that I've just added the patch titled

    powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable at vger.kernel.org> know about it.


>From foo at baz Sun May 27 15:47:18 CEST 2018
From: Michael Ellerman <mpe at ellerman.id.au>
Date: Sat, 26 May 2018 14:27:42 +1000
Subject: powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()
To: greg at kroah.com
Cc: stable at vger.kernel.org, tglx at linutronix.de, linuxppc-dev at ozlabs.org
Message-ID: <20180526042749.5324-17-mpe at ellerman.id.au>

From: Michael Ellerman <mpe at ellerman.id.au>

commit 2e4a16161fcd324b1f9bf6cb6856529f7eaf0689 upstream.

Now that we have the security flags we can simplify the code in
pseries_setup_rfi_flush() because the security flags have pessimistic
defaults.

Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |   27 ++++++++++++---------------
 1 file changed, 12 insertions(+), 15 deletions(-)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -501,30 +501,27 @@ void pseries_setup_rfi_flush(void)
 	bool enable;
 	long rc;
 
-	/* Enable by default */
-	enable = true;
-	types = L1D_FLUSH_FALLBACK;
-
 	rc = plpar_get_cpu_characteristics(&result);
-	if (rc == H_SUCCESS) {
+	if (rc == H_SUCCESS)
 		init_cpu_char_feature_flags(&result);
 
-		if (result.character & H_CPU_CHAR_L1D_FLUSH_TRIG2)
-			types |= L1D_FLUSH_MTTRIG;
-		if (result.character & H_CPU_CHAR_L1D_FLUSH_ORI30)
-			types |= L1D_FLUSH_ORI;
-
-		if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
-		    (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
-			enable = false;
-	}
-
 	/*
 	 * We're the guest so this doesn't apply to us, clear it to simplify
 	 * handling of it elsewhere.
 	 */
 	security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
 
+	types = L1D_FLUSH_FALLBACK;
+
+	if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2))
+		types |= L1D_FLUSH_MTTRIG;
+
+	if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30))
+		types |= L1D_FLUSH_ORI;
+
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
+		 security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR);
+
 	setup_rfi_flush(types, enable);
 }
 


Patches currently in stable-queue which might be from mpe at ellerman.id.au are

queue-4.14/powerpc-64s-clear-pcr-on-boot.patch
queue-4.14/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.14/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.14/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.14/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.14/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.14/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.14/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.14/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.14/powerpc-move-default-security-feature-flags.patch
queue-4.14/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.14/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.14/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.14/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.14/powerpc-64s-improve-rfi-l1-d-cache-flush-fallback.patch
queue-4.14/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.14/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.14/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.14/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.14/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.14/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.14/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.14/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.14/powerpc-64s-wire-up-cpu_show_spectre_v2.patch