[PATCH stable 4.9 00/23] powerpc backports for 4.9

[PATCH stable 4.9 00/23] powerpc backports for 4.9

[Michael Ellerman]

Hi Greg,

Please queue up this series of patches for 4.9 if you have no objections.

The first one is not a backport but a fix for a previous backport.

cheers

Mauricio Faria de Oliveira (4):
  powerpc/rfi-flush: Differentiate enabled and patched flush types
  powerpc/pseries: Fix clearing of security feature flags
  powerpc: Move default security feature flags
  powerpc/pseries: Restore default security feature flags on setup

Michael Ellerman (18):
  powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdef
  powerpc/pseries: Support firmware disable of RFI flush
  powerpc/powernv: Support firmware disable of RFI flush
  powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs
    code
  powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again
  powerpc/rfi-flush: Always enable fallback flush on pseries
  powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration
  powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags
  powerpc: Add security feature flags for Spectre/Meltdown
  powerpc/pseries: Set or clear security feature flags
  powerpc/powernv: Set or clear security feature flags
  powerpc/64s: Move cpu_show_meltdown()
  powerpc/64s: Enhance the information in cpu_show_meltdown()
  powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()
  powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()
  powerpc/64s: Wire up cpu_show_spectre_v1()
  powerpc/64s: Wire up cpu_show_spectre_v2()
  powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()

Nicholas Piggin (1):
  powerpc/64s: Add support for a store forwarding barrier at kernel
    entry/exit

 arch/powerpc/include/asm/exception-64s.h     |  29 ++++
 arch/powerpc/include/asm/feature-fixups.h    |  19 +++
 arch/powerpc/include/asm/hvcall.h            |   3 +
 arch/powerpc/include/asm/security_features.h |  85 ++++++++++
 arch/powerpc/include/asm/setup.h             |   2 +-
 arch/powerpc/kernel/Makefile                 |   2 +-
 arch/powerpc/kernel/exceptions-64s.S         |  16 +-
 arch/powerpc/kernel/security.c               | 237 +++++++++++++++++++++++++++
 arch/powerpc/kernel/setup_64.c               |  37 ++---
 arch/powerpc/kernel/vmlinux.lds.S            |  14 ++
 arch/powerpc/lib/feature-fixups.c            | 124 +++++++++++++-
 arch/powerpc/platforms/powernv/setup.c       |  92 ++++++++---
 arch/powerpc/platforms/pseries/mobility.c    |   3 +
 arch/powerpc/platforms/pseries/pseries.h     |   2 +
 arch/powerpc/platforms/pseries/setup.c       |  81 +++++++--
 15 files changed, 679 insertions(+), 67 deletions(-)
 create mode 100644 arch/powerpc/include/asm/security_features.h
 create mode 100644 arch/powerpc/kernel/security.c

-- 
2.14.1

[PATCH stable 4.9 01/23] powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdef

[Michael Ellerman]

The backport of the RFI flush support, done by me, has a minor bug in
that the code is inside an #ifdef CONFIG_HARDLOCKUP_DETECTOR, which is
incorrect.

This doesn't matter with common configs because we enable
HARDLOCKUP_DETECTOR, but with future patches it will break the build.
So fix it.

Fixes: c3b82ebee6e0 ("powerpc/64s: Add support for RFI flush of L1-D cache")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/setup_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 5243501d95ef..1746639c4dcd 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -679,6 +679,7 @@ static int __init disable_hardlockup_detector(void)
 	return 0;
 }
 early_initcall(disable_hardlockup_detector);
+#endif /* CONFIG_HARDLOCKUP_DETECTOR */
 
 #ifdef CONFIG_PPC_BOOK3S_64
 static enum l1d_flush_type enabled_flush_types;
@@ -806,4 +807,3 @@ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, cha
 	return sprintf(buf, "Vulnerable\n");
 }
 #endif /* CONFIG_PPC_BOOK3S_64 */
-#endif
-- 
2.14.1

Patch "powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdef" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdef

to the 4.9-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-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:46 +1000
Subject: powerpc/rfi-flush: Move out of HARDLOCKUP_DETECTOR #ifdef
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-2-mpe@ellerman.id.au>

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

The backport of the RFI flush support, done by me, has a minor bug in
that the code is inside an #ifdef CONFIG_HARDLOCKUP_DETECTOR, which is
incorrect.

This doesn't matter with common configs because we enable
HARDLOCKUP_DETECTOR, but with future patches it will break the build.
So fix it.

Fixes: c3b82ebee6e0 ("powerpc/64s: Add support for RFI flush of L1-D cache")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/setup_64.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -679,6 +679,7 @@ static int __init disable_hardlockup_det
 	return 0;
 }
 early_initcall(disable_hardlockup_detector);
+#endif /* CONFIG_HARDLOCKUP_DETECTOR */
 
 #ifdef CONFIG_PPC_BOOK3S_64
 static enum l1d_flush_type enabled_flush_types;
@@ -806,4 +807,3 @@ ssize_t cpu_show_meltdown(struct device
 	return sprintf(buf, "Vulnerable\n");
 }
 #endif /* CONFIG_PPC_BOOK3S_64 */
-#endif


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 02/23] powerpc/pseries: Support firmware disable of RFI flush

[Michael Ellerman]

commit 582605a429e20ae68fd0b041b2e840af296edd08 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 8989d56878a7 ("powerpc/pseries: Query hypervisor for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 1845fc611912..0982e13b2942 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -473,7 +473,8 @@ static void pseries_setup_rfi_flush(void)
 		if (types == L1D_FLUSH_NONE)
 			types = L1D_FLUSH_FALLBACK;
 
-		if (!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))
+		if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
+		    (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
 			enable = false;
 	} else {
 		/* Default to fallback if case hcall is not available */
-- 
2.14.1

Patch "powerpc/pseries: Support firmware disable of RFI flush" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/pseries: Support firmware disable of RFI flush

to the 4.9-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-support-firmware-disable-of-rfi-flush.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:47 +1000
Subject: powerpc/pseries: Support firmware disable of RFI flush
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-3-mpe@ellerman.id.au>

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

commit 582605a429e20ae68fd0b041b2e840af296edd08 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 8989d56878a7 ("powerpc/pseries: Query hypervisor for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -473,7 +473,8 @@ static void pseries_setup_rfi_flush(void
 		if (types == L1D_FLUSH_NONE)
 			types = L1D_FLUSH_FALLBACK;
 
-		if (!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))
+		if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
+		    (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
 			enable = false;
 	} else {
 		/* Default to fallback if case hcall is not available */


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 03/23] powerpc/powernv: Support firmware disable of RFI flush

[Michael Ellerman]

commit eb0a2d2620ae431c543963c8c7f08f597366fc60 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 6e032b350cd1 ("powerpc/powernv: Check device-tree for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 6f8b4c19373a..4764bc91570c 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -79,6 +79,10 @@ static void pnv_setup_rfi_flush(void)
 		if (np && of_property_read_bool(np, "disabled"))
 			enable--;
 
+		np = of_get_child_by_name(fw_features, "speculation-policy-favor-security");
+		if (np && of_property_read_bool(np, "disabled"))
+			enable = 0;
+
 		of_node_put(np);
 		of_node_put(fw_features);
 	}
-- 
2.14.1

Patch "powerpc/powernv: Support firmware disable of RFI flush" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/powernv: Support firmware disable of RFI flush

to the 4.9-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-powernv-support-firmware-disable-of-rfi-flush.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:48 +1000
Subject: powerpc/powernv: Support firmware disable of RFI flush
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-4-mpe@ellerman.id.au>

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

commit eb0a2d2620ae431c543963c8c7f08f597366fc60 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 6e032b350cd1 ("powerpc/powernv: Check device-tree for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/powernv/setup.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -79,6 +79,10 @@ static void pnv_setup_rfi_flush(void)
 		if (np && of_property_read_bool(np, "disabled"))
 			enable--;
 
+		np = of_get_child_by_name(fw_features, "speculation-policy-favor-security");
+		if (np && of_property_read_bool(np, "disabled"))
+			enable = 0;
+
 		of_node_put(np);
 		of_node_put(fw_features);
 	}


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 04/23] powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code

[Michael Ellerman]

commit 1e2a9fc7496955faacbbed49461d611b704a7505 upstream.

rfi_flush_enable() includes a check to see if we're already
enabled (or disabled), and in that case does nothing.

But that means calling setup_rfi_flush() a 2nd time doesn't actually
work, which is a bit confusing.

Move that check into the debugfs code, where it really belongs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/setup_64.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 1746639c4dcd..e6bed89a98ed 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -717,9 +717,6 @@ static void do_nothing(void *unused)
 
 void rfi_flush_enable(bool enable)
 {
-	if (rfi_flush == enable)
-		return;
-
 	if (enable) {
 		do_rfi_flush_fixups(enabled_flush_types);
 		on_each_cpu(do_nothing, NULL, 1);
@@ -773,13 +770,19 @@ void __init setup_rfi_flush(enum l1d_flush_type types, bool enable)
 #ifdef CONFIG_DEBUG_FS
 static int rfi_flush_set(void *data, u64 val)
 {
+	bool enable;
+
 	if (val == 1)
-		rfi_flush_enable(true);
+		enable = true;
 	else if (val == 0)
-		rfi_flush_enable(false);
+		enable = false;
 	else
 		return -EINVAL;
 
+	/* Only do anything if we're changing state */
+	if (enable != rfi_flush)
+		rfi_flush_enable(enable);
+
 	return 0;
 }
 
-- 
2.14.1

Patch "powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code

to the 4.9-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-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:49 +1000
Subject: powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-5-mpe@ellerman.id.au>

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

commit 1e2a9fc7496955faacbbed49461d611b704a7505 upstream.

rfi_flush_enable() includes a check to see if we're already
enabled (or disabled), and in that case does nothing.

But that means calling setup_rfi_flush() a 2nd time doesn't actually
work, which is a bit confusing.

Move that check into the debugfs code, where it really belongs.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/setup_64.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -717,9 +717,6 @@ static void do_nothing(void *unused)
 
 void rfi_flush_enable(bool enable)
 {
-	if (rfi_flush == enable)
-		return;
-
 	if (enable) {
 		do_rfi_flush_fixups(enabled_flush_types);
 		on_each_cpu(do_nothing, NULL, 1);
@@ -773,13 +770,19 @@ void __init setup_rfi_flush(enum l1d_flu
 #ifdef CONFIG_DEBUG_FS
 static int rfi_flush_set(void *data, u64 val)
 {
+	bool enable;
+
 	if (val == 1)
-		rfi_flush_enable(true);
+		enable = true;
 	else if (val == 0)
-		rfi_flush_enable(false);
+		enable = false;
 	else
 		return -EINVAL;
 
+	/* Only do anything if we're changing state */
+	if (enable != rfi_flush)
+		rfi_flush_enable(enable);
+
 	return 0;
 }
 


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 05/23] powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again

[Michael Ellerman]

commit abf110f3e1cea40f5ea15e85f5d67c39c14568a7 upstream.

For PowerVM migration we want to be able to call setup_rfi_flush()
again after we've migrated the partition.

To support that we need to check that we're not trying to allocate the
fallback flush area after memblock has gone away (i.e., boot-time only).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/setup.h | 2 +-
 arch/powerpc/kernel/setup_64.c   | 6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 6825a67cc3db..3f160cd20107 100644
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -48,7 +48,7 @@ enum l1d_flush_type {
 	L1D_FLUSH_MTTRIG	= 0x8,
 };
 
-void __init setup_rfi_flush(enum l1d_flush_type, bool enable);
+void setup_rfi_flush(enum l1d_flush_type, bool enable);
 void do_rfi_flush_fixups(enum l1d_flush_type types);
 
 #endif /* !__ASSEMBLY__ */
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index e6bed89a98ed..568793009daa 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -731,6 +731,10 @@ static void init_fallback_flush(void)
 	u64 l1d_size, limit;
 	int cpu;
 
+	/* Only allocate the fallback flush area once (at boot time). */
+	if (l1d_flush_fallback_area)
+		return;
+
 	l1d_size = ppc64_caches.dsize;
 	limit = min(safe_stack_limit(), ppc64_rma_size);
 
@@ -748,7 +752,7 @@ static void init_fallback_flush(void)
 	}
 }
 
-void __init setup_rfi_flush(enum l1d_flush_type types, bool enable)
+void setup_rfi_flush(enum l1d_flush_type types, bool enable)
 {
 	if (types & L1D_FLUSH_FALLBACK) {
 		pr_info("rfi-flush: Using fallback displacement flush\n");
-- 
2.14.1

Patch "powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again

to the 4.9-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-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:50 +1000
Subject: powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-6-mpe@ellerman.id.au>

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

commit abf110f3e1cea40f5ea15e85f5d67c39c14568a7 upstream.

For PowerVM migration we want to be able to call setup_rfi_flush()
again after we've migrated the partition.

To support that we need to check that we're not trying to allocate the
fallback flush area after memblock has gone away (i.e., boot-time only).

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/setup.h |    2 +-
 arch/powerpc/kernel/setup_64.c   |    6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -48,7 +48,7 @@ enum l1d_flush_type {
 	L1D_FLUSH_MTTRIG	= 0x8,
 };
 
-void __init setup_rfi_flush(enum l1d_flush_type, bool enable);
+void setup_rfi_flush(enum l1d_flush_type, bool enable);
 void do_rfi_flush_fixups(enum l1d_flush_type types);
 
 #endif /* !__ASSEMBLY__ */
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -731,6 +731,10 @@ static void init_fallback_flush(void)
 	u64 l1d_size, limit;
 	int cpu;
 
+	/* Only allocate the fallback flush area once (at boot time). */
+	if (l1d_flush_fallback_area)
+		return;
+
 	l1d_size = ppc64_caches.dsize;
 	limit = min(safe_stack_limit(), ppc64_rma_size);
 
@@ -748,7 +752,7 @@ static void init_fallback_flush(void)
 	}
 }
 
-void __init setup_rfi_flush(enum l1d_flush_type types, bool enable)
+void setup_rfi_flush(enum l1d_flush_type types, bool enable)
 {
 	if (types & L1D_FLUSH_FALLBACK) {
 		pr_info("rfi-flush: Using fallback displacement flush\n");


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 06/23] powerpc/rfi-flush: Always enable fallback flush on pseries

[Michael Ellerman]

commit 84749a58b6e382f109abf1e734bc4dd43c2c25bb upstream.

This ensures the fallback flush area is always allocated on pseries,
so in case a LPAR is migrated from a patched to an unpatched system,
it is possible to enable the fallback flush in the target system.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 0982e13b2942..626bf1ce1d80 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -459,26 +459,18 @@ static void pseries_setup_rfi_flush(void)
 
 	/* Enable by default */
 	enable = true;
+	types = L1D_FLUSH_FALLBACK;
 
 	rc = plpar_get_cpu_characteristics(&result);
 	if (rc == H_SUCCESS) {
-		types = L1D_FLUSH_NONE;
-
 		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;
 
-		/* Use fallback if nothing set in hcall */
-		if (types == L1D_FLUSH_NONE)
-			types = L1D_FLUSH_FALLBACK;
-
 		if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
 		    (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
 			enable = false;
-	} else {
-		/* Default to fallback if case hcall is not available */
-		types = L1D_FLUSH_FALLBACK;
 	}
 
 	setup_rfi_flush(types, enable);
-- 
2.14.1

Patch "powerpc/rfi-flush: Always enable fallback flush on pseries" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Always enable fallback flush on pseries

to the 4.9-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-rfi-flush-always-enable-fallback-flush-on-pseries.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:51 +1000
Subject: powerpc/rfi-flush: Always enable fallback flush on pseries
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-7-mpe@ellerman.id.au>

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

commit 84749a58b6e382f109abf1e734bc4dd43c2c25bb upstream.

This ensures the fallback flush area is always allocated on pseries,
so in case a LPAR is migrated from a patched to an unpatched system,
it is possible to enable the fallback flush in the target system.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |   10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -459,26 +459,18 @@ static void pseries_setup_rfi_flush(void
 
 	/* Enable by default */
 	enable = true;
+	types = L1D_FLUSH_FALLBACK;
 
 	rc = plpar_get_cpu_characteristics(&result);
 	if (rc == H_SUCCESS) {
-		types = L1D_FLUSH_NONE;
-
 		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;
 
-		/* Use fallback if nothing set in hcall */
-		if (types == L1D_FLUSH_NONE)
-			types = L1D_FLUSH_FALLBACK;
-
 		if ((!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) ||
 		    (!(result.behaviour & H_CPU_BEHAV_FAVOUR_SECURITY)))
 			enable = false;
-	} else {
-		/* Default to fallback if case hcall is not available */
-		types = L1D_FLUSH_FALLBACK;
 	}
 
 	setup_rfi_flush(types, enable);


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 07/23] powerpc/rfi-flush: Differentiate enabled and patched flush types

[Michael Ellerman]

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 0063d61ccfc011f379a31acaeba6de7c926fed2c upstream.

Currently the rfi-flush messages print 'Using <type> flush' for all
enabled_flush_types, but that is not necessarily true -- as now the
fallback flush is always enabled on pseries, but the fixup function
overwrites its nop/branch slot with other flush types, if available.

So, replace the 'Using <type> flush' messages with '<type> flush is
available'.

Also, print the patched flush types in the fixup function, so users
can know what is (not) being used (e.g., the slower, fallback flush,
or no flush type at all if flush is disabled via the debugfs switch).

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/setup_64.c    | 6 +++---
 arch/powerpc/lib/feature-fixups.c | 9 ++++++++-
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 568793009daa..eaa6039edddc 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -755,15 +755,15 @@ static void init_fallback_flush(void)
 void setup_rfi_flush(enum l1d_flush_type types, bool enable)
 {
 	if (types & L1D_FLUSH_FALLBACK) {
-		pr_info("rfi-flush: Using fallback displacement flush\n");
+		pr_info("rfi-flush: fallback displacement flush available\n");
 		init_fallback_flush();
 	}
 
 	if (types & L1D_FLUSH_ORI)
-		pr_info("rfi-flush: Using ori type flush\n");
+		pr_info("rfi-flush: ori type flush available\n");
 
 	if (types & L1D_FLUSH_MTTRIG)
-		pr_info("rfi-flush: Using mttrig type flush\n");
+		pr_info("rfi-flush: mttrig type flush available\n");
 
 	enabled_flush_types = types;
 
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index 46c8338a61bc..d89d54fa6acc 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -153,7 +153,14 @@ void do_rfi_flush_fixups(enum l1d_flush_type types)
 		patch_instruction(dest + 2, instrs[2]);
 	}
 
-	printk(KERN_DEBUG "rfi-flush: patched %d locations\n", i);
+	printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
+		(types == L1D_FLUSH_NONE)       ? "no" :
+		(types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
+		(types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
+							? "ori+mttrig type"
+							: "ori type" :
+		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
+						: "unknown");
 }
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
-- 
2.14.1

Patch "powerpc/rfi-flush: Differentiate enabled and patched flush types" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Differentiate enabled and patched flush types

to the 4.9-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-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:52 +1000
Subject: powerpc/rfi-flush: Differentiate enabled and patched flush types
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-8-mpe@ellerman.id.au>

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 0063d61ccfc011f379a31acaeba6de7c926fed2c upstream.

Currently the rfi-flush messages print 'Using <type> flush' for all
enabled_flush_types, but that is not necessarily true -- as now the
fallback flush is always enabled on pseries, but the fixup function
overwrites its nop/branch slot with other flush types, if available.

So, replace the 'Using <type> flush' messages with '<type> flush is
available'.

Also, print the patched flush types in the fixup function, so users
can know what is (not) being used (e.g., the slower, fallback flush,
or no flush type at all if flush is disabled via the debugfs switch).

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/setup_64.c    |    6 +++---
 arch/powerpc/lib/feature-fixups.c |    9 ++++++++-
 2 files changed, 11 insertions(+), 4 deletions(-)

--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -755,15 +755,15 @@ static void init_fallback_flush(void)
 void setup_rfi_flush(enum l1d_flush_type types, bool enable)
 {
 	if (types & L1D_FLUSH_FALLBACK) {
-		pr_info("rfi-flush: Using fallback displacement flush\n");
+		pr_info("rfi-flush: fallback displacement flush available\n");
 		init_fallback_flush();
 	}
 
 	if (types & L1D_FLUSH_ORI)
-		pr_info("rfi-flush: Using ori type flush\n");
+		pr_info("rfi-flush: ori type flush available\n");
 
 	if (types & L1D_FLUSH_MTTRIG)
-		pr_info("rfi-flush: Using mttrig type flush\n");
+		pr_info("rfi-flush: mttrig type flush available\n");
 
 	enabled_flush_types = types;
 
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -153,7 +153,14 @@ void do_rfi_flush_fixups(enum l1d_flush_
 		patch_instruction(dest + 2, instrs[2]);
 	}
 
-	printk(KERN_DEBUG "rfi-flush: patched %d locations\n", i);
+	printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
+		(types == L1D_FLUSH_NONE)       ? "no" :
+		(types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
+		(types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
+							? "ori+mttrig type"
+							: "ori type" :
+		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
+						: "unknown");
 }
 #endif /* CONFIG_PPC_BOOK3S_64 */
 


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 08/23] powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration

[Michael Ellerman]

commit 921bc6cf807ceb2ab8005319cf39f33494d6b100 upstream.

We might have migrated to a machine that uses a different flush type,
or doesn't need flushing at all.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/mobility.c | 3 +++
 arch/powerpc/platforms/pseries/pseries.h  | 2 ++
 arch/powerpc/platforms/pseries/setup.c    | 2 +-
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
index 6a5e7467445c..3784a7abfcc8 100644
--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -314,6 +314,9 @@ void post_mobility_fixup(void)
 		printk(KERN_ERR "Post-mobility device tree update "
 			"failed: %d\n", rc);
 
+	/* Possibly switch to a new RFI flush type */
+	pseries_setup_rfi_flush();
+
 	return;
 }
 
diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index b1be7b713fe6..62ff57cf6c24 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -79,4 +79,6 @@ extern struct pci_controller_ops pseries_pci_controller_ops;
 
 unsigned long pseries_memory_block_size(void);
 
+void pseries_setup_rfi_flush(void);
+
 #endif /* _PSERIES_PSERIES_H */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 626bf1ce1d80..483aa7a70d0a 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -450,7 +450,7 @@ static void __init find_and_init_phbs(void)
 	of_pci_check_probe_only();
 }
 
-static void pseries_setup_rfi_flush(void)
+void pseries_setup_rfi_flush(void)
 {
 	struct h_cpu_char_result result;
 	enum l1d_flush_type types;
-- 
2.14.1

Patch "powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration

to the 4.9-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-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:53 +1000
Subject: powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-9-mpe@ellerman.id.au>

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

commit 921bc6cf807ceb2ab8005319cf39f33494d6b100 upstream.

We might have migrated to a machine that uses a different flush type,
or doesn't need flushing at all.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/mobility.c |    3 +++
 arch/powerpc/platforms/pseries/pseries.h  |    2 ++
 arch/powerpc/platforms/pseries/setup.c    |    2 +-
 3 files changed, 6 insertions(+), 1 deletion(-)

--- a/arch/powerpc/platforms/pseries/mobility.c
+++ b/arch/powerpc/platforms/pseries/mobility.c
@@ -314,6 +314,9 @@ void post_mobility_fixup(void)
 		printk(KERN_ERR "Post-mobility device tree update "
 			"failed: %d\n", rc);
 
+	/* Possibly switch to a new RFI flush type */
+	pseries_setup_rfi_flush();
+
 	return;
 }
 
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -79,4 +79,6 @@ extern struct pci_controller_ops pseries
 
 unsigned long pseries_memory_block_size(void);
 
+void pseries_setup_rfi_flush(void);
+
 #endif /* _PSERIES_PSERIES_H */
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -450,7 +450,7 @@ static void __init find_and_init_phbs(vo
 	of_pci_check_probe_only();
 }
 
-static void pseries_setup_rfi_flush(void)
+void pseries_setup_rfi_flush(void)
 {
 	struct h_cpu_char_result result;
 	enum l1d_flush_type types;


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 09/23] powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags

[Michael Ellerman]

commit c4bc36628d7f8b664657d8bd6ad1c44c177880b7 upstream.

Add some additional values which have been defined for the
H_GET_CPU_CHARACTERISTICS hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/hvcall.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index dc0996b9d75d..9d978102bf0d 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -313,6 +313,9 @@
 #define H_CPU_CHAR_L1D_FLUSH_ORI30	(1ull << 61) // IBM bit 2
 #define H_CPU_CHAR_L1D_FLUSH_TRIG2	(1ull << 60) // IBM bit 3
 #define H_CPU_CHAR_L1D_THREAD_PRIV	(1ull << 59) // IBM bit 4
+#define H_CPU_CHAR_BRANCH_HINTS_HONORED	(1ull << 58) // IBM bit 5
+#define H_CPU_CHAR_THREAD_RECONFIG_CTRL	(1ull << 57) // IBM bit 6
+#define H_CPU_CHAR_COUNT_CACHE_DISABLED	(1ull << 56) // IBM bit 7
 
 #define H_CPU_BEHAV_FAVOUR_SECURITY	(1ull << 63) // IBM bit 0
 #define H_CPU_BEHAV_L1D_FLUSH_PR	(1ull << 62) // IBM bit 1
-- 
2.14.1

Patch "powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags

to the 4.9-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-add-new-h_get_cpu_characteristics-flags.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:54 +1000
Subject: powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-10-mpe@ellerman.id.au>

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

commit c4bc36628d7f8b664657d8bd6ad1c44c177880b7 upstream.

Add some additional values which have been defined for the
H_GET_CPU_CHARACTERISTICS hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/hvcall.h |    3 +++
 1 file changed, 3 insertions(+)

--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -313,6 +313,9 @@
 #define H_CPU_CHAR_L1D_FLUSH_ORI30	(1ull << 61) // IBM bit 2
 #define H_CPU_CHAR_L1D_FLUSH_TRIG2	(1ull << 60) // IBM bit 3
 #define H_CPU_CHAR_L1D_THREAD_PRIV	(1ull << 59) // IBM bit 4
+#define H_CPU_CHAR_BRANCH_HINTS_HONORED	(1ull << 58) // IBM bit 5
+#define H_CPU_CHAR_THREAD_RECONFIG_CTRL	(1ull << 57) // IBM bit 6
+#define H_CPU_CHAR_COUNT_CACHE_DISABLED	(1ull << 56) // IBM bit 7
 
 #define H_CPU_BEHAV_FAVOUR_SECURITY	(1ull << 63) // IBM bit 0
 #define H_CPU_BEHAV_L1D_FLUSH_PR	(1ull << 62) // IBM bit 1


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 10/23] powerpc: Add security feature flags for Spectre/Meltdown

[Michael Ellerman]

commit 9a868f634349e62922c226834aa23e3d1329ae7f upstream.

This commit adds security feature flags to reflect the settings we
receive from firmware regarding Spectre/Meltdown mitigations.

The feature names reflect the names we are given by firmware on bare
metal machines. See the hostboot source for details.

Arguably these could be firmware features, but that then requires them
to be read early in boot so they're available prior to asm feature
patching, but we don't actually want to use them for patching. We may
also want to dynamically update them in future, which would be
incompatible with the way firmware features work (at the moment at
least). So for now just make them separate flags.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/security_features.h | 65 ++++++++++++++++++++++++++++
 arch/powerpc/kernel/Makefile                 |  2 +-
 arch/powerpc/kernel/security.c               | 15 +++++++
 3 files changed, 81 insertions(+), 1 deletion(-)
 create mode 100644 arch/powerpc/include/asm/security_features.h
 create mode 100644 arch/powerpc/kernel/security.c

diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
new file mode 100644
index 000000000000..db00ad2c72c2
--- /dev/null
+++ b/arch/powerpc/include/asm/security_features.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Security related feature bit definitions.
+ *
+ * Copyright 2018, Michael Ellerman, IBM Corporation.
+ */
+
+#ifndef _ASM_POWERPC_SECURITY_FEATURES_H
+#define _ASM_POWERPC_SECURITY_FEATURES_H
+
+
+extern unsigned long powerpc_security_features;
+
+static inline void security_ftr_set(unsigned long feature)
+{
+	powerpc_security_features |= feature;
+}
+
+static inline void security_ftr_clear(unsigned long feature)
+{
+	powerpc_security_features &= ~feature;
+}
+
+static inline bool security_ftr_enabled(unsigned long feature)
+{
+	return !!(powerpc_security_features & feature);
+}
+
+
+// Features indicating support for Spectre/Meltdown mitigations
+
+// The L1-D cache can be flushed with ori r30,r30,0
+#define SEC_FTR_L1D_FLUSH_ORI30		0x0000000000000001ull
+
+// The L1-D cache can be flushed with mtspr 882,r0 (aka SPRN_TRIG2)
+#define SEC_FTR_L1D_FLUSH_TRIG2		0x0000000000000002ull
+
+// ori r31,r31,0 acts as a speculation barrier
+#define SEC_FTR_SPEC_BAR_ORI31		0x0000000000000004ull
+
+// Speculation past bctr is disabled
+#define SEC_FTR_BCCTRL_SERIALISED	0x0000000000000008ull
+
+// Entries in L1-D are private to a SMT thread
+#define SEC_FTR_L1D_THREAD_PRIV		0x0000000000000010ull
+
+// Indirect branch prediction cache disabled
+#define SEC_FTR_COUNT_CACHE_DISABLED	0x0000000000000020ull
+
+
+// Features indicating need for Spectre/Meltdown mitigations
+
+// The L1-D cache should be flushed on MSR[HV] 1->0 transition (hypervisor to guest)
+#define SEC_FTR_L1D_FLUSH_HV		0x0000000000000040ull
+
+// The L1-D cache should be flushed on MSR[PR] 0->1 transition (kernel to userspace)
+#define SEC_FTR_L1D_FLUSH_PR		0x0000000000000080ull
+
+// A speculation barrier should be used for bounds checks (Spectre variant 1)
+#define SEC_FTR_BNDS_CHK_SPEC_BAR	0x0000000000000100ull
+
+// Firmware configuration indicates user favours security over performance
+#define SEC_FTR_FAVOUR_SECURITY		0x0000000000000200ull
+
+#endif /* _ASM_POWERPC_SECURITY_FEATURES_H */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index adb52d101133..13885786282b 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -44,7 +44,7 @@ obj-$(CONFIG_PPC64)		+= setup_64.o sys_ppc32.o \
 obj-$(CONFIG_VDSO32)		+= vdso32/
 obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_ppc970.o cpu_setup_pa6t.o
-obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o
+obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o security.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= mce.o mce_power.o
 obj-$(CONFIG_PPC_BOOK3E_64)	+= exceptions-64e.o idle_book3e.o
 obj-$(CONFIG_PPC64)		+= vdso64/
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
new file mode 100644
index 000000000000..4ccba00d224c
--- /dev/null
+++ b/arch/powerpc/kernel/security.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Security related flags and so on.
+//
+// Copyright 2018, Michael Ellerman, IBM Corporation.
+
+#include <linux/kernel.h>
+#include <asm/security_features.h>
+
+
+unsigned long powerpc_security_features __read_mostly = \
+	SEC_FTR_L1D_FLUSH_HV | \
+	SEC_FTR_L1D_FLUSH_PR | \
+	SEC_FTR_BNDS_CHK_SPEC_BAR | \
+	SEC_FTR_FAVOUR_SECURITY;
-- 
2.14.1

Patch "powerpc: Add security feature flags for Spectre/Meltdown" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc: Add security feature flags for Spectre/Meltdown

to the 4.9-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-add-security-feature-flags-for-spectre-meltdown.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:55 +1000
Subject: powerpc: Add security feature flags for Spectre/Meltdown
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-11-mpe@ellerman.id.au>

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

commit 9a868f634349e62922c226834aa23e3d1329ae7f upstream.

This commit adds security feature flags to reflect the settings we
receive from firmware regarding Spectre/Meltdown mitigations.

The feature names reflect the names we are given by firmware on bare
metal machines. See the hostboot source for details.

Arguably these could be firmware features, but that then requires them
to be read early in boot so they're available prior to asm feature
patching, but we don't actually want to use them for patching. We may
also want to dynamically update them in future, which would be
incompatible with the way firmware features work (at the moment at
least). So for now just make them separate flags.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/security_features.h |   65 +++++++++++++++++++++++++++
 arch/powerpc/kernel/Makefile                 |    2 
 arch/powerpc/kernel/security.c               |   15 ++++++
 3 files changed, 81 insertions(+), 1 deletion(-)
 create mode 100644 arch/powerpc/include/asm/security_features.h
 create mode 100644 arch/powerpc/kernel/security.c

--- /dev/null
+++ b/arch/powerpc/include/asm/security_features.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Security related feature bit definitions.
+ *
+ * Copyright 2018, Michael Ellerman, IBM Corporation.
+ */
+
+#ifndef _ASM_POWERPC_SECURITY_FEATURES_H
+#define _ASM_POWERPC_SECURITY_FEATURES_H
+
+
+extern unsigned long powerpc_security_features;
+
+static inline void security_ftr_set(unsigned long feature)
+{
+	powerpc_security_features |= feature;
+}
+
+static inline void security_ftr_clear(unsigned long feature)
+{
+	powerpc_security_features &= ~feature;
+}
+
+static inline bool security_ftr_enabled(unsigned long feature)
+{
+	return !!(powerpc_security_features & feature);
+}
+
+
+// Features indicating support for Spectre/Meltdown mitigations
+
+// The L1-D cache can be flushed with ori r30,r30,0
+#define SEC_FTR_L1D_FLUSH_ORI30		0x0000000000000001ull
+
+// The L1-D cache can be flushed with mtspr 882,r0 (aka SPRN_TRIG2)
+#define SEC_FTR_L1D_FLUSH_TRIG2		0x0000000000000002ull
+
+// ori r31,r31,0 acts as a speculation barrier
+#define SEC_FTR_SPEC_BAR_ORI31		0x0000000000000004ull
+
+// Speculation past bctr is disabled
+#define SEC_FTR_BCCTRL_SERIALISED	0x0000000000000008ull
+
+// Entries in L1-D are private to a SMT thread
+#define SEC_FTR_L1D_THREAD_PRIV		0x0000000000000010ull
+
+// Indirect branch prediction cache disabled
+#define SEC_FTR_COUNT_CACHE_DISABLED	0x0000000000000020ull
+
+
+// Features indicating need for Spectre/Meltdown mitigations
+
+// The L1-D cache should be flushed on MSR[HV] 1->0 transition (hypervisor to guest)
+#define SEC_FTR_L1D_FLUSH_HV		0x0000000000000040ull
+
+// The L1-D cache should be flushed on MSR[PR] 0->1 transition (kernel to userspace)
+#define SEC_FTR_L1D_FLUSH_PR		0x0000000000000080ull
+
+// A speculation barrier should be used for bounds checks (Spectre variant 1)
+#define SEC_FTR_BNDS_CHK_SPEC_BAR	0x0000000000000100ull
+
+// Firmware configuration indicates user favours security over performance
+#define SEC_FTR_FAVOUR_SECURITY		0x0000000000000200ull
+
+#endif /* _ASM_POWERPC_SECURITY_FEATURES_H */
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -44,7 +44,7 @@ obj-$(CONFIG_PPC64)		+= setup_64.o sys_p
 obj-$(CONFIG_VDSO32)		+= vdso32/
 obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_ppc970.o cpu_setup_pa6t.o
-obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o
+obj-$(CONFIG_PPC_BOOK3S_64)	+= cpu_setup_power.o security.o
 obj-$(CONFIG_PPC_BOOK3S_64)	+= mce.o mce_power.o
 obj-$(CONFIG_PPC_BOOK3E_64)	+= exceptions-64e.o idle_book3e.o
 obj-$(CONFIG_PPC64)		+= vdso64/
--- /dev/null
+++ b/arch/powerpc/kernel/security.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Security related flags and so on.
+//
+// Copyright 2018, Michael Ellerman, IBM Corporation.
+
+#include <linux/kernel.h>
+#include <asm/security_features.h>
+
+
+unsigned long powerpc_security_features __read_mostly = \
+	SEC_FTR_L1D_FLUSH_HV | \
+	SEC_FTR_L1D_FLUSH_PR | \
+	SEC_FTR_BNDS_CHK_SPEC_BAR | \
+	SEC_FTR_FAVOUR_SECURITY;


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 11/23] powerpc/pseries: Set or clear security feature flags

[Michael Ellerman]

commit f636c14790ead6cc22cf62279b1f8d7e11a67116 upstream.

Now that we have feature flags for security related things, set or
clear them based on what we receive from the hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 43 ++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 483aa7a70d0a..a65515abe25f 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -66,6 +66,7 @@
 #include <asm/reg.h>
 #include <asm/plpar_wrappers.h>
 #include <asm/kexec.h>
+#include <asm/security_features.h>
 
 #include "pseries.h"
 
@@ -450,6 +451,40 @@ static void __init find_and_init_phbs(void)
 	of_pci_check_probe_only();
 }
 
+static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
+{
+	if (result->character & H_CPU_CHAR_SPEC_BAR_ORI31)
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (result->character & H_CPU_CHAR_BCCTRL_SERIALISED)
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (result->character & H_CPU_CHAR_L1D_FLUSH_ORI30)
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (result->character & H_CPU_CHAR_L1D_FLUSH_TRIG2)
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (result->character & H_CPU_CHAR_L1D_THREAD_PRIV)
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (result->character & H_CPU_CHAR_COUNT_CACHE_DISABLED)
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (!(result->character & H_CPU_BEHAV_FAVOUR_SECURITY))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (!(result->character & H_CPU_BEHAV_L1D_FLUSH_PR))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (!(result->character & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 void pseries_setup_rfi_flush(void)
 {
 	struct h_cpu_char_result result;
@@ -463,6 +498,8 @@ void pseries_setup_rfi_flush(void)
 
 	rc = plpar_get_cpu_characteristics(&result);
 	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)
@@ -473,6 +510,12 @@ void pseries_setup_rfi_flush(void)
 			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);
+
 	setup_rfi_flush(types, enable);
 }
 
-- 
2.14.1

Patch "powerpc/pseries: Set or clear security feature flags" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/pseries: Set or clear security feature flags

to the 4.9-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-set-or-clear-security-feature-flags.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:56 +1000
Subject: powerpc/pseries: Set or clear security feature flags
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-12-mpe@ellerman.id.au>

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

commit f636c14790ead6cc22cf62279b1f8d7e11a67116 upstream.

Now that we have feature flags for security related things, set or
clear them based on what we receive from the hypercall.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |   43 +++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -66,6 +66,7 @@
 #include <asm/reg.h>
 #include <asm/plpar_wrappers.h>
 #include <asm/kexec.h>
+#include <asm/security_features.h>
 
 #include "pseries.h"
 
@@ -450,6 +451,40 @@ static void __init find_and_init_phbs(vo
 	of_pci_check_probe_only();
 }
 
+static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
+{
+	if (result->character & H_CPU_CHAR_SPEC_BAR_ORI31)
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (result->character & H_CPU_CHAR_BCCTRL_SERIALISED)
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (result->character & H_CPU_CHAR_L1D_FLUSH_ORI30)
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (result->character & H_CPU_CHAR_L1D_FLUSH_TRIG2)
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (result->character & H_CPU_CHAR_L1D_THREAD_PRIV)
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (result->character & H_CPU_CHAR_COUNT_CACHE_DISABLED)
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (!(result->character & H_CPU_BEHAV_FAVOUR_SECURITY))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (!(result->character & H_CPU_BEHAV_L1D_FLUSH_PR))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (!(result->character & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 void pseries_setup_rfi_flush(void)
 {
 	struct h_cpu_char_result result;
@@ -463,6 +498,8 @@ void pseries_setup_rfi_flush(void)
 
 	rc = plpar_get_cpu_characteristics(&result);
 	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)
@@ -473,6 +510,12 @@ void pseries_setup_rfi_flush(void)
 			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);
+
 	setup_rfi_flush(types, enable);
 }
 


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 12/23] powerpc/powernv: Set or clear security feature flags

[Michael Ellerman]

commit 77addf6e95c8689e478d607176b399a6242a777e upstream.

Now that we have feature flags for security related things, set or
clear them based on what we see in the device tree provided by
firmware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 56 ++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 4764bc91570c..26fbaf14f87a 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -37,9 +37,63 @@
 #include <asm/smp.h>
 #include <asm/tm.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 
 #include "powernv.h"
 
+
+static bool fw_feature_is(const char *state, const char *name,
+			  struct device_node *fw_features)
+{
+	struct device_node *np;
+	bool rc = false;
+
+	np = of_get_child_by_name(fw_features, name);
+	if (np) {
+		rc = of_property_read_bool(np, state);
+		of_node_put(np);
+	}
+
+	return rc;
+}
+
+static void init_fw_feat_flags(struct device_node *np)
+{
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
+
+	if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
@@ -55,6 +109,8 @@ static void pnv_setup_rfi_flush(void)
 	of_node_put(np);
 
 	if (fw_features) {
+		init_fw_feat_flags(fw_features);
+
 		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
 		if (np && of_property_read_bool(np, "enabled"))
 			type = L1D_FLUSH_MTTRIG;
-- 
2.14.1

Patch "powerpc/powernv: Set or clear security feature flags" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/powernv: Set or clear security feature flags

to the 4.9-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-powernv-set-or-clear-security-feature-flags.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:57 +1000
Subject: powerpc/powernv: Set or clear security feature flags
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-13-mpe@ellerman.id.au>

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

commit 77addf6e95c8689e478d607176b399a6242a777e upstream.

Now that we have feature flags for security related things, set or
clear them based on what we see in the device tree provided by
firmware.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/powernv/setup.c |   56 +++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -37,9 +37,63 @@
 #include <asm/smp.h>
 #include <asm/tm.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 
 #include "powernv.h"
 
+
+static bool fw_feature_is(const char *state, const char *name,
+			  struct device_node *fw_features)
+{
+	struct device_node *np;
+	bool rc = false;
+
+	np = of_get_child_by_name(fw_features, name);
+	if (np) {
+		rc = of_property_read_bool(np, state);
+		of_node_put(np);
+	}
+
+	return rc;
+}
+
+static void init_fw_feat_flags(struct device_node *np)
+{
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
+		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
+
+	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
+
+	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
+		security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
+
+	if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
+		security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
+		security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
+
+	/*
+	 * The features below are enabled by default, so we instead look to see
+	 * if firmware has *disabled* them, and clear them if so.
+	 */
+	if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
+		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
+
+	if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
+		security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
+
+	if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
+		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
+}
+
 static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
@@ -55,6 +109,8 @@ static void pnv_setup_rfi_flush(void)
 	of_node_put(np);
 
 	if (fw_features) {
+		init_fw_feat_flags(fw_features);
+
 		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
 		if (np && of_property_read_bool(np, "enabled"))
 			type = L1D_FLUSH_MTTRIG;


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 13/23] powerpc/64s: Move cpu_show_meltdown()

[Michael Ellerman]

commit 8ad33041563a10b34988800c682ada14b2612533 upstream.

This landed in setup_64.c for no good reason other than we had nowhere
else to put it. Now that we have a security-related file, that is a
better place for it so move it.

[mpe: Add extern for rfi_flush to fix bisection break]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/security_features.h |  1 +
 arch/powerpc/kernel/security.c               | 11 +++++++++++
 arch/powerpc/kernel/setup_64.c               |  8 --------
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index db00ad2c72c2..400a9050e035 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -10,6 +10,7 @@
 
 
 extern unsigned long powerpc_security_features;
+extern bool rfi_flush;
 
 static inline void security_ftr_set(unsigned long feature)
 {
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 4ccba00d224c..564e7f182a16 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -5,6 +5,8 @@
 // Copyright 2018, Michael Ellerman, IBM Corporation.
 
 #include <linux/kernel.h>
+#include <linux/device.h>
+
 #include <asm/security_features.h>
 
 
@@ -13,3 +15,12 @@ unsigned long powerpc_security_features __read_mostly = \
 	SEC_FTR_L1D_FLUSH_PR | \
 	SEC_FTR_BNDS_CHK_SPEC_BAR | \
 	SEC_FTR_FAVOUR_SECURITY;
+
+
+ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (rfi_flush)
+		return sprintf(buf, "Mitigation: RFI Flush\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index eaa6039edddc..eda7eefe4927 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -805,12 +805,4 @@ static __init int rfi_flush_debugfs_init(void)
 }
 device_initcall(rfi_flush_debugfs_init);
 #endif
-
-ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
-{
-	if (rfi_flush)
-		return sprintf(buf, "Mitigation: RFI Flush\n");
-
-	return sprintf(buf, "Vulnerable\n");
-}
 #endif /* CONFIG_PPC_BOOK3S_64 */
-- 
2.14.1

Patch "powerpc/64s: Move cpu_show_meltdown()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Move cpu_show_meltdown()

to the 4.9-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-64s-move-cpu_show_meltdown.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:58 +1000
Subject: powerpc/64s: Move cpu_show_meltdown()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-14-mpe@ellerman.id.au>

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

commit 8ad33041563a10b34988800c682ada14b2612533 upstream.

This landed in setup_64.c for no good reason other than we had nowhere
else to put it. Now that we have a security-related file, that is a
better place for it so move it.

[mpe: Add extern for rfi_flush to fix bisection break]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/security_features.h |    1 +
 arch/powerpc/kernel/security.c               |   11 +++++++++++
 arch/powerpc/kernel/setup_64.c               |    8 --------
 3 files changed, 12 insertions(+), 8 deletions(-)

--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -10,6 +10,7 @@
 
 
 extern unsigned long powerpc_security_features;
+extern bool rfi_flush;
 
 static inline void security_ftr_set(unsigned long feature)
 {
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -5,6 +5,8 @@
 // Copyright 2018, Michael Ellerman, IBM Corporation.
 
 #include <linux/kernel.h>
+#include <linux/device.h>
+
 #include <asm/security_features.h>
 
 
@@ -13,3 +15,12 @@ unsigned long powerpc_security_features
 	SEC_FTR_L1D_FLUSH_PR | \
 	SEC_FTR_BNDS_CHK_SPEC_BAR | \
 	SEC_FTR_FAVOUR_SECURITY;
+
+
+ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (rfi_flush)
+		return sprintf(buf, "Mitigation: RFI Flush\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -805,12 +805,4 @@ static __init int rfi_flush_debugfs_init
 }
 device_initcall(rfi_flush_debugfs_init);
 #endif
-
-ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
-{
-	if (rfi_flush)
-		return sprintf(buf, "Mitigation: RFI Flush\n");
-
-	return sprintf(buf, "Vulnerable\n");
-}
 #endif /* CONFIG_PPC_BOOK3S_64 */


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 14/23] powerpc/64s: Enhance the information in cpu_show_meltdown()

[Michael Ellerman]

commit ff348355e9c72493947be337bb4fae4fc1a41eba upstream.

Now that we have the security feature flags we can make the
information displayed in the "meltdown" file more informative.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/security.c | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 564e7f182a16..865db6f8bcca 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -6,6 +6,7 @@
 
 #include <linux/kernel.h>
 #include <linux/device.h>
+#include <linux/seq_buf.h>
 
 #include <asm/security_features.h>
 
@@ -19,8 +20,33 @@ unsigned long powerpc_security_features __read_mostly = \
 
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	if (rfi_flush)
-		return sprintf(buf, "Mitigation: RFI Flush\n");
+	bool thread_priv;
+
+	thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (rfi_flush || thread_priv) {
+		struct seq_buf s;
+		seq_buf_init(&s, buf, PAGE_SIZE - 1);
+
+		seq_buf_printf(&s, "Mitigation: ");
+
+		if (rfi_flush)
+			seq_buf_printf(&s, "RFI Flush");
+
+		if (rfi_flush && thread_priv)
+			seq_buf_printf(&s, ", ");
+
+		if (thread_priv)
+			seq_buf_printf(&s, "L1D private per thread");
+
+		seq_buf_printf(&s, "\n");
+
+		return s.len;
+	}
+
+	if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
+	    !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
+		return sprintf(buf, "Not affected\n");
 
 	return sprintf(buf, "Vulnerable\n");
 }
-- 
2.14.1

Patch "powerpc/64s: Enhance the information in cpu_show_meltdown()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Enhance the information in cpu_show_meltdown()

to the 4.9-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-64s-enhance-the-information-in-cpu_show_meltdown.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:08:59 +1000
Subject: powerpc/64s: Enhance the information in cpu_show_meltdown()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-15-mpe@ellerman.id.au>

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

commit ff348355e9c72493947be337bb4fae4fc1a41eba upstream.

Now that we have the security feature flags we can make the
information displayed in the "meltdown" file more informative.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/security.c |   30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -6,6 +6,7 @@
 
 #include <linux/kernel.h>
 #include <linux/device.h>
+#include <linux/seq_buf.h>
 
 #include <asm/security_features.h>
 
@@ -19,8 +20,33 @@ unsigned long powerpc_security_features
 
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	if (rfi_flush)
-		return sprintf(buf, "Mitigation: RFI Flush\n");
+	bool thread_priv;
+
+	thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV);
+
+	if (rfi_flush || thread_priv) {
+		struct seq_buf s;
+		seq_buf_init(&s, buf, PAGE_SIZE - 1);
+
+		seq_buf_printf(&s, "Mitigation: ");
+
+		if (rfi_flush)
+			seq_buf_printf(&s, "RFI Flush");
+
+		if (rfi_flush && thread_priv)
+			seq_buf_printf(&s, ", ");
+
+		if (thread_priv)
+			seq_buf_printf(&s, "L1D private per thread");
+
+		seq_buf_printf(&s, "\n");
+
+		return s.len;
+	}
+
+	if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
+	    !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
+		return sprintf(buf, "Not affected\n");
 
 	return sprintf(buf, "Vulnerable\n");
 }


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 15/23] powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()

[Michael Ellerman]

commit 37c0bdd00d3ae83369ab60a6712c28e11e6458d5 upstream.

Now that we have the security flags we can significantly simplify the
code in pnv_setup_rfi_flush(), because we can use the flags instead of
checking device tree properties and because the security flags have
pessimistic defaults.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/powernv/setup.c | 41 +++++++++-------------------------
 1 file changed, 10 insertions(+), 31 deletions(-)

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 26fbaf14f87a..2c646f5bd144 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -65,7 +65,7 @@ static void init_fw_feat_flags(struct device_node *np)
 	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
 		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
 
-	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+	if (fw_feature_is("enabled", "inst-l1d-flush-ori30,30,0", np))
 		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
 
 	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
@@ -98,11 +98,10 @@ static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
 	enum l1d_flush_type type;
-	int enable;
+	bool enable;
 
 	/* Default to fallback in case fw-features are not available */
 	type = L1D_FLUSH_FALLBACK;
-	enable = 1;
 
 	np = of_find_node_by_name(NULL, "ibm,opal");
 	fw_features = of_get_child_by_name(np, "fw-features");
@@ -110,40 +109,20 @@ static void pnv_setup_rfi_flush(void)
 
 	if (fw_features) {
 		init_fw_feat_flags(fw_features);
+		of_node_put(fw_features);
 
-		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
-		if (np && of_property_read_bool(np, "enabled"))
+		if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2))
 			type = L1D_FLUSH_MTTRIG;
 
-		of_node_put(np);
-
-		np = of_get_child_by_name(fw_features, "inst-l1d-flush-ori30,30,0");
-		if (np && of_property_read_bool(np, "enabled"))
+		if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30))
 			type = L1D_FLUSH_ORI;
-
-		of_node_put(np);
-
-		/* Enable unless firmware says NOT to */
-		enable = 2;
-		np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-hv-1-to-0");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable--;
-
-		of_node_put(np);
-
-		np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-pr-0-to-1");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable--;
-
-		np = of_get_child_by_name(fw_features, "speculation-policy-favor-security");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable = 0;
-
-		of_node_put(np);
-		of_node_put(fw_features);
 	}
 
-	setup_rfi_flush(type, enable > 0);
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
+		 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)   || \
+		  security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
+
+	setup_rfi_flush(type, enable);
 }
 
 static void __init pnv_setup_arch(void)
-- 
2.14.1

Patch "powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()

to the 4.9-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-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:00 +1000
Subject: powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-16-mpe@ellerman.id.au>

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

commit 37c0bdd00d3ae83369ab60a6712c28e11e6458d5 upstream.

Now that we have the security flags we can significantly simplify the
code in pnv_setup_rfi_flush(), because we can use the flags instead of
checking device tree properties and because the security flags have
pessimistic defaults.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/powernv/setup.c |   41 ++++++++-------------------------
 1 file changed, 10 insertions(+), 31 deletions(-)

--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -65,7 +65,7 @@ static void init_fw_feat_flags(struct de
 	if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
 		security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
 
-	if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
+	if (fw_feature_is("enabled", "inst-l1d-flush-ori30,30,0", np))
 		security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
 
 	if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
@@ -98,11 +98,10 @@ static void pnv_setup_rfi_flush(void)
 {
 	struct device_node *np, *fw_features;
 	enum l1d_flush_type type;
-	int enable;
+	bool enable;
 
 	/* Default to fallback in case fw-features are not available */
 	type = L1D_FLUSH_FALLBACK;
-	enable = 1;
 
 	np = of_find_node_by_name(NULL, "ibm,opal");
 	fw_features = of_get_child_by_name(np, "fw-features");
@@ -110,40 +109,20 @@ static void pnv_setup_rfi_flush(void)
 
 	if (fw_features) {
 		init_fw_feat_flags(fw_features);
+		of_node_put(fw_features);
 
-		np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
-		if (np && of_property_read_bool(np, "enabled"))
+		if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2))
 			type = L1D_FLUSH_MTTRIG;
 
-		of_node_put(np);
-
-		np = of_get_child_by_name(fw_features, "inst-l1d-flush-ori30,30,0");
-		if (np && of_property_read_bool(np, "enabled"))
+		if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30))
 			type = L1D_FLUSH_ORI;
-
-		of_node_put(np);
-
-		/* Enable unless firmware says NOT to */
-		enable = 2;
-		np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-hv-1-to-0");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable--;
-
-		of_node_put(np);
-
-		np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-pr-0-to-1");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable--;
-
-		np = of_get_child_by_name(fw_features, "speculation-policy-favor-security");
-		if (np && of_property_read_bool(np, "disabled"))
-			enable = 0;
-
-		of_node_put(np);
-		of_node_put(fw_features);
 	}
 
-	setup_rfi_flush(type, enable > 0);
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
+		 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR)   || \
+		  security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
+
+	setup_rfi_flush(type, enable);
 }
 
 static void __init pnv_setup_arch(void)


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 16/23] powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()

[Michael Ellerman]

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@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 27 ++++++++++++---------------
 1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index a65515abe25f..28d7cd2001cc 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -492,30 +492,27 @@ 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);
 }
 
-- 
2.14.1

Patch "powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()" has been added to the 4.9-stable tree

[gregkh]

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 4.9-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-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:01 +1000
Subject: powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-17-mpe@ellerman.id.au>

From: Michael Ellerman <mpe@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@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@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
@@ -492,30 +492,27 @@ 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@ellerman.id.au are

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 17/23] powerpc/64s: Wire up cpu_show_spectre_v1()

[Michael Ellerman]

commit 56986016cb8cd9050e601831fe89f332b4e3c46e upstream.

Add a definition for cpu_show_spectre_v1() to override the generic
version. Currently this just prints "Not affected" or "Vulnerable"
based on the firmware flag.

Although the kernel does have array_index_nospec() in a few places, we
haven't yet audited all the powerpc code to see where it's necessary,
so for now we don't list that as a mitigation.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/security.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 865db6f8bcca..0eace3cac818 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -50,3 +50,11 @@ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, cha
 
 	return sprintf(buf, "Vulnerable\n");
 }
+
+ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR))
+		return sprintf(buf, "Not affected\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}
-- 
2.14.1

Patch "powerpc/64s: Wire up cpu_show_spectre_v1()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Wire up cpu_show_spectre_v1()

to the 4.9-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-64s-wire-up-cpu_show_spectre_v1.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:02 +1000
Subject: powerpc/64s: Wire up cpu_show_spectre_v1()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-18-mpe@ellerman.id.au>

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

commit 56986016cb8cd9050e601831fe89f332b4e3c46e upstream.

Add a definition for cpu_show_spectre_v1() to override the generic
version. Currently this just prints "Not affected" or "Vulnerable"
based on the firmware flag.

Although the kernel does have array_index_nospec() in a few places, we
haven't yet audited all the powerpc code to see where it's necessary,
so for now we don't list that as a mitigation.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/security.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -50,3 +50,11 @@ ssize_t cpu_show_meltdown(struct device
 
 	return sprintf(buf, "Vulnerable\n");
 }
+
+ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR))
+		return sprintf(buf, "Not affected\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 18/23] powerpc/64s: Wire up cpu_show_spectre_v2()

[Michael Ellerman]

commit d6fbe1c55c55c6937cbea3531af7da84ab7473c3 upstream.

Add a definition for cpu_show_spectre_v2() to override the generic
version. This has several permuations, though in practice some may not
occur we cater for any combination.

The most verbose is:

  Mitigation: Indirect branch serialisation (kernel only), Indirect
  branch cache disabled, ori31 speculation barrier enabled

We don't treat the ori31 speculation barrier as a mitigation on its
own, because it has to be *used* by code in order to be a mitigation
and we don't know if userspace is doing that. So if that's all we see
we say:

  Vulnerable, ori31 speculation barrier enabled

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/security.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 0eace3cac818..2cee3dcd231b 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -58,3 +58,36 @@ ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, c
 
 	return sprintf(buf, "Vulnerable\n");
 }
+
+ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	bool bcs, ccd, ori;
+	struct seq_buf s;
+
+	seq_buf_init(&s, buf, PAGE_SIZE - 1);
+
+	bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED);
+	ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED);
+	ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (bcs || ccd) {
+		seq_buf_printf(&s, "Mitigation: ");
+
+		if (bcs)
+			seq_buf_printf(&s, "Indirect branch serialisation (kernel only)");
+
+		if (bcs && ccd)
+			seq_buf_printf(&s, ", ");
+
+		if (ccd)
+			seq_buf_printf(&s, "Indirect branch cache disabled");
+	} else
+		seq_buf_printf(&s, "Vulnerable");
+
+	if (ori)
+		seq_buf_printf(&s, ", ori31 speculation barrier enabled");
+
+	seq_buf_printf(&s, "\n");
+
+	return s.len;
+}
-- 
2.14.1

Patch "powerpc/64s: Wire up cpu_show_spectre_v2()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Wire up cpu_show_spectre_v2()

to the 4.9-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-64s-wire-up-cpu_show_spectre_v2.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:03 +1000
Subject: powerpc/64s: Wire up cpu_show_spectre_v2()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-19-mpe@ellerman.id.au>

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

commit d6fbe1c55c55c6937cbea3531af7da84ab7473c3 upstream.

Add a definition for cpu_show_spectre_v2() to override the generic
version. This has several permuations, though in practice some may not
occur we cater for any combination.

The most verbose is:

  Mitigation: Indirect branch serialisation (kernel only), Indirect
  branch cache disabled, ori31 speculation barrier enabled

We don't treat the ori31 speculation barrier as a mitigation on its
own, because it has to be *used* by code in order to be a mitigation
and we don't know if userspace is doing that. So if that's all we see
we say:

  Vulnerable, ori31 speculation barrier enabled

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/security.c |   33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -58,3 +58,36 @@ ssize_t cpu_show_spectre_v1(struct devic
 
 	return sprintf(buf, "Vulnerable\n");
 }
+
+ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	bool bcs, ccd, ori;
+	struct seq_buf s;
+
+	seq_buf_init(&s, buf, PAGE_SIZE - 1);
+
+	bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED);
+	ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED);
+	ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31);
+
+	if (bcs || ccd) {
+		seq_buf_printf(&s, "Mitigation: ");
+
+		if (bcs)
+			seq_buf_printf(&s, "Indirect branch serialisation (kernel only)");
+
+		if (bcs && ccd)
+			seq_buf_printf(&s, ", ");
+
+		if (ccd)
+			seq_buf_printf(&s, "Indirect branch cache disabled");
+	} else
+		seq_buf_printf(&s, "Vulnerable");
+
+	if (ori)
+		seq_buf_printf(&s, ", ori31 speculation barrier enabled");
+
+	seq_buf_printf(&s, "\n");
+
+	return s.len;
+}


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 19/23] powerpc/pseries: Fix clearing of security feature flags

[Michael Ellerman]

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 0f9bdfe3c77091e8704d2e510eb7c2c2c6cde524 upstream.

The H_CPU_BEHAV_* flags should be checked for in the 'behaviour' field
of 'struct h_cpu_char_result' -- 'character' is for H_CPU_CHAR_*
flags.

Found by playing around with QEMU's implementation of the hypercall:

  H_CPU_CHAR=0xf000000000000000
  H_CPU_BEHAV=0x0000000000000000

  This clears H_CPU_BEHAV_FAVOUR_SECURITY and H_CPU_BEHAV_L1D_FLUSH_PR
  so pseries_setup_rfi_flush() disables 'rfi_flush'; and it also
  clears H_CPU_CHAR_L1D_THREAD_PRIV flag. So there is no RFI flush
  mitigation at all for cpu_show_meltdown() to report; but currently
  it does:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Mitigation: RFI Flush

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Not affected

  H_CPU_CHAR=0x0000000000000000
  H_CPU_BEHAV=0xf000000000000000

  This sets H_CPU_BEHAV_BNDS_CHK_SPEC_BAR so cpu_show_spectre_v1() should
  report vulnerable; but currently it doesn't:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Not affected

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Vulnerable

Brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 28d7cd2001cc..8d9f591e7950 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -475,13 +475,13 @@ static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
 	 * The features below are enabled by default, so we instead look to see
 	 * if firmware has *disabled* them, and clear them if so.
 	 */
-	if (!(result->character & H_CPU_BEHAV_FAVOUR_SECURITY))
+	if (!(result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY))
 		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
 
-	if (!(result->character & H_CPU_BEHAV_L1D_FLUSH_PR))
+	if (!(result->behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))
 		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
 
-	if (!(result->character & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
+	if (!(result->behaviour & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
 		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
 }
 
-- 
2.14.1

Patch "powerpc/pseries: Fix clearing of security feature flags" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/pseries: Fix clearing of security feature flags

to the 4.9-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-fix-clearing-of-security-feature-flags.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:04 +1000
Subject: powerpc/pseries: Fix clearing of security feature flags
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-20-mpe@ellerman.id.au>

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 0f9bdfe3c77091e8704d2e510eb7c2c2c6cde524 upstream.

The H_CPU_BEHAV_* flags should be checked for in the 'behaviour' field
of 'struct h_cpu_char_result' -- 'character' is for H_CPU_CHAR_*
flags.

Found by playing around with QEMU's implementation of the hypercall:

  H_CPU_CHAR=0xf000000000000000
  H_CPU_BEHAV=0x0000000000000000

  This clears H_CPU_BEHAV_FAVOUR_SECURITY and H_CPU_BEHAV_L1D_FLUSH_PR
  so pseries_setup_rfi_flush() disables 'rfi_flush'; and it also
  clears H_CPU_CHAR_L1D_THREAD_PRIV flag. So there is no RFI flush
  mitigation at all for cpu_show_meltdown() to report; but currently
  it does:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Mitigation: RFI Flush

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Not affected

  H_CPU_CHAR=0x0000000000000000
  H_CPU_BEHAV=0xf000000000000000

  This sets H_CPU_BEHAV_BNDS_CHK_SPEC_BAR so cpu_show_spectre_v1() should
  report vulnerable; but currently it doesn't:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Not affected

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Vulnerable

Brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -475,13 +475,13 @@ static void init_cpu_char_feature_flags(
 	 * The features below are enabled by default, so we instead look to see
 	 * if firmware has *disabled* them, and clear them if so.
 	 */
-	if (!(result->character & H_CPU_BEHAV_FAVOUR_SECURITY))
+	if (!(result->behaviour & H_CPU_BEHAV_FAVOUR_SECURITY))
 		security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
 
-	if (!(result->character & H_CPU_BEHAV_L1D_FLUSH_PR))
+	if (!(result->behaviour & H_CPU_BEHAV_L1D_FLUSH_PR))
 		security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
 
-	if (!(result->character & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
+	if (!(result->behaviour & H_CPU_BEHAV_BNDS_CHK_SPEC_BAR))
 		security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
 }
 


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 20/23] powerpc: Move default security feature flags

[Michael Ellerman]

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit e7347a86830f38dc3e40c8f7e28c04412b12a2e7 upstream.

This moves the definition of the default security feature flags
(i.e., enabled by default) closer to the security feature flags.

This can be used to restore current flags to the default flags.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/include/asm/security_features.h | 8 ++++++++
 arch/powerpc/kernel/security.c               | 7 +------
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index 400a9050e035..fa4d2e1cf772 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -63,4 +63,12 @@ static inline bool security_ftr_enabled(unsigned long feature)
 // Firmware configuration indicates user favours security over performance
 #define SEC_FTR_FAVOUR_SECURITY		0x0000000000000200ull
 
+
+// Features enabled by default
+#define SEC_FTR_DEFAULT \
+	(SEC_FTR_L1D_FLUSH_HV | \
+	 SEC_FTR_L1D_FLUSH_PR | \
+	 SEC_FTR_BNDS_CHK_SPEC_BAR | \
+	 SEC_FTR_FAVOUR_SECURITY)
+
 #endif /* _ASM_POWERPC_SECURITY_FEATURES_H */
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 2cee3dcd231b..bab5a27ea805 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -11,12 +11,7 @@
 #include <asm/security_features.h>
 
 
-unsigned long powerpc_security_features __read_mostly = \
-	SEC_FTR_L1D_FLUSH_HV | \
-	SEC_FTR_L1D_FLUSH_PR | \
-	SEC_FTR_BNDS_CHK_SPEC_BAR | \
-	SEC_FTR_FAVOUR_SECURITY;
-
+unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT;
 
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
 {
-- 
2.14.1

Patch "powerpc: Move default security feature flags" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc: Move default security feature flags

to the 4.9-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-move-default-security-feature-flags.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:05 +1000
Subject: powerpc: Move default security feature flags
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-21-mpe@ellerman.id.au>

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit e7347a86830f38dc3e40c8f7e28c04412b12a2e7 upstream.

This moves the definition of the default security feature flags
(i.e., enabled by default) closer to the security feature flags.

This can be used to restore current flags to the default flags.

Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/security_features.h |    8 ++++++++
 arch/powerpc/kernel/security.c               |    7 +------
 2 files changed, 9 insertions(+), 6 deletions(-)

--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -63,4 +63,12 @@ static inline bool security_ftr_enabled(
 // Firmware configuration indicates user favours security over performance
 #define SEC_FTR_FAVOUR_SECURITY		0x0000000000000200ull
 
+
+// Features enabled by default
+#define SEC_FTR_DEFAULT \
+	(SEC_FTR_L1D_FLUSH_HV | \
+	 SEC_FTR_L1D_FLUSH_PR | \
+	 SEC_FTR_BNDS_CHK_SPEC_BAR | \
+	 SEC_FTR_FAVOUR_SECURITY)
+
 #endif /* _ASM_POWERPC_SECURITY_FEATURES_H */
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -11,12 +11,7 @@
 #include <asm/security_features.h>
 
 
-unsigned long powerpc_security_features __read_mostly = \
-	SEC_FTR_L1D_FLUSH_HV | \
-	SEC_FTR_L1D_FLUSH_PR | \
-	SEC_FTR_BNDS_CHK_SPEC_BAR | \
-	SEC_FTR_FAVOUR_SECURITY;
-
+unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT;
 
 ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
 {


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 21/23] powerpc/pseries: Restore default security feature flags on setup

[Michael Ellerman]

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 6232774f1599028a15418179d17f7df47ede770a upstream.

After migration the security feature flags might have changed (e.g.,
destination system with unpatched firmware), but some flags are not
set/clear again in init_cpu_char_feature_flags() because it assumes
the security flags to be the defaults.

Additionally, if the H_GET_CPU_CHARACTERISTICS hypercall fails then
init_cpu_char_feature_flags() does not run again, which potentially
might leave the system in an insecure or sub-optimal configuration.

So, just restore the security feature flags to the defaults assumed
by init_cpu_char_feature_flags() so it can set/clear them correctly,
and to ensure safe settings are in place in case the hypercall fail.

Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Depends-on: 19887d6a28e2 ("powerpc: Move default security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/platforms/pseries/setup.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 8d9f591e7950..7349c05032be 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -453,6 +453,10 @@ static void __init find_and_init_phbs(void)
 
 static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
 {
+	/*
+	 * The features below are disabled by default, so we instead look to see
+	 * if firmware has *enabled* them, and set them if so.
+	 */
 	if (result->character & H_CPU_CHAR_SPEC_BAR_ORI31)
 		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
 
@@ -492,6 +496,13 @@ void pseries_setup_rfi_flush(void)
 	bool enable;
 	long rc;
 
+	/*
+	 * Set features to the defaults assumed by init_cpu_char_feature_flags()
+	 * so it can set/clear again any features that might have changed after
+	 * migration, and in case the hypercall fails and it is not even called.
+	 */
+	powerpc_security_features = SEC_FTR_DEFAULT;
+
 	rc = plpar_get_cpu_characteristics(&result);
 	if (rc == H_SUCCESS)
 		init_cpu_char_feature_flags(&result);
-- 
2.14.1

Patch "powerpc/pseries: Restore default security feature flags on setup" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/pseries: Restore default security feature flags on setup

to the 4.9-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-restore-default-security-feature-flags-on-setup.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:06 +1000
Subject: powerpc/pseries: Restore default security feature flags on setup
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-22-mpe@ellerman.id.au>

From: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>

commit 6232774f1599028a15418179d17f7df47ede770a upstream.

After migration the security feature flags might have changed (e.g.,
destination system with unpatched firmware), but some flags are not
set/clear again in init_cpu_char_feature_flags() because it assumes
the security flags to be the defaults.

Additionally, if the H_GET_CPU_CHARACTERISTICS hypercall fails then
init_cpu_char_feature_flags() does not run again, which potentially
might leave the system in an insecure or sub-optimal configuration.

So, just restore the security feature flags to the defaults assumed
by init_cpu_char_feature_flags() so it can set/clear them correctly,
and to ensure safe settings are in place in case the hypercall fail.

Fixes: f636c14790ea ("powerpc/pseries: Set or clear security feature flags")
Depends-on: 19887d6a28e2 ("powerpc: Move default security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/platforms/pseries/setup.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -453,6 +453,10 @@ static void __init find_and_init_phbs(vo
 
 static void init_cpu_char_feature_flags(struct h_cpu_char_result *result)
 {
+	/*
+	 * The features below are disabled by default, so we instead look to see
+	 * if firmware has *enabled* them, and set them if so.
+	 */
 	if (result->character & H_CPU_CHAR_SPEC_BAR_ORI31)
 		security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
 
@@ -492,6 +496,13 @@ void pseries_setup_rfi_flush(void)
 	bool enable;
 	long rc;
 
+	/*
+	 * Set features to the defaults assumed by init_cpu_char_feature_flags()
+	 * so it can set/clear again any features that might have changed after
+	 * migration, and in case the hypercall fails and it is not even called.
+	 */
+	powerpc_security_features = SEC_FTR_DEFAULT;
+
 	rc = plpar_get_cpu_characteristics(&result);
 	if (rc == H_SUCCESS)
 		init_cpu_char_feature_flags(&result);


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 22/23] powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()

[Michael Ellerman]

commit 501a78cbc17c329fabf8e9750a1e9ab810c88a0e upstream.

The recent LPM changes to setup_rfi_flush() are causing some section
mismatch warnings because we removed the __init annotation on
setup_rfi_flush():

  The function setup_rfi_flush() references
  the function __init ppc64_bolted_size().
  the function __init memblock_alloc_base().

The references are actually in init_fallback_flush(), but that is
inlined into setup_rfi_flush().

These references are safe because:
 - only pseries calls setup_rfi_flush() at runtime
 - pseries always passes L1D_FLUSH_FALLBACK at boot
 - so the fallback flush area will always be allocated
 - so the check in init_fallback_flush() will always return early:
   /* Only allocate the fallback flush area once (at boot time). */
   if (l1d_flush_fallback_area)
   	return;

 - and therefore we won't actually call the freed init routines.

We should rework the code to make it safer by default rather than
relying on the above, but for now as a quick-fix just add a __ref
annotation to squash the warning.

Fixes: abf110f3e1ce ("powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 arch/powerpc/kernel/setup_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index eda7eefe4927..fdba10695208 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -726,7 +726,7 @@ void rfi_flush_enable(bool enable)
 	rfi_flush = enable;
 }
 
-static void init_fallback_flush(void)
+static void __ref init_fallback_flush(void)
 {
 	u64 l1d_size, limit;
 	int cpu;
-- 
2.14.1

Patch "powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()

to the 4.9-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-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:07 +1000
Subject: powerpc/64s: Fix section mismatch warnings from setup_rfi_flush()
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-23-mpe@ellerman.id.au>

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

commit 501a78cbc17c329fabf8e9750a1e9ab810c88a0e upstream.

The recent LPM changes to setup_rfi_flush() are causing some section
mismatch warnings because we removed the __init annotation on
setup_rfi_flush():

  The function setup_rfi_flush() references
  the function __init ppc64_bolted_size().
  the function __init memblock_alloc_base().

The references are actually in init_fallback_flush(), but that is
inlined into setup_rfi_flush().

These references are safe because:
 - only pseries calls setup_rfi_flush() at runtime
 - pseries always passes L1D_FLUSH_FALLBACK at boot
 - so the fallback flush area will always be allocated
 - so the check in init_fallback_flush() will always return early:
   /* Only allocate the fallback flush area once (at boot time). */
   if (l1d_flush_fallback_area)
   	return;

 - and therefore we won't actually call the freed init routines.

We should rework the code to make it safer by default rather than
relying on the above, but for now as a quick-fix just add a __ref
annotation to squash the warning.

Fixes: abf110f3e1ce ("powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/kernel/setup_64.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -726,7 +726,7 @@ void rfi_flush_enable(bool enable)
 	rfi_flush = enable;
 }
 
-static void init_fallback_flush(void)
+static void __ref init_fallback_flush(void)
 {
 	u64 l1d_size, limit;
 	int cpu;


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

[PATCH stable 4.9 23/23] powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit

[Michael Ellerman]

From: Nicholas Piggin <npiggin@gmail.com>

commit a048a07d7f4535baa4cbad6bc024f175317ab938 upstream.

On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.

This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.

Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.

Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.

Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.

Thanks to Michal Suchánek for bug fixes and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/powerpc/include/asm/exception-64s.h     |  29 ++++++
 arch/powerpc/include/asm/feature-fixups.h    |  19 ++++
 arch/powerpc/include/asm/security_features.h |  11 ++
 arch/powerpc/kernel/exceptions-64s.S         |  16 ++-
 arch/powerpc/kernel/security.c               | 149 +++++++++++++++++++++++++++
 arch/powerpc/kernel/vmlinux.lds.S            |  14 +++
 arch/powerpc/lib/feature-fixups.c            | 115 +++++++++++++++++++++
 arch/powerpc/platforms/powernv/setup.c       |   1 +
 arch/powerpc/platforms/pseries/setup.c       |   1 +
 9 files changed, 354 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h
index 903e76a9f158..e2200100828d 100644
--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -51,6 +51,27 @@
 #define EX_PPR		88	/* SMT thread status register (priority) */
 #define EX_CTR		96
 
+#define STF_ENTRY_BARRIER_SLOT						\
+	STF_ENTRY_BARRIER_FIXUP_SECTION;				\
+	nop;								\
+	nop;								\
+	nop
+
+#define STF_EXIT_BARRIER_SLOT						\
+	STF_EXIT_BARRIER_FIXUP_SECTION;					\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop
+
+/*
+ * r10 must be free to use, r13 must be paca
+ */
+#define INTERRUPT_TO_KERNEL						\
+	STF_ENTRY_BARRIER_SLOT
+
 /*
  * Macros for annotating the expected destination of (h)rfid
  *
@@ -67,16 +88,19 @@
 	rfid
 
 #define RFI_TO_USER							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
 
 #define RFI_TO_USER_OR_KERNEL						\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
 
 #define RFI_TO_GUEST							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
@@ -85,21 +109,25 @@
 	hrfid
 
 #define HRFI_TO_USER							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_USER_OR_KERNEL						\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_GUEST							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_UNKNOWN							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
@@ -225,6 +253,7 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)
 #define __EXCEPTION_PROLOG_1(area, extra, vec)				\
 	OPT_SAVE_REG_TO_PACA(area+EX_PPR, r9, CPU_FTR_HAS_PPR);		\
 	OPT_SAVE_REG_TO_PACA(area+EX_CFAR, r10, CPU_FTR_CFAR);		\
+	INTERRUPT_TO_KERNEL;						\
 	SAVE_CTR(r10, area);						\
 	mfcr	r9;							\
 	extra(vec);							\
diff --git a/arch/powerpc/include/asm/feature-fixups.h b/arch/powerpc/include/asm/feature-fixups.h
index 7b332342071c..0bf8202feca6 100644
--- a/arch/powerpc/include/asm/feature-fixups.h
+++ b/arch/powerpc/include/asm/feature-fixups.h
@@ -189,6 +189,22 @@ void apply_feature_fixups(void);
 void setup_feature_keys(void);
 #endif
 
+#define STF_ENTRY_BARRIER_FIXUP_SECTION			\
+953:							\
+	.pushsection __stf_entry_barrier_fixup,"a";	\
+	.align 2;					\
+954:							\
+	FTR_ENTRY_OFFSET 953b-954b;			\
+	.popsection;
+
+#define STF_EXIT_BARRIER_FIXUP_SECTION			\
+955:							\
+	.pushsection __stf_exit_barrier_fixup,"a";	\
+	.align 2;					\
+956:							\
+	FTR_ENTRY_OFFSET 955b-956b;			\
+	.popsection;
+
 #define RFI_FLUSH_FIXUP_SECTION				\
 951:							\
 	.pushsection __rfi_flush_fixup,"a";		\
@@ -200,6 +216,9 @@ void setup_feature_keys(void);
 
 #ifndef __ASSEMBLY__
 
+extern long stf_barrier_fallback;
+extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
+extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
 extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
 
 #endif
diff --git a/arch/powerpc/include/asm/security_features.h b/arch/powerpc/include/asm/security_features.h
index fa4d2e1cf772..44989b22383c 100644
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -12,6 +12,17 @@
 extern unsigned long powerpc_security_features;
 extern bool rfi_flush;
 
+/* These are bit flags */
+enum stf_barrier_type {
+	STF_BARRIER_NONE	= 0x1,
+	STF_BARRIER_FALLBACK	= 0x2,
+	STF_BARRIER_EIEIO	= 0x4,
+	STF_BARRIER_SYNC_ORI	= 0x8,
+};
+
+void setup_stf_barrier(void);
+void do_stf_barrier_fixups(enum stf_barrier_type types);
+
 static inline void security_ftr_set(unsigned long feature)
 {
 	powerpc_security_features |= feature;
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 94b5dfb087e9..d50cc9b38b80 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -846,7 +846,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
 #endif
 
 
-EXC_REAL_MASKABLE(decrementer, 0x900, 0x980)
+EXC_REAL_OOL_MASKABLE(decrementer, 0x900, 0x980)
 EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x4980, 0x900)
 TRAMP_KVM(PACA_EXGEN, 0x900)
 EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)
@@ -884,6 +884,7 @@ BEGIN_FTR_SECTION						\
 END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
 	mr	r9,r13 ;					\
 	GET_PACA(r13) ;						\
+	INTERRUPT_TO_KERNEL ;					\
 	mfspr	r11,SPRN_SRR0 ;					\
 0:
 
@@ -1353,6 +1354,19 @@ masked_##_H##interrupt:					\
 	##_H##RFI_TO_KERNEL;				\
 	b	.
 
+TRAMP_REAL_BEGIN(stf_barrier_fallback)
+	std	r9,PACA_EXRFI+EX_R9(r13)
+	std	r10,PACA_EXRFI+EX_R10(r13)
+	sync
+	ld	r9,PACA_EXRFI+EX_R9(r13)
+	ld	r10,PACA_EXRFI+EX_R10(r13)
+	ori	31,31,0
+	.rept 14
+	b	1f
+1:
+	.endr
+	blr
+
 /*
  * Real mode exceptions actually use this too, but alternate
  * instruction code patches (which end up in the common .text area)
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index bab5a27ea805..2277df84ef6e 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -5,6 +5,7 @@
 // Copyright 2018, Michael Ellerman, IBM Corporation.
 
 #include <linux/kernel.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/seq_buf.h>
 
@@ -86,3 +87,151 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c
 
 	return s.len;
 }
+
+/*
+ * Store-forwarding barrier support.
+ */
+
+static enum stf_barrier_type stf_enabled_flush_types;
+static bool no_stf_barrier;
+bool stf_barrier;
+
+static int __init handle_no_stf_barrier(char *p)
+{
+	pr_info("stf-barrier: disabled on command line.");
+	no_stf_barrier = true;
+	return 0;
+}
+
+early_param("no_stf_barrier", handle_no_stf_barrier);
+
+/* This is the generic flag used by other architectures */
+static int __init handle_ssbd(char *p)
+{
+	if (!p || strncmp(p, "auto", 5) == 0 || strncmp(p, "on", 2) == 0 ) {
+		/* Until firmware tells us, we have the barrier with auto */
+		return 0;
+	} else if (strncmp(p, "off", 3) == 0) {
+		handle_no_stf_barrier(NULL);
+		return 0;
+	} else
+		return 1;
+
+	return 0;
+}
+early_param("spec_store_bypass_disable", handle_ssbd);
+
+/* This is the generic flag used by other architectures */
+static int __init handle_no_ssbd(char *p)
+{
+	handle_no_stf_barrier(NULL);
+	return 0;
+}
+early_param("nospec_store_bypass_disable", handle_no_ssbd);
+
+static void stf_barrier_enable(bool enable)
+{
+	if (enable)
+		do_stf_barrier_fixups(stf_enabled_flush_types);
+	else
+		do_stf_barrier_fixups(STF_BARRIER_NONE);
+
+	stf_barrier = enable;
+}
+
+void setup_stf_barrier(void)
+{
+	enum stf_barrier_type type;
+	bool enable, hv;
+
+	hv = cpu_has_feature(CPU_FTR_HVMODE);
+
+	/* Default to fallback in case fw-features are not available */
+	if (cpu_has_feature(CPU_FTR_ARCH_300))
+		type = STF_BARRIER_EIEIO;
+	else if (cpu_has_feature(CPU_FTR_ARCH_207S))
+		type = STF_BARRIER_SYNC_ORI;
+	else if (cpu_has_feature(CPU_FTR_ARCH_206))
+		type = STF_BARRIER_FALLBACK;
+	else
+		type = STF_BARRIER_NONE;
+
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+		(security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) ||
+		 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && hv));
+
+	if (type == STF_BARRIER_FALLBACK) {
+		pr_info("stf-barrier: fallback barrier available\n");
+	} else if (type == STF_BARRIER_SYNC_ORI) {
+		pr_info("stf-barrier: hwsync barrier available\n");
+	} else if (type == STF_BARRIER_EIEIO) {
+		pr_info("stf-barrier: eieio barrier available\n");
+	}
+
+	stf_enabled_flush_types = type;
+
+	if (!no_stf_barrier)
+		stf_barrier_enable(enable);
+}
+
+ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (stf_barrier && stf_enabled_flush_types != STF_BARRIER_NONE) {
+		const char *type;
+		switch (stf_enabled_flush_types) {
+		case STF_BARRIER_EIEIO:
+			type = "eieio";
+			break;
+		case STF_BARRIER_SYNC_ORI:
+			type = "hwsync";
+			break;
+		case STF_BARRIER_FALLBACK:
+			type = "fallback";
+			break;
+		default:
+			type = "unknown";
+		}
+		return sprintf(buf, "Mitigation: Kernel entry/exit barrier (%s)\n", type);
+	}
+
+	if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
+	    !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
+		return sprintf(buf, "Not affected\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int stf_barrier_set(void *data, u64 val)
+{
+	bool enable;
+
+	if (val == 1)
+		enable = true;
+	else if (val == 0)
+		enable = false;
+	else
+		return -EINVAL;
+
+	/* Only do anything if we're changing state */
+	if (enable != stf_barrier)
+		stf_barrier_enable(enable);
+
+	return 0;
+}
+
+static int stf_barrier_get(void *data, u64 *val)
+{
+	*val = stf_barrier ? 1 : 0;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_stf_barrier, stf_barrier_get, stf_barrier_set, "%llu\n");
+
+static __init int stf_barrier_debugfs_init(void)
+{
+	debugfs_create_file("stf_barrier", 0600, powerpc_debugfs_root, NULL, &fops_stf_barrier);
+	return 0;
+}
+device_initcall(stf_barrier_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index b61fb7902018..c16fddbb6ab8 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -133,6 +133,20 @@ SECTIONS
 	RODATA
 
 #ifdef CONFIG_PPC64
+	. = ALIGN(8);
+	__stf_entry_barrier_fixup : AT(ADDR(__stf_entry_barrier_fixup) - LOAD_OFFSET) {
+		__start___stf_entry_barrier_fixup = .;
+		*(__stf_entry_barrier_fixup)
+		__stop___stf_entry_barrier_fixup = .;
+	}
+
+	. = ALIGN(8);
+	__stf_exit_barrier_fixup : AT(ADDR(__stf_exit_barrier_fixup) - LOAD_OFFSET) {
+		__start___stf_exit_barrier_fixup = .;
+		*(__stf_exit_barrier_fixup)
+		__stop___stf_exit_barrier_fixup = .;
+	}
+
 	. = ALIGN(8);
 	__rfi_flush_fixup : AT(ADDR(__rfi_flush_fixup) - LOAD_OFFSET) {
 		__start___rfi_flush_fixup = .;
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
index d89d54fa6acc..cf1398e3c2e0 100644
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -22,6 +22,7 @@
 #include <asm/page.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 #include <asm/firmware.h>
 #include <asm/setup.h>
 
@@ -117,6 +118,120 @@ void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
 }
 
 #ifdef CONFIG_PPC_BOOK3S_64
+void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
+{
+	unsigned int instrs[3], *dest;
+	long *start, *end;
+	int i;
+
+	start = PTRRELOC(&__start___stf_entry_barrier_fixup),
+	end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
+
+	instrs[0] = 0x60000000; /* nop */
+	instrs[1] = 0x60000000; /* nop */
+	instrs[2] = 0x60000000; /* nop */
+
+	i = 0;
+	if (types & STF_BARRIER_FALLBACK) {
+		instrs[i++] = 0x7d4802a6; /* mflr r10		*/
+		instrs[i++] = 0x60000000; /* branch patched below */
+		instrs[i++] = 0x7d4803a6; /* mtlr r10		*/
+	} else if (types & STF_BARRIER_EIEIO) {
+		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
+	} else if (types & STF_BARRIER_SYNC_ORI) {
+		instrs[i++] = 0x7c0004ac; /* hwsync		*/
+		instrs[i++] = 0xe94d0000; /* ld r10,0(r13)	*/
+		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+		patch_instruction(dest, instrs[0]);
+
+		if (types & STF_BARRIER_FALLBACK)
+			patch_branch(dest + 1, (unsigned long)&stf_barrier_fallback,
+				     BRANCH_SET_LINK);
+		else
+			patch_instruction(dest + 1, instrs[1]);
+
+		patch_instruction(dest + 2, instrs[2]);
+	}
+
+	printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
+		(types == STF_BARRIER_NONE)                  ? "no" :
+		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
+		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
+		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
+		                                           : "unknown");
+}
+
+void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
+{
+	unsigned int instrs[6], *dest;
+	long *start, *end;
+	int i;
+
+	start = PTRRELOC(&__start___stf_exit_barrier_fixup),
+	end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
+
+	instrs[0] = 0x60000000; /* nop */
+	instrs[1] = 0x60000000; /* nop */
+	instrs[2] = 0x60000000; /* nop */
+	instrs[3] = 0x60000000; /* nop */
+	instrs[4] = 0x60000000; /* nop */
+	instrs[5] = 0x60000000; /* nop */
+
+	i = 0;
+	if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
+		if (cpu_has_feature(CPU_FTR_HVMODE)) {
+			instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
+			instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
+		} else {
+			instrs[i++] = 0x7db243a6; /* mtsprg 2,r13	*/
+			instrs[i++] = 0x7db142a6; /* mfsprg r13,1    */
+	        }
+		instrs[i++] = 0x7c0004ac; /* hwsync		*/
+		instrs[i++] = 0xe9ad0000; /* ld r13,0(r13)	*/
+		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+		if (cpu_has_feature(CPU_FTR_HVMODE)) {
+			instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
+		} else {
+			instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
+		}
+	} else if (types & STF_BARRIER_EIEIO) {
+		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+		patch_instruction(dest, instrs[0]);
+		patch_instruction(dest + 1, instrs[1]);
+		patch_instruction(dest + 2, instrs[2]);
+		patch_instruction(dest + 3, instrs[3]);
+		patch_instruction(dest + 4, instrs[4]);
+		patch_instruction(dest + 5, instrs[5]);
+	}
+	printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
+		(types == STF_BARRIER_NONE)                  ? "no" :
+		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
+		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
+		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
+		                                           : "unknown");
+}
+
+
+void do_stf_barrier_fixups(enum stf_barrier_type types)
+{
+	do_stf_entry_barrier_fixups(types);
+	do_stf_exit_barrier_fixups(types);
+}
+
 void do_rfi_flush_fixups(enum l1d_flush_type types)
 {
 	unsigned int instrs[3], *dest;
diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 2c646f5bd144..17203abf38e8 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -130,6 +130,7 @@ static void __init pnv_setup_arch(void)
 	set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
 
 	pnv_setup_rfi_flush();
+	setup_stf_barrier();
 
 	/* Initialize SMP */
 	pnv_smp_init();
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 7349c05032be..91ade7755823 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -545,6 +545,7 @@ static void __init pSeries_setup_arch(void)
 	fwnmi_init();
 
 	pseries_setup_rfi_flush();
+	setup_stf_barrier();
 
 	/* By default, only probe PCI (can be overridden by rtas_pci) */
 	pci_add_flags(PCI_PROBE_ONLY);
-- 
2.14.1

Patch "powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit" has been added to the 4.9-stable tree

[gregkh]

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

    powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit

to the 4.9-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-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
and it can be found in the queue-4.9 subdirectory.

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


>From foo@baz Sat Jun  2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au>
Date: Sat,  2 Jun 2018 21:09:08 +1000
Subject: powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit
To: gregkh@linuxfoundation.org
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Message-ID: <20180602110908.29773-24-mpe@ellerman.id.au>

From: Nicholas Piggin <npiggin@gmail.com>

commit a048a07d7f4535baa4cbad6bc024f175317ab938 upstream.

On some CPUs we can prevent a vulnerability related to store-to-load
forwarding by preventing store forwarding between privilege domains,
by inserting a barrier in kernel entry and exit paths.

This is known to be the case on at least Power7, Power8 and Power9
powerpc CPUs.

Barriers must be inserted generally before the first load after moving
to a higher privilege, and after the last store before moving to a
lower privilege, HV and PR privilege transitions must be protected.

Barriers are added as patch sections, with all kernel/hypervisor entry
points patched, and the exit points to lower privilge levels patched
similarly to the RFI flush patching.

Firmware advertisement is not implemented yet, so CPU flush types
are hard coded.

Thanks to Michal Suchánek for bug fixes and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/powerpc/include/asm/exception-64s.h     |   29 +++++
 arch/powerpc/include/asm/feature-fixups.h    |   19 +++
 arch/powerpc/include/asm/security_features.h |   11 +
 arch/powerpc/kernel/exceptions-64s.S         |   16 ++
 arch/powerpc/kernel/security.c               |  149 +++++++++++++++++++++++++++
 arch/powerpc/kernel/vmlinux.lds.S            |   14 ++
 arch/powerpc/lib/feature-fixups.c            |  115 ++++++++++++++++++++
 arch/powerpc/platforms/powernv/setup.c       |    1 
 arch/powerpc/platforms/pseries/setup.c       |    1 
 9 files changed, 354 insertions(+), 1 deletion(-)

--- a/arch/powerpc/include/asm/exception-64s.h
+++ b/arch/powerpc/include/asm/exception-64s.h
@@ -51,6 +51,27 @@
 #define EX_PPR		88	/* SMT thread status register (priority) */
 #define EX_CTR		96
 
+#define STF_ENTRY_BARRIER_SLOT						\
+	STF_ENTRY_BARRIER_FIXUP_SECTION;				\
+	nop;								\
+	nop;								\
+	nop
+
+#define STF_EXIT_BARRIER_SLOT						\
+	STF_EXIT_BARRIER_FIXUP_SECTION;					\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop;								\
+	nop
+
+/*
+ * r10 must be free to use, r13 must be paca
+ */
+#define INTERRUPT_TO_KERNEL						\
+	STF_ENTRY_BARRIER_SLOT
+
 /*
  * Macros for annotating the expected destination of (h)rfid
  *
@@ -67,16 +88,19 @@
 	rfid
 
 #define RFI_TO_USER							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
 
 #define RFI_TO_USER_OR_KERNEL						\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
 
 #define RFI_TO_GUEST							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	rfid;								\
 	b	rfi_flush_fallback
@@ -85,21 +109,25 @@
 	hrfid
 
 #define HRFI_TO_USER							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_USER_OR_KERNEL						\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_GUEST							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
 
 #define HRFI_TO_UNKNOWN							\
+	STF_EXIT_BARRIER_SLOT;						\
 	RFI_FLUSH_SLOT;							\
 	hrfid;								\
 	b	hrfi_flush_fallback
@@ -225,6 +253,7 @@ END_FTR_SECTION_NESTED(ftr,ftr,943)
 #define __EXCEPTION_PROLOG_1(area, extra, vec)				\
 	OPT_SAVE_REG_TO_PACA(area+EX_PPR, r9, CPU_FTR_HAS_PPR);		\
 	OPT_SAVE_REG_TO_PACA(area+EX_CFAR, r10, CPU_FTR_CFAR);		\
+	INTERRUPT_TO_KERNEL;						\
 	SAVE_CTR(r10, area);						\
 	mfcr	r9;							\
 	extra(vec);							\
--- a/arch/powerpc/include/asm/feature-fixups.h
+++ b/arch/powerpc/include/asm/feature-fixups.h
@@ -189,6 +189,22 @@ void apply_feature_fixups(void);
 void setup_feature_keys(void);
 #endif
 
+#define STF_ENTRY_BARRIER_FIXUP_SECTION			\
+953:							\
+	.pushsection __stf_entry_barrier_fixup,"a";	\
+	.align 2;					\
+954:							\
+	FTR_ENTRY_OFFSET 953b-954b;			\
+	.popsection;
+
+#define STF_EXIT_BARRIER_FIXUP_SECTION			\
+955:							\
+	.pushsection __stf_exit_barrier_fixup,"a";	\
+	.align 2;					\
+956:							\
+	FTR_ENTRY_OFFSET 955b-956b;			\
+	.popsection;
+
 #define RFI_FLUSH_FIXUP_SECTION				\
 951:							\
 	.pushsection __rfi_flush_fixup,"a";		\
@@ -200,6 +216,9 @@ void setup_feature_keys(void);
 
 #ifndef __ASSEMBLY__
 
+extern long stf_barrier_fallback;
+extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
+extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
 extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
 
 #endif
--- a/arch/powerpc/include/asm/security_features.h
+++ b/arch/powerpc/include/asm/security_features.h
@@ -12,6 +12,17 @@
 extern unsigned long powerpc_security_features;
 extern bool rfi_flush;
 
+/* These are bit flags */
+enum stf_barrier_type {
+	STF_BARRIER_NONE	= 0x1,
+	STF_BARRIER_FALLBACK	= 0x2,
+	STF_BARRIER_EIEIO	= 0x4,
+	STF_BARRIER_SYNC_ORI	= 0x8,
+};
+
+void setup_stf_barrier(void);
+void do_stf_barrier_fixups(enum stf_barrier_type types);
+
 static inline void security_ftr_set(unsigned long feature)
 {
 	powerpc_security_features |= feature;
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -846,7 +846,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
 #endif
 
 
-EXC_REAL_MASKABLE(decrementer, 0x900, 0x980)
+EXC_REAL_OOL_MASKABLE(decrementer, 0x900, 0x980)
 EXC_VIRT_MASKABLE(decrementer, 0x4900, 0x4980, 0x900)
 TRAMP_KVM(PACA_EXGEN, 0x900)
 EXC_COMMON_ASYNC(decrementer_common, 0x900, timer_interrupt)
@@ -884,6 +884,7 @@ BEGIN_FTR_SECTION						\
 END_FTR_SECTION_IFSET(CPU_FTR_REAL_LE)				\
 	mr	r9,r13 ;					\
 	GET_PACA(r13) ;						\
+	INTERRUPT_TO_KERNEL ;					\
 	mfspr	r11,SPRN_SRR0 ;					\
 0:
 
@@ -1353,6 +1354,19 @@ masked_##_H##interrupt:					\
 	##_H##RFI_TO_KERNEL;				\
 	b	.
 
+TRAMP_REAL_BEGIN(stf_barrier_fallback)
+	std	r9,PACA_EXRFI+EX_R9(r13)
+	std	r10,PACA_EXRFI+EX_R10(r13)
+	sync
+	ld	r9,PACA_EXRFI+EX_R9(r13)
+	ld	r10,PACA_EXRFI+EX_R10(r13)
+	ori	31,31,0
+	.rept 14
+	b	1f
+1:
+	.endr
+	blr
+
 /*
  * Real mode exceptions actually use this too, but alternate
  * instruction code patches (which end up in the common .text area)
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -5,6 +5,7 @@
 // Copyright 2018, Michael Ellerman, IBM Corporation.
 
 #include <linux/kernel.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/seq_buf.h>
 
@@ -86,3 +87,151 @@ ssize_t cpu_show_spectre_v2(struct devic
 
 	return s.len;
 }
+
+/*
+ * Store-forwarding barrier support.
+ */
+
+static enum stf_barrier_type stf_enabled_flush_types;
+static bool no_stf_barrier;
+bool stf_barrier;
+
+static int __init handle_no_stf_barrier(char *p)
+{
+	pr_info("stf-barrier: disabled on command line.");
+	no_stf_barrier = true;
+	return 0;
+}
+
+early_param("no_stf_barrier", handle_no_stf_barrier);
+
+/* This is the generic flag used by other architectures */
+static int __init handle_ssbd(char *p)
+{
+	if (!p || strncmp(p, "auto", 5) == 0 || strncmp(p, "on", 2) == 0 ) {
+		/* Until firmware tells us, we have the barrier with auto */
+		return 0;
+	} else if (strncmp(p, "off", 3) == 0) {
+		handle_no_stf_barrier(NULL);
+		return 0;
+	} else
+		return 1;
+
+	return 0;
+}
+early_param("spec_store_bypass_disable", handle_ssbd);
+
+/* This is the generic flag used by other architectures */
+static int __init handle_no_ssbd(char *p)
+{
+	handle_no_stf_barrier(NULL);
+	return 0;
+}
+early_param("nospec_store_bypass_disable", handle_no_ssbd);
+
+static void stf_barrier_enable(bool enable)
+{
+	if (enable)
+		do_stf_barrier_fixups(stf_enabled_flush_types);
+	else
+		do_stf_barrier_fixups(STF_BARRIER_NONE);
+
+	stf_barrier = enable;
+}
+
+void setup_stf_barrier(void)
+{
+	enum stf_barrier_type type;
+	bool enable, hv;
+
+	hv = cpu_has_feature(CPU_FTR_HVMODE);
+
+	/* Default to fallback in case fw-features are not available */
+	if (cpu_has_feature(CPU_FTR_ARCH_300))
+		type = STF_BARRIER_EIEIO;
+	else if (cpu_has_feature(CPU_FTR_ARCH_207S))
+		type = STF_BARRIER_SYNC_ORI;
+	else if (cpu_has_feature(CPU_FTR_ARCH_206))
+		type = STF_BARRIER_FALLBACK;
+	else
+		type = STF_BARRIER_NONE;
+
+	enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
+		(security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) ||
+		 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) && hv));
+
+	if (type == STF_BARRIER_FALLBACK) {
+		pr_info("stf-barrier: fallback barrier available\n");
+	} else if (type == STF_BARRIER_SYNC_ORI) {
+		pr_info("stf-barrier: hwsync barrier available\n");
+	} else if (type == STF_BARRIER_EIEIO) {
+		pr_info("stf-barrier: eieio barrier available\n");
+	}
+
+	stf_enabled_flush_types = type;
+
+	if (!no_stf_barrier)
+		stf_barrier_enable(enable);
+}
+
+ssize_t cpu_show_spec_store_bypass(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	if (stf_barrier && stf_enabled_flush_types != STF_BARRIER_NONE) {
+		const char *type;
+		switch (stf_enabled_flush_types) {
+		case STF_BARRIER_EIEIO:
+			type = "eieio";
+			break;
+		case STF_BARRIER_SYNC_ORI:
+			type = "hwsync";
+			break;
+		case STF_BARRIER_FALLBACK:
+			type = "fallback";
+			break;
+		default:
+			type = "unknown";
+		}
+		return sprintf(buf, "Mitigation: Kernel entry/exit barrier (%s)\n", type);
+	}
+
+	if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
+	    !security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
+		return sprintf(buf, "Not affected\n");
+
+	return sprintf(buf, "Vulnerable\n");
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int stf_barrier_set(void *data, u64 val)
+{
+	bool enable;
+
+	if (val == 1)
+		enable = true;
+	else if (val == 0)
+		enable = false;
+	else
+		return -EINVAL;
+
+	/* Only do anything if we're changing state */
+	if (enable != stf_barrier)
+		stf_barrier_enable(enable);
+
+	return 0;
+}
+
+static int stf_barrier_get(void *data, u64 *val)
+{
+	*val = stf_barrier ? 1 : 0;
+	return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(fops_stf_barrier, stf_barrier_get, stf_barrier_set, "%llu\n");
+
+static __init int stf_barrier_debugfs_init(void)
+{
+	debugfs_create_file("stf_barrier", 0600, powerpc_debugfs_root, NULL, &fops_stf_barrier);
+	return 0;
+}
+device_initcall(stf_barrier_debugfs_init);
+#endif /* CONFIG_DEBUG_FS */
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -134,6 +134,20 @@ SECTIONS
 
 #ifdef CONFIG_PPC64
 	. = ALIGN(8);
+	__stf_entry_barrier_fixup : AT(ADDR(__stf_entry_barrier_fixup) - LOAD_OFFSET) {
+		__start___stf_entry_barrier_fixup = .;
+		*(__stf_entry_barrier_fixup)
+		__stop___stf_entry_barrier_fixup = .;
+	}
+
+	. = ALIGN(8);
+	__stf_exit_barrier_fixup : AT(ADDR(__stf_exit_barrier_fixup) - LOAD_OFFSET) {
+		__start___stf_exit_barrier_fixup = .;
+		*(__stf_exit_barrier_fixup)
+		__stop___stf_exit_barrier_fixup = .;
+	}
+
+	. = ALIGN(8);
 	__rfi_flush_fixup : AT(ADDR(__rfi_flush_fixup) - LOAD_OFFSET) {
 		__start___rfi_flush_fixup = .;
 		*(__rfi_flush_fixup)
--- a/arch/powerpc/lib/feature-fixups.c
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -22,6 +22,7 @@
 #include <asm/page.h>
 #include <asm/sections.h>
 #include <asm/setup.h>
+#include <asm/security_features.h>
 #include <asm/firmware.h>
 #include <asm/setup.h>
 
@@ -117,6 +118,120 @@ void do_feature_fixups(unsigned long val
 }
 
 #ifdef CONFIG_PPC_BOOK3S_64
+void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
+{
+	unsigned int instrs[3], *dest;
+	long *start, *end;
+	int i;
+
+	start = PTRRELOC(&__start___stf_entry_barrier_fixup),
+	end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
+
+	instrs[0] = 0x60000000; /* nop */
+	instrs[1] = 0x60000000; /* nop */
+	instrs[2] = 0x60000000; /* nop */
+
+	i = 0;
+	if (types & STF_BARRIER_FALLBACK) {
+		instrs[i++] = 0x7d4802a6; /* mflr r10		*/
+		instrs[i++] = 0x60000000; /* branch patched below */
+		instrs[i++] = 0x7d4803a6; /* mtlr r10		*/
+	} else if (types & STF_BARRIER_EIEIO) {
+		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
+	} else if (types & STF_BARRIER_SYNC_ORI) {
+		instrs[i++] = 0x7c0004ac; /* hwsync		*/
+		instrs[i++] = 0xe94d0000; /* ld r10,0(r13)	*/
+		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+		patch_instruction(dest, instrs[0]);
+
+		if (types & STF_BARRIER_FALLBACK)
+			patch_branch(dest + 1, (unsigned long)&stf_barrier_fallback,
+				     BRANCH_SET_LINK);
+		else
+			patch_instruction(dest + 1, instrs[1]);
+
+		patch_instruction(dest + 2, instrs[2]);
+	}
+
+	printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
+		(types == STF_BARRIER_NONE)                  ? "no" :
+		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
+		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
+		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
+		                                           : "unknown");
+}
+
+void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
+{
+	unsigned int instrs[6], *dest;
+	long *start, *end;
+	int i;
+
+	start = PTRRELOC(&__start___stf_exit_barrier_fixup),
+	end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
+
+	instrs[0] = 0x60000000; /* nop */
+	instrs[1] = 0x60000000; /* nop */
+	instrs[2] = 0x60000000; /* nop */
+	instrs[3] = 0x60000000; /* nop */
+	instrs[4] = 0x60000000; /* nop */
+	instrs[5] = 0x60000000; /* nop */
+
+	i = 0;
+	if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
+		if (cpu_has_feature(CPU_FTR_HVMODE)) {
+			instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
+			instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
+		} else {
+			instrs[i++] = 0x7db243a6; /* mtsprg 2,r13	*/
+			instrs[i++] = 0x7db142a6; /* mfsprg r13,1    */
+	        }
+		instrs[i++] = 0x7c0004ac; /* hwsync		*/
+		instrs[i++] = 0xe9ad0000; /* ld r13,0(r13)	*/
+		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
+		if (cpu_has_feature(CPU_FTR_HVMODE)) {
+			instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
+		} else {
+			instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
+		}
+	} else if (types & STF_BARRIER_EIEIO) {
+		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
+	}
+
+	for (i = 0; start < end; start++, i++) {
+		dest = (void *)start + *start;
+
+		pr_devel("patching dest %lx\n", (unsigned long)dest);
+
+		patch_instruction(dest, instrs[0]);
+		patch_instruction(dest + 1, instrs[1]);
+		patch_instruction(dest + 2, instrs[2]);
+		patch_instruction(dest + 3, instrs[3]);
+		patch_instruction(dest + 4, instrs[4]);
+		patch_instruction(dest + 5, instrs[5]);
+	}
+	printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
+		(types == STF_BARRIER_NONE)                  ? "no" :
+		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
+		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
+		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
+		                                           : "unknown");
+}
+
+
+void do_stf_barrier_fixups(enum stf_barrier_type types)
+{
+	do_stf_entry_barrier_fixups(types);
+	do_stf_exit_barrier_fixups(types);
+}
+
 void do_rfi_flush_fixups(enum l1d_flush_type types)
 {
 	unsigned int instrs[3], *dest;
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -130,6 +130,7 @@ static void __init pnv_setup_arch(void)
 	set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
 
 	pnv_setup_rfi_flush();
+	setup_stf_barrier();
 
 	/* Initialize SMP */
 	pnv_smp_init();
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -545,6 +545,7 @@ static void __init pSeries_setup_arch(vo
 	fwnmi_init();
 
 	pseries_setup_rfi_flush();
+	setup_stf_barrier();
 
 	/* By default, only probe PCI (can be overridden by rtas_pci) */
 	pci_add_flags(PCI_PROBE_ONLY);


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

queue-4.9/powerpc-64s-clear-pcr-on-boot.patch
queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch
queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch
queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch
queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch
queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch
queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch
queue-4.9/powerpc-move-default-security-feature-flags.patch
queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch
queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch
queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch
queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch
queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch
queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch
queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch
queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch
queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch
queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch
queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch
queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch

Re: [PATCH stable 4.9 00/23] powerpc backports for 4.9

[Greg KH]

On Sat, Jun 02, 2018 at 09:08:45PM +1000, Michael Ellerman wrote:
> Hi Greg,
> 
> Please queue up this series of patches for 4.9 if you have no objections.
> 
> The first one is not a backport but a fix for a previous backport.

Looks good, all now queued up, thanks.

greg k-h

Re: [PATCH stable 4.9 00/23] powerpc backports for 4.9

[Michael Ellerman]

Greg KH <gregkh@linuxfoundation.org> writes:

> On Sat, Jun 02, 2018 at 09:08:45PM +1000, Michael Ellerman wrote:
>> Hi Greg,
>> 
>> Please queue up this series of patches for 4.9 if you have no objections.
>> 
>> The first one is not a backport but a fix for a previous backport.
>
> Looks good, all now queued up, thanks.

Thanks.

cheers