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

[<gregkh@linuxfoundation.org>]

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