@@ -822,9 +822,6 @@ 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);
@@ -878,13 +875,19 @@ 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;
}
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 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@vger.kernel.org> know about it. From foo@baz Sun May 27 15:47:18 CEST 2018 From: Michael Ellerman <mpe@ellerman.id.au> Date: Sat, 26 May 2018 14:27:30 +1000 Subject: powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code To: greg@kroah.com Cc: stable@vger.kernel.org, tglx@linutronix.de, linuxppc-dev@ozlabs.org Message-ID: <20180526042749.5324-5-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(-) Patches currently in stable-queue which might be from mpe@ellerman.id.au are queue-4.14/powerpc-64s-clear-pcr-on-boot.patch queue-4.14/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch queue-4.14/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch queue-4.14/powerpc-pseries-fix-clearing-of-security-feature-flags.patch queue-4.14/powerpc-powernv-set-or-clear-security-feature-flags.patch queue-4.14/powerpc-64s-move-cpu_show_meltdown.patch queue-4.14/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch queue-4.14/powerpc-pseries-set-or-clear-security-feature-flags.patch queue-4.14/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch queue-4.14/powerpc-move-default-security-feature-flags.patch queue-4.14/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch queue-4.14/powerpc-add-security-feature-flags-for-spectre-meltdown.patch queue-4.14/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch queue-4.14/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch queue-4.14/powerpc-64s-improve-rfi-l1-d-cache-flush-fallback.patch queue-4.14/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch queue-4.14/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch queue-4.14/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch queue-4.14/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch queue-4.14/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch queue-4.14/powerpc-64s-wire-up-cpu_show_spectre_v1.patch queue-4.14/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch queue-4.14/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch queue-4.14/powerpc-64s-wire-up-cpu_show_spectre_v2.patch