Patch "powerpc/64s: Enhance the information in cpu_show_meltdown()" has been added to the 4.9-stable tree
From: <gregkh@linuxfoundation.org>
Date: 2018-06-02 13:36:45
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 [off-list ref] 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: [ref] 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