This is a note to let you know that I've just added the patch titled
[PATCH 22/27] powerpc/speculation: Support 'mitigations=' cmdline
to the 5.0-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:
0022-powerpc-speculation-Support-mitigations-cmdline-opti.patch
and it can be found in the queue-5.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <sta...@vger.kernel.org> know about it.
>From fd08ca316946b321be1a86b8fcc4ed8decd0c6a2 Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoim...@redhat.com>
Date: Fri, 12 Apr 2019 15:39:30 -0500
Subject: [PATCH 22/27] powerpc/speculation: Support 'mitigations=' cmdline
option
commit 782e69efb3dfed6e8360bc612e8c7827a901a8f9 upstream
Configure powerpc CPU runtime speculation bug mitigations in accordance
with the 'mitigations=' cmdline option. This affects Meltdown, Spectre
v1, Spectre v2, and Speculative Store Bypass.
The default behavior is unchanged.
Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com>
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Tested-by: Jiri Kosina <jkos...@suse.cz> (on x86)
Reviewed-by: Jiri Kosina <jkos...@suse.cz>
Cc: Borislav Petkov <b...@alien8.de>
Cc: "H . Peter Anvin" <h...@zytor.com>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Jiri Kosina <ji...@kernel.org>
Cc: Waiman Long <long...@redhat.com>
Cc: Andrea Arcangeli <aarca...@redhat.com>
Cc: Jon Masters <j...@redhat.com>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Martin Schwidefsky <schwidef...@de.ibm.com>
Cc: Heiko Carstens <heiko.carst...@de.ibm.com>
Cc: linux-s...@vger.kernel.org
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: Will Deacon <will.dea...@arm.com>
Cc: linux-arm-ker...@lists.infradead.org
Cc: linux-a...@vger.kernel.org
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Tyler Hicks <tyhi...@canonical.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Randy Dunlap <rdun...@infradead.org>
Cc: Steven Price <steven.pr...@arm.com>
Cc: Phil Auld <pa...@redhat.com>
Link:
https://lkml.kernel.org/r/245a606e1a42a558a310220312d9b6adb9159df6.1555085500.git.jpoim...@redhat.com
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
Documentation/admin-guide/kernel-parameters.txt | 9 +++++----
arch/powerpc/kernel/security.c | 6 +++---
arch/powerpc/kernel/setup_64.c | 2 +-
3 files changed, 9 insertions(+), 8 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt
b/Documentation/admin-guide/kernel-parameters.txt
index 59a1181e52b8..ed9ec2ea362d 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2540,7 +2540,7 @@
http://repo.or.cz/w/linux-2.6/mini2440.git
mitigations=
- [X86] Control optional mitigations for CPU
+ [X86,PPC] Control optional mitigations for CPU
vulnerabilities. This is a set of curated,
arch-independent options, each of which is an
aggregation of existing arch-specific options.
@@ -2549,10 +2549,11 @@
Disable all optional CPU mitigations. This
improves system performance, but it may also
expose users to several CPU vulnerabilities.
- Equivalent to: nopti [X86]
- nospectre_v2 [X86]
+ Equivalent to: nopti [X86,PPC]
+ nospectre_v1 [PPC]
+ nospectre_v2 [X86,PPC]
spectre_v2_user=off [X86]
- spec_store_bypass_disable=off
[X86]
+ spec_store_bypass_disable=off
[X86,PPC]
l1tf=off [X86]
auto (default)
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index b33bafb8fcea..70568ccbd9fd 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -57,7 +57,7 @@ void setup_barrier_nospec(void)
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR);
- if (!no_nospec)
+ if (!no_nospec && !cpu_mitigations_off())
enable_barrier_nospec(enable);
}
@@ -116,7 +116,7 @@ static int __init handle_nospectre_v2(char *p)
early_param("nospectre_v2", handle_nospectre_v2);
void setup_spectre_v2(void)
{
- if (no_spectrev2)
+ if (no_spectrev2 || cpu_mitigations_off())
do_btb_flush_fixups();
else
btb_flush_enabled = true;
@@ -300,7 +300,7 @@ void setup_stf_barrier(void)
stf_enabled_flush_types = type;
- if (!no_stf_barrier)
+ if (!no_stf_barrier && !cpu_mitigations_off())
stf_barrier_enable(enable);
}
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 236c1151a3a7..c7ec27ba8926 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -958,7 +958,7 @@ void setup_rfi_flush(enum l1d_flush_type types, bool enable)
enabled_flush_types = types;
- if (!no_rfi_flush)
+ if (!no_rfi_flush && !cpu_mitigations_off())
rfi_flush_enable(enable);
}
--
2.21.0
Patches currently in stable-queue which might be from jpoim...@redhat.com are
queue-5.0/0019-x86-speculation-mds-Print-SMT-vulnerable-on-MSBDS-wi.patch
queue-5.0/0016-x86-speculation-Move-arch_smt_update-call-to-after-m.patch
queue-5.0/0024-x86-speculation-mds-Add-mitigations-support-for-MDS.patch
queue-5.0/0021-x86-speculation-Support-mitigations-cmdline-option.patch
queue-5.0/0022-powerpc-speculation-Support-mitigations-cmdline-opti.patch
queue-5.0/0020-cpu-speculation-Add-mitigations-cmdline-option.patch
queue-5.0/0023-s390-speculation-Support-mitigations-cmdline-option.patch
queue-5.0/0015-x86-speculation-mds-Add-mds-full-nosmt-cmdline-optio.patch
queue-5.0/0027-x86-speculation-mds-Fix-documentation-typo.patch
queue-5.0/0017-x86-speculation-mds-Add-SMT-warning-message.patch
queue-5.0/0018-x86-speculation-mds-Fix-comment.patch
