Patch "[PATCH 28/32] s390/speculation: Support 'mitigations=' cmdline option" has been added to the 4.14-stable tree
Subsystems (2)
[email protected]
AppliedThis is a note to let you know that I've just added the patch titled
[PATCH 28/32] s390/speculation: Support 'mitigations=' cmdline option
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:
0028-s390-speculation-Support-mitigations-cmdline-option.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 <[email protected]> know about it.
From fd823d678f3cdc35d423a25e6ce9a7c0d2e55e1b Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <[email protected]>
Date: Fri, 12 Apr 2019 15:39:31 -0500
Subject: [PATCH 28/32] s390/speculation: Support 'mitigations=' cmdline option
commit 0336e04a6520bdaefdb0769d2a70084fa52e81ed upstream
Configure s390 runtime CPU speculation bug mitigations in accordance with the 'mitigations=' cmdline option. This affects Spectre v1 and Spectre v2.
The default behavior is unchanged.
--- Documentation/admin-guide/kernel-parameters.txt | 5 +++-- arch/s390/kernel/nospec-branch.c | 9 +++++++++ 2 files changed, 12 insertions(+), 2 deletions(-)
Documentation/admin-guide/kernel-parameters.txt +3 -2
@@ -2389,7 +2389,7 @@ http://repo.or.cz/w/linux-2.6/mini2440.git mitigations= - [X86,PPC] Control optional mitigations for CPU + [X86,PPC,S390] 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.
@@ -2400,7 +2400,8 @@ expose users to several CPU vulnerabilities. Equivalent to: nopti [X86,PPC] nospectre_v1 [PPC] - nospectre_v2 [X86,PPC] + nobp=0 [S390] + nospectre_v2 [X86,PPC,S390] spectre_v2_user=off [X86] spec_store_bypass_disable=off [X86,PPC] l1tf=off [X86]
arch/s390/kernel/nospec-branch.c +9 -0
@@ -1,6 +1,7 @@// SPDX-License-Identifier: GPL-2.0 #include <linux/module.h> #include <linux/device.h> +#include <linux/cpu.h> #include <asm/facility.h> #include <asm/nospec-branch.h>
@@ -55,8 +56,16 @@ static int __init nospectre_v2_setup_early(char *str) }early_param ("nospectre_v2" , nospectre_v2_setup_early); +void __init nospec_auto_detect (void ) { +if (cpu_mitigations_off ()) { +/* +* Disable expolines and disable nobp. +*/ +if (IS_ENABLED (CC_USING_EXPOLINE )) + nospec_disable =1 ; +__clear_facility (82 , S390_lowcore.alt_stfle_fac_list);if (IS_ENABLED (CC_USING_EXPOLINE )) {/* * The kernel has been compiled with expolines.
Signature · 23 lines
2.21.0 Patches currently in stable-queue which might be from [email protected] are queue-4.14/0022-x86-speculation-mds-Add-SMT-warning-message.patch queue-4.14/0027-powerpc-speculation-Support-mitigations-cmdline-opti.patch queue-4.14/0025-cpu-speculation-Add-mitigations-cmdline-option.patch queue-4.14/0029-x86-speculation-mds-Add-mitigations-support-for-MDS.patch queue-4.14/0028-s390-speculation-Support-mitigations-cmdline-option.patch queue-4.14/0032-x86-speculation-mds-Fix-documentation-typo.patch queue-4.14/0023-x86-speculation-mds-Fix-comment.patch queue-4.14/0002-Documentation-l1tf-Fix-small-spelling-typo.patch queue-4.14/0024-x86-speculation-mds-Print-SMT-vulnerable-on-MSBDS-wi.patch queue-4.14/0026-x86-speculation-Support-mitigations-cmdline-option.patch queue-4.14/0021-x86-speculation-Move-arch_smt_update-call-to-after-m.patch queue-4.14/0020-x86-speculation-mds-Add-mds-full-nosmt-cmdline-optio.patch _______________________________________________ linux-arm-kernel mailing list [email protected] http://lists.infradead.org/mailman/listinfo/linux-arm-kernel