This is a note to let you know that I've just added the patch titled
[PATCH stable v4.14 05/32] powerpc/64: Use barrier_nospec in syscall entry 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-64-use-barrier_nospec-in-syscall-entry.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 <sta...@vger.kernel.org> know about it. >From foo@baz Fri Mar 29 15:53:50 CET 2019 From: Michael Ellerman <m...@ellerman.id.au> Date: Fri, 29 Mar 2019 22:25:53 +1100 Subject: [PATCH stable v4.14 05/32] powerpc/64: Use barrier_nospec in syscall entry To: sta...@vger.kernel.org, gre...@linuxfoundation.org Cc: linuxppc-...@ozlabs.org, diana.crac...@nxp.com, msucha...@suse.de, christophe.le...@c-s.fr Message-ID: <20190329112620.14489-6-...@ellerman.id.au> From: Michael Ellerman <m...@ellerman.id.au> commit 51973a815c6b46d7b23b68d6af371ad1c9d503ca upstream. Our syscall entry is done in assembly so patch in an explicit barrier_nospec. Based on a patch by Michal Suchanek. Signed-off-by: Michal Suchanek <msucha...@suse.de> Signed-off-by: Michael Ellerman <m...@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/powerpc/kernel/entry_64.S | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -36,6 +36,7 @@ #include <asm/context_tracking.h> #include <asm/tm.h> #include <asm/ppc-opcode.h> +#include <asm/barrier.h> #include <asm/export.h> #ifdef CONFIG_PPC_BOOK3S #include <asm/exception-64s.h> @@ -179,6 +180,15 @@ system_call: /* label this so stack tr clrldi r8,r8,32 15: slwi r0,r0,4 + + barrier_nospec_asm + /* + * Prevent the load of the handler below (based on the user-passed + * system call number) being speculatively executed until the test + * against NR_syscalls and branch to .Lsyscall_enosys above has + * committed. + */ + ldx r12,r11,r0 /* Fetch system call handler [ptr] */ mtctr r12 bctrl /* Call handler */ Patches currently in stable-queue which might be from m...@ellerman.id.au are queue-4.14/powerpc-fsl-emulate-sprn_bucsr-register.patch queue-4.14/powerpc-64-make-stf-barrier-ppc_book3s_64-specific.patch queue-4.14/powerpc-fsl-fix-spectre_v2-mitigations-reporting.patch queue-4.14/powerpc-64s-patch-barrier_nospec-in-modules.patch queue-4.14/powerpc-pseries-query-hypervisor-for-count-cache-flush-settings.patch queue-4.14/powerpc-64s-add-support-for-software-count-cache-flush.patch queue-4.14/powerpc64s-show-ori31-availability-in-spectre_v1-sysfs-file-not-v2.patch queue-4.14/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-64bit.patch queue-4.14/powerpc-fsl-update-spectre-v2-reporting.patch queue-4.14/powerpc-64-make-meltdown-reporting-book3s-64-specific.patch queue-4.14/powerpc-64s-add-support-for-ori-barrier_nospec-patching.patch queue-4.14/powerpc-use-barrier_nospec-in-copy_from_user.patch queue-4.14/powerpc-fsl-sanitize-the-syscall-table-for-nxp-powerpc-32-bit-platforms.patch queue-4.14/powerpc-fsl-add-macro-to-flush-the-branch-predictor.patch queue-4.14/powerpc-fsl-add-barrier_nospec-implementation-for-nxp-powerpc-book3e.patch queue-4.14/powerpc-security-fix-spectre_v2-reporting.patch queue-4.14/powerpc-64-disable-the-speculation-barrier-from-the-command-line.patch queue-4.14/powerpc-fsl-fix-the-flush-of-branch-predictor.patch queue-4.14/powerpc-64-add-config_ppc_barrier_nospec.patch queue-4.14/powerpc-fsl-enable-runtime-patching-if-nospectre_v2-boot-arg-is-used.patch queue-4.14/powerpc-64-use-barrier_nospec-in-syscall-entry.patch queue-4.14/powerpc-fsl-fixed-warning-orphan-section-__btb_flush_fixup.patch queue-4.14/powerpc-fsl-add-nospectre_v2-command-line-argument.patch queue-4.14/powerpc-64s-add-new-security-feature-flags-for-count-cache-flush.patch queue-4.14/powerpc-fsl-add-infrastructure-to-fixup-branch-predictor-flush.patch queue-4.14/powerpc-64s-enhance-the-information-in-cpu_show_spectre_v1.patch queue-4.14/powerpc-64-call-setup_barrier_nospec-from-setup_arch.patch queue-4.14/powerpc-asm-add-a-patch_site-macro-helpers-for-patching-instructions.patch queue-4.14/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-32-bit.patch queue-4.14/powerpc-64s-enable-barrier_nospec-based-on-firmware-settings.patch queue-4.14/powerpc-fsl-flush-branch-predictor-when-entering-kvm.patch queue-4.14/powerpc-powernv-query-firmware-for-count-cache-flush-settings.patch