This is a note to let you know that I've just added the patch titled
powerpc/fsl: Flush branch predictor when entering KVM
to the 4.19-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-fsl-flush-branch-predictor-when-entering-kvm.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
>From foo@baz Fri Mar 29 16:04:51 CET 2019
From: Michael Ellerman <[email protected]>
Date: Fri, 29 Mar 2019 22:26:15 +1100
Subject: powerpc/fsl: Flush branch predictor when entering KVM
To: [email protected], [email protected]
Cc: [email protected], [email protected], [email protected],
[email protected]
Message-ID: <[email protected]>
From: Diana Craciun <[email protected]>
commit e7aa61f47b23afbec41031bc47ca8d6cb6516abc upstream.
Switching from the guest to host is another place
where the speculative accesses can be exploited.
Flush the branch predictor when entering KVM.
Signed-off-by: Diana Craciun <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
arch/powerpc/kvm/bookehv_interrupts.S | 4 ++++
1 file changed, 4 insertions(+)
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -75,6 +75,10 @@
PPC_LL r1, VCPU_HOST_STACK(r4)
PPC_LL r2, HOST_R2(r1)
+START_BTB_FLUSH_SECTION
+ BTB_FLUSH(r10)
+END_BTB_FLUSH_SECTION
+
mfspr r10, SPRN_PID
lwz r8, VCPU_HOST_PID(r4)
PPC_LL r11, VCPU_SHARED(r4)
Patches currently in stable-queue which might be from [email protected] are
queue-4.19/powerpc-fsl-emulate-sprn_bucsr-register.patch
queue-4.19/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-64bit.patch
queue-4.19/powerpc-fsl-update-spectre-v2-reporting.patch
queue-4.19/powerpc-fsl-add-macro-to-flush-the-branch-predictor.patch
queue-4.19/powerpc-security-fix-spectre_v2-reporting.patch
queue-4.19/powerpc-fsl-fix-the-flush-of-branch-predictor.patch
queue-4.19/powerpc-fsl-enable-runtime-patching-if-nospectre_v2-boot-arg-is-used.patch
queue-4.19/powerpc-fsl-fixed-warning-orphan-section-__btb_flush_fixup.patch
queue-4.19/powerpc-fsl-add-nospectre_v2-command-line-argument.patch
queue-4.19/powerpc-fsl-add-infrastructure-to-fixup-branch-predictor-flush.patch
queue-4.19/powerpc-fsl-flush-the-branch-predictor-at-each-kernel-entry-32-bit.patch
queue-4.19/powerpc-fsl-flush-branch-predictor-when-entering-kvm.patch
