This is a note to let you know that I've just added the patch titled
[Variant 2/Spectre-v2] arm64: Run enable method for errata work arounds on late CPUs
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: arm64-run-enable-method-for-errata-work-arounds-on-late-cpus.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 stable@vger.kernel.org know about it.
From foo@baz Wed Feb 14 14:44:54 CET 2018
From: Suzuki K Poulose suzuki.poulose@arm.com Date: Wed, 17 Jan 2018 17:42:20 +0000 Subject: [Variant 2/Spectre-v2] arm64: Run enable method for errata work arounds on late CPUs
From: Suzuki K Poulose suzuki.poulose@arm.com
Commit 55b35d070c25 upstream.
When a CPU is brought up after we have finalised the system wide capabilities (i.e, features and errata), we make sure the new CPU doesn't need a new errata work around which has not been detected already. However we don't run enable() method on the new CPU for the errata work arounds already detected. This could cause the new CPU running without potential work arounds. It is upto the "enable()" method to decide if this CPU should do something about the errata.
Fixes: commit 6a6efbb45b7d95c84 ("arm64: Verify CPU errata work arounds on hotplugged CPU") Cc: Will Deacon will.deacon@arm.com Cc: Mark Rutland mark.rutland@arm.com Cc: Andre Przywara andre.przywara@arm.com Cc: Dave Martin dave.martin@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: Ard Biesheuvel ard.biesheuvel@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/kernel/cpu_errata.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
--- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -221,15 +221,18 @@ void verify_local_cpu_errata_workarounds { const struct arm64_cpu_capabilities *caps = arm64_errata;
- for (; caps->matches; caps++) - if (!cpus_have_cap(caps->capability) && - caps->matches(caps, SCOPE_LOCAL_CPU)) { + for (; caps->matches; caps++) { + if (cpus_have_cap(caps->capability)) { + if (caps->enable) + caps->enable((void *)caps); + } else if (caps->matches(caps, SCOPE_LOCAL_CPU)) { pr_crit("CPU%d: Requires work around for %s, not detected" " at boot time\n", smp_processor_id(), caps->desc ? : "an erratum"); cpu_die_early(); } + } }
void update_cpu_errata_workarounds(void)
Patches currently in stable-queue which might be from suzuki.poulose@arm.com are
queue-4.14/arm64-cpufeature-pass-capability-structure-to-enable-callback.patch queue-4.14/arm64-capabilities-handle-duplicate-entries-for-a-capability.patch queue-4.14/arm64-take-into-account-id_aa64pfr0_el1.csv3.patch queue-4.14/arm64-run-enable-method-for-errata-work-arounds-on-late-cpus.patch queue-4.14/arm64-cpufeature-__this_cpu_has_cap-shouldn-t-stop-early.patch