From: Marc Zyngier <m...@kernel.org>

[ Upstream commit ed888cb0d1ebce69f12794e89fbd5e2c86d40b8d ]

Now that we allow CPUs affected by erratum 1418040 to come in late,
this prevents their unaffected sibblings from coming in late (or
coming back after a suspend or hotplug-off, which amounts to the
same thing).

To allow this, we need to add ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU,
which amounts to set .type to ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE.

Fixes: bf87bb0881d0 ("arm64: Allow booting of late CPUs affected by erratum 
1418040")
Reported-by: Matthias Kaehlcke <m...@chromium.org>
Signed-off-by: Marc Zyngier <m...@kernel.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ran...@codeaurora.org>
Tested-by: Matthias Kaehlcke <m...@chromium.org>
Acked-by: Will Deacon <w...@kernel.org>
Link: https://lore.kernel.org/r/20200911181611.2073183-1-...@kernel.org
Signed-off-by: Catalin Marinas <catalin.mari...@arm.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 arch/arm64/kernel/cpu_errata.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 51462c59ab5da..d2e738c455566 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -917,8 +917,12 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
                .desc = "ARM erratum 1418040",
                .capability = ARM64_WORKAROUND_1418040,
                ERRATA_MIDR_RANGE_LIST(erratum_1418040_list),
-               .type = (ARM64_CPUCAP_SCOPE_LOCAL_CPU |
-                        ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU),
+               /*
+                * We need to allow affected CPUs to come in late, but
+                * also need the non-affected CPUs to be able to come
+                * in at any point in time. Wonderful.
+                */
+               .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE,
        },
 #endif
 #ifdef CONFIG_ARM64_ERRATUM_1165522
-- 
2.25.1



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