arm64: Allow CPUs unffected by ARM erratum 1418040 to come in late

[ 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 <mka@chromium.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200911181611.2073183-1-maz@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index 2c0b82db825bad2d8005c4fbf3ea0ee2f3cd0a93..422ed2e38a6c848c068bd2216bbe68730a113bc9 100644 (file)
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -910,8 +910,12 @@ 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_WORKAROUND_SPECULATIVE_AT