arm64: Allow CPUs unffected by ARM erratum 1418040 to come in late
PATCH 1/1 arm64: Allow CPUs unffected by ARM erratum 1418040 to come in late
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.
--- arch/arm64/kernel/cpu_errata.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
arch/arm64/kernel/cpu_errata.c +6 -2
@@ -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
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Quoted 22 lines · Marc Zyngier
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 toARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE.Reported-by Doug Anderson <[email protected]>Tested-by Sai Prakash Ranjan <[email protected]>Fixes bf87bb0881d0 ("arm64: Allow booting of late CPUs affected by erratum 1418040")Signed-off-by Marc Zyngier <[email protected]>--- arch/arm64/kernel/cpu_errata.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)arch/arm64/kernel/cpu_errata.c +0
-0@@ -910,8 +910,12 @@ const struct arm64_cpu_capabilities arm64_errata[] = { .desc = "ARM erratum 1418040",
arch/arm64/kernel/cpu_errata.c const struct arm64_cpu_capabilities arm64_errata[] = { · line 918
Quoted 10 lines
arch/arm64/kernel/cpu_errata.c +6
-2.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,
Will
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Quoted 5 lines · Marc Zyngier
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).
Quoted 7 lines
To allow this, we need to add
ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU, which amounts to set .type toARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE.Reported-by Doug Anderson <[email protected]>Tested-by Sai Prakash Ranjan <[email protected]>Fixes bf87bb0881d0 ("arm64: Allow booting of late CPUs affected by erratum 1418040")Signed-off-by Marc Zyngier <[email protected]>
And I guess I deserve brownie points for having found the problem initially and identified the offending commit, even though it was Doug who reported it to the list :)
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Hi,
Quoted 15 lines · Matthias Kaehlcke
Quoted 5 lines · Marc Zyngier
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).
Quoted 7 lines
To allow this, we need to add
ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU, which amounts to set .type toARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE.Reported-by Doug Anderson <[email protected]>Tested-by Sai Prakash Ranjan <[email protected]>Fixes bf87bb0881d0 ("arm64: Allow booting of late CPUs affected by erratum 1418040")Signed-off-by Marc Zyngier <[email protected]>
Quoted 7 lines
Tested-by Matthias Kaehlcke <[email protected]>And I guess I deserve brownie points for having found the problem initially and identified the offending commit, even though it was Doug who reported it to the list :)
Reported-by Matthias Kaehlcke <[email protected]>
LOL, I was just thinking that. Feel free to just use Matthias's Reported-by and leave mine off. I don't think my contributions here are enough to warrant a tag. ;-)
-Doug
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