On Fri, Jan 26, 2018 at 12:21:43PM +0000, Suzuki K Poulose wrote:

On 26/01/18 11:22, Dave Martin wrote:

quoted

On Tue, Jan 23, 2018 at 12:28:00PM +0000, Suzuki K Poulose wrote:

quoted

While processing the list of capabilities, it is useful to
filter out some of the entries based on the given type to
allow better control. This can be used later for handling
LOCAL vs SYSTEM wide capabilities and more.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 arch/arm64/include/asm/cpufeature.h |  5 +++++
 arch/arm64/kernel/cpufeature.c      | 30 ++++++++++++++++++++----------
 2 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 27d037bb0451..a621d2184227 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h

@@ -99,6 +99,11 @@ extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0;
 /* Is it safe for a late CPU to miss this capability when system has it */
 #define ARM64_CPUCAP_LATE_CPU_SAFE_TO_MISS	BIT(3)
+#define ARM64_CPUCAP_TYPE_ALL			 \
+	(ARM64_CPUCAP_SCOPE_LOCAL_CPU		|\
+	 ARM64_CPUCAP_SCOPE_SYSTEM		|\
+	 ARM64_CPUCAP_LATE_CPU_SAFE_TO_HAVE	|\
+	 ARM64_CPUCAP_LATE_CPU_SAFE_TO_MISS)

Nit: can we have another tab between | and \?

This will help to make missing |s stand out more if/when more entries
are added to this list in future.

Sure, will do.

quoted

quoted

 /*
  * CPU errata detected at boot time based on feature of one or more CPUs.
  * It is not safe for a late CPU to have this feature when the system doesn't

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c

[...]

quoted

quoted

@@ -1204,12 +1206,13 @@ static int __enable_cpu_capability(void *arg)
  * Run through the enabled capabilities and enable() it on all active
  * CPUs
  */
-static void __init enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps)
+static void __init
+enable_cpu_capabilities(const struct arm64_cpu_capabilities *caps, u16 caps_type)

The "caps_type" argument should be named consistently with the
corresponding argument to update_cpu_capabilities().

[...]

quoted

quoted

 static void verify_local_cpu_errata_workarounds(void)
 {
-	if (__verify_local_cpu_caps(arm64_errata))
+	if (!__verify_local_cpu_caps(arm64_errata, ARM64_CPUCAP_TYPE_ALL))
 		cpu_die_early();

Did you mean to insert the ! here?

Thanks for spotting. I think it should have been there in the first place,
as we get "false" when there is a conflict. I will fix the previous patch which
adds the call.

Oh, right.  Yes, I think that probably makes sense.

Cheers
---Dave